CONEXANT CN8471AEPF Multichannel synchronous communications controller (musycc) Datasheet

Advance Information
This document contains information on a product under development. The parametric information
contains target parameters that are subject to change.
CN8478/CN8474A/CN8472A/CN8471A
Multichannel Synchronous Communications Controller (MUSYCC™)
Product Description
Distinguishing Features
The CN8478, CN8474A, CN8472A, and CN8471A are advanced Multichannel
Synchronous Communication Controllers (MUSYCCs) that format and deformat up
to 256 (CN8478), 128 (CN8474A), 64 (CN8472A), or 32 (CN8471A) HDLC
channels in a single CMOS integrated circuit. MUSYCC operates at Layer 2 of the
Open Systems Interconnection (OSI) protocol reference model. MUSYCC provides
a comprehensive, high-density solution for processing HDLC channels for
internetworking applications such as Frame Relay, ISDN D-channel signaling,
X.25, Signaling System 7 (SS7), DXI, ISUP, and LAN/WAN data transport. Under
minimal host supervision, MUSYCC manages a linked list of channel data buffers
in host memory by performing Direct Memory Access (DMA) of the HDLC
channels.
MUSYCC interfaces with eight independent serial data streams, such as T1/E1
signals, and then transfers data across the popular 32-bit Peripheral Component
Interface (PCI) bus to system memory at a rate of up to 66 MHz. Each serial
interface can be operated at up to 8.192 MHz. Logical channels can be mapped as
any combination of DS0 time slots to support ISDN hyperchannels (Nx64 kbps) or
as any number of bits in a DS0 for subchanneling applications (Nx8 kbps).
MUSYCC also includes a 32-bit expansion port for bridging the PCI bus to local
microprocessors or peripherals. A JTAG port enables boundary-scan testing to
replace bed-of-nails board testing.
Device drivers for Linux, VxWorks®, and pSOS™ operating systems are
available under a no-fee license agreement from Conexant. The device drivers
include C source code and supporting software documents.
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Functional Block Diagram
•
DMA
Controller
Tx/Rx-DMAC
Interrupt
Controller
Bit-Level
Processor
Tx/Rx-BLP
PCI Bus
PCI
Configuration
Space
(Function 0)
PCI
Configuration
Space
(Function 1)
•
Channel Group 1 – Serial Interface
Channel Group 2 – Serial Interface
PCI
Interface
Port
Interface
Tx/Rx
Channel Group 3 – Serial Interface
Channel Group 4 – Serial Interface
Serial Data Bus
Device
Configuration
Registers
Channel Group 0 – Serial Interface
Channel Group 5 – Serial Interface
Channel Group 6 – Serial Interface
Channel Group 7 – Serial Interface
Note: Number of serial interfaces is device-dependent.
Boundary Scan and Test Access
Expanion Bus Interface
Local Bus
Host
Interface
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Applications
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100660E
Conexant
256-, 128-, 64-, or 32-channel HDLC
controller
OSI Layer 2 protocol support
General purpose HDLC (ISO 3309)
– X.25 (LAPB)
– Frame relay (LAPF/ANSI T1.618)
– ISDN D-channel (LAPD/Q.921)
– SS7 support
8, 4, 2, or 1 independent serial interfaces
which support
– T1/E1 data streams
– DC to 8.192 Mbps TDM busses
Configurable logical channels
– Standard DS0 (56, 64 kbps)
– Hyperchannel (Nx64)
– Subchannel (Nx8)
Per-channel protocol mode selection
– 16-bit FCS mode
– 32-bit FCS mode
– SS7 mode (16-bit FCS)
– Transparent mode (unformatted data)
Per-channel DMA buffer management
– Linked list data structures
– Variable size transmit/receive FIFO
Per-channel message length check
– Select no length checking
– Select from two 12-bit registers to
compare message length
– Maximum length 16,384 Bytes
Direct PCI bus interface
– 32-bit, 66 or 33 MHz operation
– Bus master and slave operation
– PCI Version 2.1
Local Expansion Bus interface (EBUS)
– 32-bit multiplexed address/data bus
– Burst access up to 64 Bytes
Low power, 3.3/2.5 V CMOS operation
JTAG boundary scan access port
208-pin PQFP/surface-mount package
BGA
ISDN basic-rate or primary-rate interfaces
ISDN D-channel controller
Routers
Cellular base station switch controller
CSU/DSU
Protocol converter
Packet data switch
Frame relay switches/Frame Relay Access
Devices (FRAD)
DXI network interface
Distributed packet-based communications
system
Access multiplexer/concentrator
Ordering Information
Model Number
Version
Package
Temperature Range
CN8471AEPF
32-Channel
208-Pin Plastic Quad Flat Pack (PQFP)
–40 °C to +85 °C
CN8472AEPF
64-Channel
208-Pin Plastic Quad Flat Pack (PQFP)
–40 °C to +85 °C
CN8474AEPF
128-Channel
208-Pin Plastic Quad Flat Pack (PQFP)
–40 °C to +85 °C
CN8478EPF
256-Channel
208-Pin Plastic Quad Flat Pack (PQFP)
–40 °C to +85 °C
CN8471AEBG
32-Channel
208-Pin Plastic Ball Grid Array
–40 °C to +85 °C
CN8472AEBG
64-Channel
208-Pin Plastic Ball Grid Array
–40 °C to +85 °C
CN8474AEBG
128-Channel
208-Pin Plastic Ball Grid Array
–40 °C to +85 °C
CN8478EBG
256-Channel
208-Pin Plastic Ball Grid Array
–40 °C to +85 °C
© 2000, Conexant Systems, Inc.
All Rights Reserved.
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100660E
Conexant
Table of Contents
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
List of Tables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1.0
System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.1
2.0
Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
Host Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
2.1
PCI Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
2.1.1
2.1.2
2.1.3
2.2
PCI Configuration Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
3.0
PCI Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
PCI Bus Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
PCI Configuration Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Function 0 Network Controller—PCI Master and Slave. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Function 1 Expansion Bus Bridge, PCI Slave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
PCI Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
Host Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
PCI Bus Parity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
PCI Throughput and Latency Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
2.2.6.1
PCI Bus Latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-19
2.2.6.2
Latency Computation—Single Dword Access . . . . . . . . . . . . . . . . . . . . . . . . 2-21
2.2.6.3
Latency Computation—Burst Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Expansion Bus (EBUS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
3.1
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
3.1.1
3.1.2
3.1.3
3.1.4
3.1.5
3.1.6
3.1.7
3.1.8
3.1.9
3.1.10
3.1.11
100660E
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Address and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Address Duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Data Duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4
Bus Access Interval . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
PCI to EBUS Interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Microprocessor Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
Table of Contents
Multichannel Synchronous Communications Controller (MUSYCC™)
4.0
Serial Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
4.1
Serial Port Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.2
Bit Level Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.3
DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.4
Interrupt Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
4.5
Channelized Port Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
4.5.1
4.5.2
4.5.3
4.5.4
4.5.5
Serial Port Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
4.7
Tx and Rx FIFO Buffer Allocation and Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Example Channel BUFFLOC and BUFFLEN Specification . . . . . . . . . . . . . . . . . . . . . . . . . 4-13
Receiving Bit Stream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15
Transmitting Bit Stream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15
4.7.3.1
Transmit Data Bit Output Value Determination . . . . . . . . . . . . . . . . . . . . . . . 4-16
Memory Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1
Memory Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
5.1.1
5.1.2
5.2
Register Map Access and Shared Memory Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Memory Access Illustration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
5.2.1
5.2.2
5.2.3
5.2.4
iv
4-3
4-3
4-4
4-8
4-8
4.6
4.7.1
4.7.2
4.7.3
5.0
Hyperchannels (Nx64) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Subchannels (Nx8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Frame Synchronization Flywheel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Change-of-Frame Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Out-of-Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Host Interface Level Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
5.2.1.1
Global Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
5.2.1.2
Dual Address Cycle Base Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Channel Group Level Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
5.2.2.1
Group Base Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
5.2.2.2
Service Request . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
5.2.2.3
Group Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
5.2.2.4
Memory Protection Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
5.2.2.5
Port Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
5.2.2.6
Message Length Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
5.2.2.7
Time Slot Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
5.2.2.8
Subchannel Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Channel Level Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
5.2.3.1
Channel Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Message Level Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
5.2.4.1
Using Message Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
5.2.4.2
Note for Interrupt Driven Drivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
5.2.4.3
Head Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
5.2.4.4
Message Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
5.2.4.5
Message Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
5.2.4.6
Buffer Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
Table of Contents
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2.5
5.2.6
6.0
5.2.4.7
Buffer Status Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-34
5.2.4.8
Next Message Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
5.2.4.9
Data Buffer Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
5.2.4.10 Message Descriptor Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
Interrupt Level Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
5.2.5.1
Interrupt Queue Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
5.2.5.2
Interrupt Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-39
5.2.5.3
Interrupt Status Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-44
Interrupt Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45
5.2.6.1
Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45
5.2.6.2
Interrupt Descriptor Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-45
5.2.6.3
INTA* Signal Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-46
5.2.6.4
INTB* Signal Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-46
Basic Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1
Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
6.1.1
6.1.2
6.1.3
6.1.4
6.2
PCI Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Global Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Interrupt Queue Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Channel Group(s) Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Service Request Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
MUSYCC Internal Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.2.6.1
Memory Operations—Inactive Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
6.2.6.2
Memory Operations—Active Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Channel Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
6.3.1
6.3.2
6.3.3
6.3.4
6.3.5
6.3.6
6.3.7
6.3.8
6.3.9
6.3.10
6.3.11
6.3.12
6.3.13
6.3.14
6.3.15
100660E
6-1
6-2
6-3
6-3
Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
6.2.1
6.2.2
6.2.3
6.2.4
6.2.5
6.2.6
6.3
Hard PCI Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Soft Chip Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Soft Group Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Initialization Sequence Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Group Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Group Base Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10
Global Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Interrupt Queue Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Group Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Memory Protection Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Port Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Message Length Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Transmit Time Slot Map—Channel 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Transmit Subchannel Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Transmit Channel Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Receive Time Slot Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Receive Subchannel Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Receive Channel Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Message Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Conexant
Preliminary Information
v
CN8478/CN8474A/CN8472A/CN8471A
Table of Contents
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3.16
6.3.17
6.3.18
6.3.19
6.3.20
6.3.21
6.4
Protocol Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
6.4.1
6.4.2
6.4.3
6.4.4
6.4.5
6.4.6
6.4.7
6.4.8
6.4.9
6.4.10
6.5
vi
Frame Check Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
Opening/Closing Flags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
Abort Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-28
Zero-Bit Insertion/Deletion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
Message Configuration Bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
6.4.5.1
Idle Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
6.4.5.2
Inter-message Pad Fill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
6.4.5.3
Repeat Message Transmission. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
Message Configuration Bits Copy Enable/Disable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-29
Bit-Level Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31
6.4.7.1
Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-32
6.4.7.2
Receive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-32
HDLC Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
6.4.8.1
Transmit Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
6.4.8.2
Receive Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
6.4.8.3
Transmit Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-36
6.4.8.4
Receive Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37
Transparent Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43
6.4.9.1
Transmit Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
6.4.9.2
Receive Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
6.4.9.3
Transmit Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-45
6.4.9.4
Receive Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46
Intersystem Link Protocol (ISLP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Signaling System 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49
6.5.1
6.5.2
6.5.3
6.5.4
6.5.5
6.5.6
6.6
Channel Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-21
6.3.16.1 Transmit Channel Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-21
6.3.16.2 Receive Channel Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-22
Channel Deactivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
6.3.17.1 Transmit Channel Deactivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
6.3.17.2 Receive Channel Deactivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
Channel Jump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Frame Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Descriptor Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
Repeat Message Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-26
SS7 Repeat Message Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49
Message Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-49
Signal Unit Error Rate Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
SUERM Counter Incrementing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
SUERM Octet Counting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
SUERM Counter Decrementing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
Self-Servicing Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-51
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
Table of Contents
Multichannel Synchronous Communications Controller (MUSYCC™)
7.0
Electrical and Mechanical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1
Electrical and Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
7.1.1
7.1.2
7.1.3
7.2
Timing and Switching Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
7.2.1
7.2.2
7.2.3
7.2.4
7.2.5
7.2.6
7.2.7
8.0
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Host Interface (PCI) Timing and Switching Characteristic. . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Expansion Bus (EBUS) Timing and Switching Characteristic . . . . . . . . . . . . . . . . . . . . . 7-11
EBUS Arbitration Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14
Serial Interface Timing and Switching Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Package Thermal Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-18
Mechanical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
Terms, Definitions, and Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.1
Applicable Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
8.2
Numeric Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
8.3
Bit Stream Transmission Convention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
8.4
Bit Stream Storage Convention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
8.5
Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
8.6
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
8.7
Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Appendix A JTAG Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.1
Instruction Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.2
BYPASS Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
100660E
Conexant
Preliminary Information
vii
CN8478/CN8474A/CN8472A/CN8471A
Table of Contents
Multichannel Synchronous Communications Controller (MUSYCC™)
viii
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
List of Figures
Multichannel Synchronous Communications Controller (MUSYCC™)
List of Figures
Figure 1-1.
Figure 1-2.
Figure 1-3.
Figure 1-4.
Figure 1-5.
Figure 1-6.
Figure 1-7.
Figure 1-8.
Figure 1-9.
Figure 1-10.
Figure 1-11.
Figure 1-12.
Figure 2-1.
Figure 2-2.
Figure 3-1.
Figure 3-2.
Figure 3-3.
Figure 3-4.
Figure 3-5.
Figure 3-6.
Figure 4-1.
Figure 4-2.
Figure 4-3.
Figure 4-4.
Figure 4-5.
Figure 4-6.
Figure 4-7.
Figure 4-8.
Figure 5-1.
Figure 5-2.
Figure 7-1.
Figure 7-2.
Figure 7-3.
Figure 7-4.
Figure 7-5.
Figure 7-6.
Figure 7-7.
Figure 7-8.
Figure 7-9.
100660E
System Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Detailed System Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
MUSYCC Application Example—Frame Relay Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
CN8478 MQFP Pinout Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5
CN8474A MPQF Pinout Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
CN8472A MQFP Pinout Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
CN8471A MQFP Pinout Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
CN8478 PBGA Pinout Configuration (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
CN8474A PBGA Pinout Configuration (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
CN8472A PBGA Pinout Configuration (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
CN8471A PBGA Pinout Configuration (Top View) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
CN8478 Logic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17
Host Interface Functional Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Address Lines During Configuration Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
EBUS Functional Block Diagram with Local MPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
EBUS Functional Block Diagram without Local MPU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
EBUS Address/Data Line Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
EBUS Connection, Non-multiplexed Address/Data, 8 Framers, No MPU . . . . . . . . . . . . . . . 3-8
EBUS Connection, Non-multiplexed Address/Data, 61 Framers, No MPU . . . . . . . . . . . . . . 3-9
EBUS Connection, Multiplexed Address/Data, 8 Framers, No MPU. . . . . . . . . . . . . . . . . . 3-10
Serial Interface Functional Block Diagram, Channel Group 0. . . . . . . . . . . . . . . . . . . . . . . . 4-1
Transmit and Receive T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
Transmit and Receive E1 (also 2xE1, 4xE1) Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Transmit and Receive Nx64 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Serial Port Mapping Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Receive Data Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Transmit Data Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12
Transmit Data Bit Output Value Determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16
Shared Memory Model Per Channel Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Interrupt Notification To Host . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-47
PCI Clock (PCLK) Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
PCI Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
PCI Output Timing Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
PCI Input Timing Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
PCI Read Multiple Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
PCI Write Multiple Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
PCI Write Single Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
ECLK to PCLK Relationship (M66EN = 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
ECLK to PCKL Relationship (M66EN = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Conexant
ix
CN8478/CN8474A/CN8472A/CN8471A
List of Figures
Multichannel Synchronous Communications Controller (MUSYCC™)
Figure 7-10.
Figure 7-11.
Figure 7-12.
Figure 7-13.
Figure 7-14.
Figure 7-15.
Figure 7-16.
Figure 7-17.
Figure 7-18.
Figure 7-19.
Figure 7-20.
Figure A-1.
x
EBUS Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
EBUS Output Timing Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
EBUS Input Timing Waveform. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
EBUS Write/Read Transactions, Intel-Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-14
EBUS Write/Read Transactions, Motorola-Style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15
Serial Interface Clock (RCLK,TCLK) Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Serial Interface Clock (RCLK,TCLK) Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-17
Serial Interface Data Input Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-17
Serial Interface Data Delay Output Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-18
208-Pin Metric Quad Flatpack (MQFP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-19
208-Pin Plastic Ball Grid Array (PBGA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-20
JTAG Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
List of Tables
Multichannel Synchronous Communications Controller (MUSYCC™)
List of Tables
Table 1-1.
Table 1-2.
Table 1-3.
Table 1-4.
Table 2-1.
Table 2-2.
Table 2-3.
Table 2-4.
Table 2-5.
Table 2-6.
Table 2-7.
Table 2-8.
Table 2-9.
Table 2-10.
Table 2-11.
Table 2-12.
Table 2-13.
Table 2-14.
Table 2-15.
Table 2-16.
Table 2-17.
Table 3-1.
Table 3-2.
Table 4-1.
Table 4-2.
Table 4-3.
Table 4-4.
Table 4-5.
Table 5-1.
Table 5-2.
Table 5-3.
Table 5-4.
Table 5-5.
Table 5-6.
Table 5-7.
Table 5-8.
Table 5-9.
Table 5-10.
Table 5-11.
100660E
CN8478 MQFP Pin List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
CN8478 PBGA Pin List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12
I/O Pin Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18
CN8478 Hardware Signal Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
Function 0 Configuration Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Function 1 Configuration Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Register 0, Address 00h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
Register 1, Address 04h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Register 2, Address 08h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Register 3, Address 0Ch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Register 4, Address 10h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Registers 5–14, Addresses 14h–38h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12
Register 15, Address 3Ch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Register 0, Address 00h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Register 1, Address 04h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Register 2, Address 08h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Register 3, Address 0Ch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Register 4, Address 10h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Registers 5 through 14–Addresses 14h through 38h . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-16
Register 15, Address 3Ch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
PCI Latency Example. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
Intel Protocol Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Motorola Protocol Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Channelized Serial Port Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Internal Buffer Memory Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Example of 32-Channel with Subchanneling Buffer Allocation (Receive or Transmit) . . . . . 4-13
Example of 32-Channel without Subchanneling Buffer Allocation (Receive or Transmit) . . 4-14
Example of 16-Channel without Subchanneling Buffer Allocation (Receive or Transmit) . . 4-14
MUSYCC Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Group Structure Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
MUSYCC PCI Function Memory Allocation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Shared Memory Allocation—Group Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Host Assigns Group Base Pointers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Global Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10
Dual Address Cycle Base Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Group Base Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Service Request Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-14
Group Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Memory Protection Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-18
Conexant
xi
CN8478/CN8474A/CN8472A/CN8471A
List of Tables
Multichannel Synchronous Communications Controller (MUSYCC™)
Table 5-12.
Table 5-13.
Table 5-14.
Table 5-15.
Table 5-16.
Table 5-17.
Table 5-18.
Table 5-19.
Table 5-20.
Table 5-21.
Table 5-22.
Table 5-23.
Table 5-24.
Table 5-25.
Table 5-26.
Table 5-27.
Table 5-28.
Table 5-29.
Table 5-30.
Table 5-31.
Table 5-32.
Table 6-1.
Table 6-2.
Table 6-3.
Table 6-4.
Table 6-5.
Table 6-6.
Table 6-7.
Table 6-8.
Table 6-9.
Table 6-10.
Table 6-11.
Table 6-12.
Table 6-13.
Table 7-1.
Table 7-2.
Table 7-3.
Table 7-4.
Table 7-5.
Table 7-6.
Table 7-7.
Table 7-8.
Table 7-9.
Table 7-10.
Table 7-11.
Table 7-12.
xii
Port Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-19
Message Length Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20
Transmit or Receive Time Slot Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-22
Time Slot Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Transmit or Receive Subchannel Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Subchannel Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Channel Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Message Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
Head Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
Message Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
Transmit Buffer Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-33
Receive Buffer Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-34
Transmit Buffer Status Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-35
Receive Buffer Status Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-36
Next Descriptor Pointer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
Data Buffer Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-37
Interrupt Queue Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
Interrupt Queue Pointer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
Interrupt Queue Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-38
Interrupt Descriptor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-41
Interrupt Status Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-44
Example—Components of Group Base Pointer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10
Example—Components of Global Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Example—Components of Interrupt Queue Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Example—Components of Group Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Example—Components of Memory Protection Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Example—Components of Port Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Example—Components of Message Length Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Example—Components of Transmit Time Slot Map – Channel 0 . . . . . . . . . . . . . . . . . . . . 6-16
Example—Components of Transmit Subchannel Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-17
Example—Components of Channel Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . 6-18
Polling Frequency Using a Time Slot Counter Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-26
Memory Map for Message Configuration Descriptor Table . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
Message Configuration Descriptor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Electrical Operating Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
PCI Interface DC Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
PCI Clock (PCLK) Waveform Parameters, 33 MHz PCI Clock . . . . . . . . . . . . . . . . . . . . . . . . 7-4
PCI Clock (PCLK) Waveform Parameters, 66 MHz PCI Clock . . . . . . . . . . . . . . . . . . . . . . . . 7-5
PCI Reset Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
PCI I/O Timing Parameters, 33 MHz PCI Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
PCI I/O Timing Parameters, 66 MHz PCI Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
PCI I/O Measure Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
EBUS Reset Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
EBUS I/O Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
List of Tables
Multichannel Synchronous Communications Controller (MUSYCC™)
Table 7-13.
Table 7-14.
Table 7-15.
Table 7-16.
Table 7-17.
Table 7-18.
Table 8-1.
Table 8-2.
Table 8-3.
Table 8-4.
Table 8-5.
Table 8-6.
Table 8-7.
Table A-1.
Table A-2.
100660E
EBUS I/O Measure Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Serial Interface Clock (RCLK, TCLK) Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Serial Interface I/O Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Serial Interface Clock Hysteresis (RCLK, TCLK, with Schmitt Trigger) . . . . . . . . . . . . . . . . 7-16
Serial Interface I/O Measure Conditions for 3.3 V Signaling . . . . . . . . . . . . . . . . . . . . . . . . 7-17
MUSYCC Package Thermal Resistance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-18
Number Representation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Digitized Voice Transmission Convention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Digital Data Transmission Convention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
MUSYCC Byte Transmission Convention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Little-Endian Storage Convention (Intel-style). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Big-Endian Storage Convention (Motorola-style) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
CN8478 Data Sheet Revisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
IEEE Std. 1149.1 Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
JTAG Timing Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Conexant
xiii
CN8478/CN8474A/CN8472A/CN8471A
List of Tables
Multichannel Synchronous Communications Controller (MUSYCC™)
xiv
Conexant
100660E
1
1.0 System Description
The Conexant MUSYCC is a high-throughput communications controller for synchronous, link-layer
applications that multiplexes and demultiplexes up to 256 data channels. Each channel can be configured to
support HDLC, Transparent, or SS7 applications. MUSYCC operates at the Layer 2 (the data link protocol
level) reference of the International Organization for Standardization (ISO) Open Systems Interconnection
(OSI). MUSYCC is installed between the multiple serial interface devices and the shared buffer memory of one
or more host processors.
MUSYCC’s serial ports interface to a standard Pulse Code Modulation (PCM) highway, which operates at
T1, E1, 2xE1, or 4xE1 rates. Data can be formatted in the HDLC protocol or left unformatted. The protocol is
specified on a per-channel and direction basis.
An on-device Peripheral Components Interface (PCI) controller, known as the host interface, is provided.
Access to MUSYCC is available through PCI read, write, and configuration cycles (see Figure 1-1).
Host
Interface
(PCI)
System
Memory
Optional
Components
Expansion
Bus
Interface
Local
Host
Serial
Interface 2
Physical
Interface 1
Physical
Interface 2
Serial
Interface 3
Physical
Interface 3
Serial
Interface 4
Physical
Interface 4
Serial
Interface 5
Serial
Interface 6
Local
Memory
PCM Highway(s)
JTAG
Serial
Interface 1
Local
Bus
PCI
Bridge
Physical
Interface 0
Serial
Interface 0
Serial
Interface 7
MUSYCC
EBUS
PCM Highway(s)
PCI Bus
System
Host
Local Bus
Figure 1-1. System Block Diagram
Physical
Interface 5
Physical
Interface 6
Physical
Interface 7
8478_001
100660E
Conexant
1-1
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
MUSYCC also provides an on-device, 32-bit local expansion bus (EBUS) controller which allows a host
processor to access local memory and physical interface devices directly through MUSYCC over the PCI using
configurable memory mapping features.
MUSYCC manages buffer memory for each active data channel with common list-processing structures.
The on-device features allow data transmission between buffer memory and the serial interfaces with minimum
host processor intervention. This allows the host processor to concentrate on managing the higher layers of the
protocol stack.
Figures 1-2 and 1-3 illustrate detailed system block diagrams and a sample application.
1-2
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
Figure 1-2. Detailed System Block Diagram
PERR*
IDSEL*
FRAME*
IRDY*
TRDY*
DEVSEL*
STOP*
PAR*
CBE[3:0]*
AD[31:0]
Bit-Level
Processor
Tx/Rx-BLP
Port
Interface
Tx/Rx
Serial Interface Channel Group 1
PCI
Interface
PCI
Configuration
Space
[Function 0]
PCI
Configuration
Space
[Function 1]
M66EN
PCI Bus
3.3/5.0 Volt, 33/66 MHz
DMA
Controller
Tx/Rx-DMAC
Interrupt
Controller
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Port
Interface
Tx/Rx
Port
Interface
Tx/Rx
RCLK2
RSYNC2
RDAT2
ROOF2
TCLK2
TSYNC2
TDAT2
Port
Interface
Tx/Rx
RCLK3
RSYNC3
RDAT3
ROOF3
TCLK3
TSYNC3
TDAT3
Serial Interface Channel Group 2
Interrupt
Controller
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Serial Interface Channel Group 3
Interrupt
Controller
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Serial Interface Channel Group 4
Interrupt
Controller
TCK
TEN*
TMS
TDO
TDI
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Port
Interface
Tx/Rx
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Port
Interface
Tx/Rx
Port
Interface
Tx/Rx
RCLK6
RSYNC6
RDAT6
ROOF6
TCLK6
TSYNC6
TDAT6
Port
Interface
Tx/Rx
RCLK7
RSYNC7
RDAT7
ROOF7
TCLK7
TSYNC7
TDAT7
Serial Interface Channel Group 6
Interrupt
Controller
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Serial Interface Channel Group 7
Interrupt
Controller
Scan
DMA
Controller
Tx/Rx-DMAC
Bit-Level
Processor
Tx/Rx-BLP
Boundary Scan and Test Access
Data
Expansion Bus Interface
Control
RCLK4
RSYNC4
RDAT4
ROOF4
TCLK4
TSYNC4
TDAT4
RCLK5
RSYNC5
RDAT5
ROOF5
TCLK5
TSYNC5
TDAT5
Serial Interface Channel Group 5
Interrupt
Controller
RCLK1
RSYNC1
RDAT1
ROOF1
TCLK1
TSYNC1
TDAT1
Serial Interface System Bus
INTA*
GNT*
REQ*
SERR*
Device
Configuration
Registers
Interrupt
Controller
RCLK0
RSYNC0
RDAT0
ROOF0
TCLK0
TSYNC0
TDAT0
Serial Interface System Bus
PCLK
PRST*
INTB*
Serial Interface Channel Group 0
SCAN_EN
TM0
TM1
ECLK
RD* (DS*)
WR* (R/WR*)
ALE*
BGACK*
HOLD (BR*)
HLDA (BG*)
EBE[3:0]*
EAD[31:0]*
EINT*
Microprocessor
Bus
Host Interface
8478_002
100660E
Conexant
1-3
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
Figure 1-3. MUSYCC Application Example—Frame Relay Switch
Frame Relay Network
Control
Data
PHY
PHY
PHY
PHY
PHY
System Bus – PCM Highway
Tx
Clk, Data,
Sync
PHY
PHY
PHY
System Bus – PCM Highway
Rx
Clk, Data,
Sync, OOF
Physical Layer
Tx
Clk, Data,
Sync
Rx
Clk, Data,
Sync, OOF
Data Link Layer
Port 0
Port 1
Ch Grp 0 Ch Grp 1
MPU
(Optional)
Port 2
Port 3
Port 4
Port 5
Ch Grp 2
Ch Grp 3
Ch Grp 4
Ch Grp 5
Serial Port Interface
Port 6
Port 7
Ch Grp 6 Ch Grp 7
EBUS
Interface
CN8478
32-Bit
Address
and Data
Multiplexed
EBUS
Host Interface (PCI)
PCI Bus
PCI Local Bus Bridge
System Host
Channel Group 7 Descriptor
Channel Group 6 Descriptor
Channel Group 5 Descriptor
Channel Group 4 Descriptor
Channel Group 3 Descriptor
Channel Group 2 Descriptor
Configuration
Channel Group 1 Descriptor
Channel Group 0 Descriptor
Tx Channel 31 Message List
Tx Channel ... Message List
Interrupt
Queue
Tx Channel 0 Message List
Rx Channel 31 Message List
Rx Channel ... Message List
Rx Channel 0 Message List
8478_003
1-4
System Memory
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
1.1 Pin Descriptions
Figures 1-4 through 1-7 illustrate the pinouts for CN8478, CN8474A, CN8472A, and CN8471A. Signals
marked with black are NCs. Tables 1-1 and 1-2 summarize the pin assignments for the CN8478 in the MQFP
and PBGA packages, respectively. Table 1-3 lists the pin input and output functions. Table 1-4 lists the hardware
signal definitions.
208
207
206
205
204
203
202
201
200
199
198
197
196
195
194
193
192
191
190
189
188
187
186
185
184
183
182
181
180
179
178
177
176
175
174
173
172
171
170
169
168
167
166
165
164
163
162
161
160
159
158
157
RCLK[7]
ROOF[7]
NC
NC
EBE[0]*
EBE[1]*
VSSo
VDDo
EBE[2]*
EBE[3]*
BGACK*
HLDA(BG*)
HOLD(BR*)
EINT*
ALE*(AS*)
RD*(DS*)
R*(R/WR*)
VSSo
ECLK
EAD[31]
EAD[30]
EAD[29]
VSS
VDDc
EAD[28]
EAD[27]
VSSo
VDDo
EAD[26]
EAD[25]
EAD[24]
EAD[23]
EAD[22]
VSSo
EAD[21]
EAD[20]
VSS
VDDp
EAD[19]
EAD[18]
EAD[17]
EAD[16]
EAD[15]
VSSo
VDDo
EAD[14]
EAD[13]
EAD[12]
EAD[11]
EAD[10]
EAD[9]
VSS
Figure 1-4. CN8478 MQFP Pinout Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Preliminary
CN8478
156
155
154
153
152
151
150
149
148
147
146
145
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
108
107
106
105
VGG
EAD[8]
EAD[7]
VSSo
EAD[6]
EAD[5]
EAD[4]
EAD[3]
VSSo
VDDo
EAD[2]
EAD[1]
EAD[0]
TCLK[3]
TSYNC[3]
TDAT[3]
TCLK[7]
TSYNC[7]
TDAT[7]
VSSo
TCLK[2]
TSYNC[2]
TDAT[2]
VSS
VDDc
TCLK[6]
TSYNC[6]
TDAT[6]
TCLK[1]
TSYNC[1]
TDAT[1]
TCLK[5]
TSYNC[5]
TDAT[5]
TCLK[0]
TSYNC[0]
TDAT[0]
VSS
VDDp
TCLK[4]
TSYNC[4]
TDAT[4]
TM[0]
TM[1]
TM[2]
VSSo
VDDo
AD[0]
AD[1]
AD[2]
AD[3]
AD[4]
VSS
AD[27]
VSSo
AD[26]
AD[25]
AD[24]
CBE[3]*
IDSEL
AD[23]
AD[22]
VDDo
VSSo
AD[21]
AD[20]
VDDp
VSS
AD[19]
AD[18]
AD[17]
AD[16]
VSSo
CBE[2]*
FRAME*
IRDY*
VDDc
VSS
TRDY*
DEVSEL*
VDDo
VSSo
STOP*
PERR*
SERR*
PAR
CBE[1]*
AD[15]
VSSo
AD[14]
AD[13]
AD[12]
AD[11]
AD[10]
VDDo
VSSo
AD[9]
M66EN
AD[8]
CBE[0]*
AD[7]
AD[6]
AD[5]
VSSo
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
RSYNC[7]
RDAT[7]
ROOF[3]
RCLK[3]
RSYNC[3]
RDAT[3]
ROOF[6]
RCLK[6]
RSYNC[6]
RDAT[6]
ROOF[2]
RCLK[2]
VDDp
VSS
RSYNC[2]
RDAT[2]
ROOF[5]
RCLK[5]
RSYNC[5]
RDAT[5]
ROOF[1]
RCLK[1]
RSYNC[1]
RDAT[1]
ROOF[4]
RCLK[4]
VDDc
VSS
RSYNC[4]
RDAT[4]
ROOF[0]
RCLK[0]
RSYNC[0]
RDAT[0]
TCK
TRST*
TMS
TDO
TDI
INTB*
INTA*
VDDo
PCLK
VSSo
PRST
GNT*
REQ*
AD[31]
AD[30]
AD[29]
AD[28]
VGG
100660E
Conexant
1-5
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-1. CN8478 MQFP Pin List
Pin
Number
Pin Label
Pin
Number
Pin Label
Pin
Number
Pin Label
1
RSYNC[7]
36
TRST*
71
AD[17]
2
RDAT[7]
37
TMS
72
AD[16]
3
ROOF[3]
38
TDO
73
VSSo
4
RCLK[3]
39
TDI
74
CBE[2]*
5
RSYNC[3]
40
INTB*
75
FRAME*
6
RDAT[3]
41
INTA*
76
IRDY*
7
ROOF[6]
42
VDDo
77
VDDc
8
RCLK[6]
43
PCLK
78
VSS
9
RSYNC[6]
44
VSSo
79
TRDY*
10
RDAT[6]
45
PRST*
80
DEVSEL*
11
ROOF[2]
46
GNT*
81
VDDo
12
RCLK[2]
47
REQ*
82
VSSo
13
VDDi
48
AD[31]
83
STOP*
14
VSS
49
AD[30]
84
PERR*
15
RSYNC[2]
50
AD[29]
85
SERR*
16
RDAT[2]
51
AD[28]
86
PAR
17
ROOF[5]
52
VGG
87
CBE[1]
18
RCLK[5]
53
VSS
88
AD[15]
19
RSYNC[5]
54
AD[27]
89
VSSo
20
RDAT[5]
55
VSSo
90
AD[14]
21
ROOF[1]
56
AD[26]
91
AD[13]
22
RCLK[1]
57
AD[25]
92
AD[12]
23
RSYNC[1]
58
AD[24]
93
AD[11]
24
RDAT[1]
59
CBE[3]*
94
AD[10]
25
ROOF[4]
60
IDSEL
95
VDDo
26
RCLK[4]
61
AD[23]
96
VSSo
27
VDDc
62
AD[22]
97
AD[9]
28
VSS
63
VDDo
98
M66EN
29
RSYNC[4]
64
VSSo
99
AD[8]
30
RDAT[4]
65
AD[21]
100
CBE[0]*
31
ROOF[0]
66
AD[20]
101
AD[7]
32
RCLK[0]
67
VDDi
102
AD[6]
33
RSYNC[0]
68
VSS
103
AD[5]
34
RDAT[0]
69
AD[19]
104
VSSo
35
TCK
70
AD[18]
105
AD[4]
1-6
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
Pin
Number
Pin Label
Pin
Number
Pin Label
1.1 Pin Descriptions
Pin
Number
Pin Label
106
AD[3]
142
TSYNC[3]
178
EAD[24]
107
AD[2]
143
TCLK[3]
179
EAD[25]
108
AD[1]
144
EAD[0]
180
EAD[26]
109
AD[0]
145
EAD[1]
181
VDDo
110
VDDo
146
EAD[2]
182
VSSo
111
VSSo
147
VDDo
183
EAD[27]
112
TM[2]
148
VSSo
184
EAD[28]
113
TM[1]
149
EAD[3]
185
VDDc
114
TM[0]
150
EAD[4]
186
VSS
115
TDAT[4]
151
EAD[5]
187
EAD[29]
116
TSYNC[4]
152
EAD[6]
188
EAD[30]
117
TCLK[4]
153
VSSo
189
EAD[31]
118
VDDi
154
EAD[7]
190
ECLK
119
VSS
155
EAD[8]
191
VSSo
120
TDAT[0]
156
VGG
192
WR*(R/ WR*)
121
TSYNC[0]
157
VSS
193
RD*(DS*)
122
TCLK[0]
158
EAD[9]
194
ALE*(AS*)
123
TDAT[5]
159
EAD[10]
195
EINT*
124
TSYNC[5]
160
EAD[11]
196
HOLD(BR*)
125
TCLK[5]
161
EAD[12]
197
HLDA(BG*)
126
TDAT[1]
162
EAD[13]
198
BGACK*
127
TSYNC[1]
163
EAD[14]
199
EBE[3]*
128
TCLK[1]
164
VDDo
200
EBE[2]*
129
TDAT[6]
165
VSSo
201
VDDo
130
TSYNC[6]
166
EAD[15]
202
VSSo
131
TCLK[6]
167
EAD[16]
203
EBE[1]*
132
VDDc
168
EAD[17]
204
EBE[0]*
133
VSS
169
EAD[18]
205
NC
134
TDAT[2]
170
EAD[19]
206
NC
135
TSYNC[2]
171
VDDi
207
ROOF[7]
136
TCLK[2]
172
VSS
208
RCLK[7]
137
VSSo
173
EAD[20]
138
TDAT[7]
174
EAD[21]
139
TSYNC[7]
175
VSSo
140
TCLK[7]
176
EAD[22]
141
TDAT[3]
177
EAD[23]
100660E
Conexant
1-7
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
1.1 Pin Descriptions
Multichannel Synchronous Communications Controller (MUSYCC™)
208
207
206
205
204
203
202
201
200
199
198
197
196
195
194
193
192
191
190
189
188
187
186
185
184
183
182
181
180
179
178
177
176
175
174
173
172
171
170
169
168
167
166
165
164
163
162
161
160
159
158
157
NC
NC
NC
NC
EBE[0]*
EBE[1]*
VSSo
VDDo
EBE[2]*
EBE[3]*
BGACK*
HLDA(BG*)
HOLD(BR*)
EINT*
ALE*(AS*)
RD*(DS*)
R*(R/WR*)
VSSo
ECLK
EAD[31]
EAD[30]
EAD[29]
VSS
VDDc
EAD[28]
EAD[27]
VSSo
VDDo
EAD[26]
EAD[25]
EAD[24]
EAD[23]
EAD[22]
VSSo
EAD[21]
EAD[20]
VSS
VDDp
EAD[19]
EAD[18]
EAD[17]
EAD[16]
EAD[15]
VSSo
VDDo
EAD[14]
EAD[13]
EAD[12]
EAD[11]
EAD[10]
EAD[9]
VSS
Figure 1-5. CN8474A MPQF Pinout Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Preliminary
CN8474A
156
155
154
153
152
151
150
149
148
147
146
145
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
108
107
106
105
VGG
EAD[8]
EAD[7]
VSSo
EAD[6]
EAD[5]
EAD[4]
EAD[3]
VSSo
VDDo
EAD[2]
EAD[1]
EAD[0]
TCLK[3]
TSYNC[3]
TDAT[3]
NC
NC
NC
VSSo
TCLK[2]
TSYNC[2]
TDAT[2]
VSS
VDDc
NC
NC
NC
TCLK[1]
TSYNC[1]
TDAT[1]
NC
NC
NC
TCLK[0]
TSYNC[0]
TDAT[0]
VSS
VDDp
NC
NC
NC
TM[0]
TM[1]
TM[2]
VSSo
VDDo
AD[0]
AD[1]
AD[2]
AD[3]
AD[4]
VSS
AD[27]
VSSo
AD[26]
AD[25]
AD[24]
CBE[3]*
IDSEL
AD[23]
AD[22]
VDDo
VSSo
AD[21]
AD[20]
VDDp
VSS
AD[19]
AD[18]
AD[17]
AD[16]
VSSo
CBE[2]*
FRAME*
IRDY*
VDDc
VSS
TRDY*
DEVSEL*
VDDo
VSSo
STOP*
PERR*
SERR*
PAR
CBE[1]*
AD[15]
VSSo
AD[14]
AD[13]
AD[12]
AD[11]
AD[10]
VDDo
VSSo
AD[9]
M66EN
AD[8]
CBE[0]*
AD[7]
AD[6]
AD[5]
VSSo
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
NC
NC
ROOF[3]
RCLK[3]
RSYNC[3]
RDAT[3]
NC
NC
NC
NC
ROOF[2]
RCLK[2]
VDDp
VSS
RSYNC[2]
RDAT[2]
NC
NC
NC
NC
ROOF[1]
RCLK[1]
RSYNC[1]
RDAT[1]
NC
NC
VDDc
VSS
NC
NC
ROOF[0]
RCLK[0]
RSYNC[0]
RDAT[0]
TCK
TRST*
TMS
TDO
TDI
INTB*
INTA*
VDDo
PCLK
VSSo
PRST
GNT*
REQ*
AD[31]
AD[30]
AD[29]
AD[28]
VGG
NOTE(S): An active low signal is denoted by a trailing asterisk (*).
1-8
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
208
207
206
205
204
203
202
201
200
199
198
197
196
195
194
193
192
191
190
189
188
187
186
185
184
183
182
181
180
179
178
177
176
175
174
173
172
171
170
169
168
167
166
165
164
163
162
161
160
159
158
157
NC
NC
NC
NC
EBE[0]*
EBE[1]*
VSSo
VDDo
EBE[2]*
EBE[3]*
BGACK*
HLDA(BG*)
HOLD(BR*)
EINT*
ALE*(AS*)
RD*(DS*)
R*(R/WR*)
VSSo
ECLK
EAD[31]
EAD[30]
EAD[29]
VSS
VDDc
EAD[28]
EAD[27]
VSSo
VDDo
EAD[26]
EAD[25]
EAD[24]
EAD[23]
EAD[22]
VSSo
EAD[21]
EAD[20]
VSS
VDDp
EAD[19]
EAD[18]
EAD[17]
EAD[16]
EAD[15]
VSSo
VDDo
EAD[14]
EAD[13]
EAD[12]
EAD[11]
EAD[10]
EAD[9]
VSS
Figure 1-6. CN8472A MQFP Pinout Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Preliminary
CN8472A
156
155
154
153
152
151
150
149
148
147
146
145
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
108
107
106
105
VGG
EAD[8]
EAD[7]
VSSo
EAD[6]
EAD[5]
EAD[4]
EAD[3]
VSSo
VDDo
EAD[2]
EAD[1]
EAD[0]
NC
NC
NC
NC
NC
NC
VSSo
NC
NC
NC
VSS
VDDc
NC
NC
NC
TCLK[1]
TSYNC[1]
TDAT[1]
NC
NC
NC
TCLK[0]
TSYNC[0]
TDAT[0]
VSS
VDDp
NC
NC
NC
TM[0]
TM[1]
TM[2]
VSSo
VDDo
AD[0]
AD[1]
AD[2]
AD[3]
AD[4]
VSS
AD[27]
VSSo
AD[26]
AD[25]
AD[24]
CBE[3]*
IDSEL
AD[23]
AD[22]
VDDo
VSSo
AD[21]
AD[20]
VDDp
VSS
AD[19]
AD[18]
AD[17]
AD[16]
VSSo
CBE[2]*
FRAME*
IRDY*
VDDc
VSS
TRDY*
DEVSEL*
VDDo
VSSo
STOP*
PERR*
SERR*
PAR
CBE[1]*
AD[15]
VSSo
AD[14]
AD[13]
AD[12]
AD[11]
AD[10]
VDDo
VSSo
AD[9]
M66EN
AD[8]
CBE[0]*
AD[7]
AD[6]
AD[5]
VSSo
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
VDDp
VSS
NC
NC
NC
NC
NC
NC
ROOF[1]
RCLK[1]
RSYNC[1]
RDAT[1]
NC
NC
VDDc
VSS
NC
NC
ROOF[0]
RCLK[0]
RSYNC[0]
RDAT[0]
TCK
TRST*
TMS
TDO
TDI
INTB*
INTA*
VDDo
PCLK
VSSo
PRST
GNT*
REQ*
AD[31]
AD[30]
AD[29]
AD[28]
VGG
NOTE(S): An active low signal is denoted by a trailing asterisk (*).
100660E
Conexant
1-9
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
1.1 Pin Descriptions
Multichannel Synchronous Communications Controller (MUSYCC™)
208
207
206
205
204
203
202
201
200
199
198
197
196
195
194
193
192
191
190
189
188
187
186
185
184
183
182
181
180
179
178
177
176
175
174
173
172
171
170
169
168
167
166
165
164
163
162
161
160
159
158
157
NC
NC
NC
NC
EBE[0]*
EBE[1]*
VSSo
VDDo
EBE[2]*
EBE[3]*
BGACK*
HLDA(BG*)
HOLD(BR*)
EINT*
ALE*(AS*)
RD*(DS*)
R*(R/WR*)
VSSo
ECLK
EAD[31]
EAD[30]
EAD[29]
VSS
VDDc
EAD[28]
EAD[27]
VSSo
VDDo
EAD[26]
EAD[25]
EAD[24]
EAD[23]
EAD[22]
VSSo
EAD[21]
EAD[20]
VSS
VDDp
EAD[19]
EAD[18]
EAD[17]
EAD[16]
EAD[15]
VSSo
VDDo
EAD[14]
EAD[13]
EAD[12]
EAD[11]
EAD[10]
EAD[9]
VSS
Figure 1-7. CN8471A MQFP Pinout Configuration
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Preliminary
CN8471A
156
155
154
153
152
151
150
149
148
147
146
145
144
143
142
141
140
139
138
137
136
135
134
133
132
131
130
129
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
108
107
106
105
VGG
EAD[8]
EAD[7]
VSSo
EAD[6]
EAD[5]
EAD[4]
EAD[3]
VSSo
VDDo
EAD[2]
EAD[1]
EAD[0]
NC
NC
NC
NC
NC
NC
VSSo
NC
NC
NC
VSS
VDDc
NC
NC
NC
NC
NC
NC
NC
NC
NC
TCLK[0]
TSYNC[0]
TDAT[0]
VSS
VDDp
NC
NC
NC
TM[0]
TM[1]
TM[2]
VSSo
VDDo
AD[0]
AD[1]
AD[2]
AD[3]
AD[4]
VSS
AD[27]
VSSo
AD[26]
AD[25]
AD[24]
CBE[3]*
IDSEL
AD[23]
AD[22]
VDDo
VSSo
AD[21]
AD[20]
VDDp
VSS
AD[19]
AD[18]
AD[17]
AD[16]
VSSo
CBE[2]*
FRAME*
IRDY*
VDDc
VSS
TRDY*
DEVSEL*
VDDo
VSSo
STOP*
PERR*
SERR*
PAR
CBE[1]*
AD[15]
VSSo
AD[14]
AD[13]
AD[12]
AD[11]
AD[10]
VDDo
VSSo
AD[9]
M66EN
AD[8]
CBE[0]*
AD[7]
AD[6]
AD[5]
VSSo
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
VDDp
VSS
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
VDDc
VSS
NC
NC
ROOF[0]
RCLK[0]
RSYNC[0]
RDAT[0]
TCK
TRST*
TMS
TDO
TDI
INTB*
INTA*
VDDo
PCLK
VSSo
PRST
GNT*
REQ*
AD[31]
AD[30]
AD[29]
AD[28]
VGG
NOTE(S): An active low signal is denoted by a trailing asterisk(*).
1-10
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Figure 1-8. CN8478 PBGA Pinout Configuration (Top View)
2
1
VSSo
A
B
3
D
E
F
G
H
J
K
L
ROOF[3]
EBE[0]*
ECLK
9
10
EAD[27]
11
12
13
EAD[20]
14
EAD[16]
15
16
EAD[10]
WR*(R/WR*)
EAD[28]
EAD[21]
EAD[14]
EAD[9]
VGG
EBE[3]*
ALE*(AS*)
EAD[26]
EAD[19]
EAD[6]
EAD[7]
VDDo
EAD[31]
EAD[15]
VDDo
VSS
RCLK[5]
RSYNC[5]
RSYNC[1]
ROOF[1]
VSS
RCLK[1]
VDDc
ROOF[4]
RDAT[1]
VSS
RCLK[4]
ROOF[0]
RCLK[0]
RSYNC[4]
VSS
VSS
VSS
VDDc
VSS
VSS
VSS
TDAT[1]
TDAT[6]
TCLK[5]
TDAT[5]
VSS
VDDi
TMS
VDDo
PCLK
PRST*
VSSo
REQ*
VSSo
AD[21]
AD[18]
AD[13]
VSSo
AD[8]
AD[15]
PERR*
TRDY*
AD[1]
M66EN
AD[11]
CBE[1]
TDAT[4]
AD[0]
TM[2]
AD[3]
VSSo
AD[9]
AD[2]
VSSo
CBE[2]*
STOP*
AD[12]
AD[7]
AD[4]
DEVSEL*
AD[14]
CBE[0]*
AD[5]
FRAME*
SERR*
AD[10]
AD[6]
VSSo
8478_044
AD[22]
VDDo
IRDY*
AD[16]
AD[19]
IDSEL
AD[25]
VDDc
AD[23]
AD[26]
PAR
AD[20]
CBE[3]*
AD[27]
VGG
VDDi
AD[24]
AD[29]
VSSo
TM[0]
AD[17]
TDI
VSSo
AD[28]
TCLK[0]
TSYNC[5]
TCLK[4]
TDAT[0]
TSYNC[0]
TSYNC[4]
TM[1]
TDO
AD[30]
TCLK[2]
TDAT[7]
TCLK[6]
TSYNC[6]
TDAT[2]
TCLK[1]
TSYNC[1]
VSS
VSS
TCLK[3]
EAD[2]
TCLK[7]
VSS
VSS
VSS
EAD[5]
EAD[0]
TDAT[3]
TSYNC[3]
TSYNC[7]
TSYNC[2]
VSS
RDAT[4]
TRST*
RDAT[0]
RSYNC[0]
INTB*
EAD[4]
CN8478
RSYNC[2]
VDDi
RDAT[5]
ROOF[5]
INTA*
EAD[25]
EAD[1]
RSYNC[6]
RDAT[6]
RDAT[2]
RCLK[2]
AD[31]
T
8
HOLD(BR*)
EAD[29]
EAD[23]
EAD[18]
EAD[12]
VSSo
HLDA(BG*)
EAD[30]
EAD[24]
EAD[17]
EAD[11]
VSSo
RSYNC[3]
VSSo
ROOF[2]
RCLK[6]
GNT*
R
7
RDAT[7]
EBE[1]*
EINT*
RD*(DS*)
EAD[22]
EAD[13]
VSSo
EAD[8]
RDAT[3]
RCLK[3]
ROOF[6]
BGACK*
VDDc
VDDi
VSSo
EAD[3]
N
P
6
EBE[2]*
NC
VSSo
TCK
M
5
ROOF[7]
RCLK[7]
RSYNC[7]
NC
VSSo
C
4
100660E
Conexant
1-11
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-2. CN8478 PBGA Pin List
Pin
Number
Pin Label
Pin
Number
Pin Label
Pin
Number
Pin Label
A1
VSSo
C4
EBE[1]*
E15
EAD[0]
A2
RCLK[7]
C5
EBE[3]*
E16
EAD[2]
A3
ROOF[7]
C6
EINT*
F1
RDAT[2]
A4
NC
C7
ALE*(AS*)
F2
RSYNC[2]
A5
EBE[2]*
C8
RD*(DS*)
F3
RCLK[2]
A6
HOLD(BR*)
C9
EAD[26]
F4
VDDi
A7
ECLK
C10
EAD[22]
F13
VDDo
A8
EAD[29]
C11
EAD[19]
F14
TDAT[3]
A9
EAD[27]
C12
EAD[13]
F15
TCLK[7]
A10
EAD[23]
C13
EAD[6]
F16
TSYNC[3]
A11
EAD[20]
C14
VSSo
G1
RDAT[5]
A12
EAD[18]
C15
EAD[7]
G2
RCLK[5]
A13
EAD[16]
C16
EAD[8]
G3
ROOF[5]
A14
EAD[12]
D1
RDAT[3]
G4
RSYNC[5]
A15
EAD[10]
D2
RSYNC[3]
G7
VSS
A16
VSSo
D3
RCLK[3]
G8
VSS
B1
RSYNC[7]
D4
VSSo
G9
VSS
B2
VSSo
D5
ROOF[6]
G10
VSS
B3
NC
D6
VDDo
G13
TSYNC[7]
B4
EBE[0]*
D7
BGACK*
G14
TCLK[2]
B5
HLDA(BG*)
D8
EAD[31]
G15
TSYNC[2]
B6
WR*(R/ WR*)
D9
VDDc
G16
TDAT[7]
B7
EAD[30]
D10
EAD[25]
H1
RSYNC[1]
B8
EAD[28]
D11
VDDi
H2
RCLK[1]
B9
EAD[24]
D12
EAD[15]
H3
ROOF[1]
B10
EAD[21]
D13
VSSo
H4
VDDc
B11
EAD[17]
D14
EAD[4]
H7
VSS
B12
EAD[14]
D15
EAD[3]
H8
VSS
B13
EAD[11]
D16
EAD[5]
H9
VSS
B14
EAD[9]
E1
ROOF[2]
H10
VSS
B15
VSSo
E2
RSYNC[6]
H13
VDDc
B16
VGG
E3
RCLK[6]
H14
TSYNC[6]
C1
ROOF[3]
E4
RDAT[6]
H15
TCLK[6]
C2
RDAT[7]
E13
EAD[1]
H16
TDAT[2]
C3
VSSo
E14
TCLK[3]
J1
ROOF[4]
1-12
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
Pin
Number
Pin Label
Pin
Number
Pin Label
1.1 Pin Descriptions
Pin
Number
Pin Label
J2
RCLK[4]
M14
TM[0]
R2
VSSo
J3
RDAT[1]
M15
TM[1]
R3
AD[29]
J4
ROOF[0]
M16
TDAT[4]
R4
AD[26]
J7
VSS
N1
GNT*
R5
CBE[3]*
J8
VSS
N2
PRST*
R6
AD[21]
J9
VSS
N3
PCLK
R7
AD[19]
J10
VSS
N4
VSSo
R8
CBE[2]*
J13
TCLK[1]
N5
TDI
R9
TRDY*
J14
TDAT[1]
N6
VDDi
R10
STOP*
J15
TSYNC[1]
N7
AD[17]
R11
CBE[1]
J16
TDAT[6]
N8
VDDc
R12
AD[12]
K1
RCLK[0]
N9
PAR
R13
AD[9]
K2
RDAT[4]
N10
AD[13]
R14
AD[7]
K3
RSYNC[4]
N11
VDDo
R15
VSSo
K4
TRST*
N12
AD[8]
R16
AD[4]
K7
VSS
N13
VSSo
T1
VSSo
K8
VSS
N14
AD[1]
T2
VGG
K9
VSS
N15
AD[0]
T3
AD[27]
K10
VSS
N16
TM[2]
T4
AD[25]
K13
TCLK[5]
P1
AD[30]
T5
IDSEL
K14
TCLK[0]
P2
AD[31]
T6
AD[22]
K15
TDAT[5]
P3
VSSo
T7
AD[18]
K16
TSYNC[5]
P4
REQ*
T8
FRAME*
L1
RDAT[0]
P5
AD[24]
T9
DEVSEL*
L2
TCK
P6
AD[23]
T10
SERR*
L3
RSYNC[0]
P7
AD[20]
T11
AD[14]
L4
TMS
P8
AD[16]
T12
AD[10]
L13
VDDi
P9
IRDY*
T13
CBE[0]*
L14
TDAT[0]
P10
PERR*
T14
AD[6]
L15
TCLK[4]
P11
AD[15]
T15
AD[5]
L16
TSYNC[0]
P12
AD[11]
T16
VSSo
M1
INTA*
P13
M66EN
M2
INTB*
P14
VSSo
M3
TDO
P15
AD[3]
M4
VDDo
P16
AD[2]
M13
TSYNC[4]
R1
AD[28]
100660E
Conexant
1-13
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Figure 1-9. CN8474A PBGA Pinout Configuration (Top View)
2
1
3
VSSo
NC
NC
NC
VSSo
NC
D
E
RSYNC[3]
ROOF[2]
NC
G
J
RSYNC[2]
EAD[15]
RDAT[0]
VSS
VSS
VSS
NC
TCLK[1]
NC
TCLK[0]
VSS
TSYNC[0]
TM[1]
TM[0]
AD[17]
VDDi
AD[24]
REQ*
VDDc
AD[23]
AD[26]
PAR
AD[21]
IDSEL
AD[18]
VSSo
AD[8]
AD[15]
PERR*
TRDY*
AD[1]
M66EN
AD[11]
CBE[1]
NC
AD[0]
TM[2]
AD[3]
VSSo
AD[9]
AD[2]
VSSo
CBE[2]*
STOP*
AD[12]
AD[7]
AD[4]
DEVSEL*
AD[14]
CBE[0]*
AD[5]
FRAME*
SERR*
AD[10]
AD[6]
VSSo
8478_045
AD[22]
IRDY*
AD[16]
AD[19]
VDDo
AD[13]
AD[20]
CBE[3]*
AD[25]
NC
NC
TDAT[0]
VSSo
AD[27]
NC
NC
VDDi
TDI
AD[29]
VGG
TDAT[2]
TSYNC[1]
TDAT[1]
VSS
VSS
VSS
NC
NC
NC
VSSo
VSSo
TDAT[3]
TSYNC[3]
TSYNC[2]
VDDo
PRST*
AD[28]
NC
TMS
PCLK
AD[30]
NC
TCLK[2]
VSS
VSS
EAD[2]
VDDo
VSS
VSS
EAD[5]
EAD[0]
VDDc
TDO
INTB*
16
EAD[10]
EAD[4]
VSS
VSS
TRST*
RSYNC[0]
INTA*
15
TCLK[3]
VSS
VSS
NC
VSSo
T
EAD[25]
VSS
AD[31]
R
EAD[31]
ROOF[0]
RCLK[0]
14
EAD[16]
CN8474A
ROOF[1]
GNT*
P
VDDo
RCLK[1]
VDDc
RDAT[1]
N
EAD[20]
13
VDDi
TCK
M
12
RD*(DS*)
EAD[22]
EAD[13]
VSSo
EAD[8]
BGACK*
VDDc
VDDi
VSSo
EAD[3]
NC
RSYNC[1]
NC
L
EINT*
NC
NC
K
11
RCLK[2]
NC
NC
10
EAD[27]
NC
RDAT[2]
9
EAD[1]
NC
H
ECLK
NC
VSSo
NC
F
8
WR*(R/WR*)
EAD[28]
EAD[21]
EAD[14]
EAD[9]
VGG
EBE[3]*
ALE*(AS*)
EAD[26]
EAD[19]
EAD[6]
EAD[7]
EBE[1]*
RCLK[3]
RDAT[3]
7
HOLD(BR*)
EAD[29]
EAD[23]
EAD[18]
EAD[12]
VSSo
HLDA(BG*)
EAD[30]
EAD[24]
EAD[17]
EAD[11]
VSSo
EBE[0]*
ROOF[3]
6
EBE[2]*
NC
VSSo
C
5
NC
A
B
4
1-14
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Figure 1-10. CN8472A PBGA Pinout Configuration (Top View)
2
1
3
VSSo
NC
NC
NC
VSSo
NC
D
E
NC
NC
G
VSSo
J
EAD[15]
VSS
VSS
NC
NC
NC
TCLK[0]
VSS
VDDi
TDAT[0]
VSSo
AD[21]
AD[18]
AD[13]
VSSo
AD[8]
AD[15]
PERR*
TRDY*
AD[1]
M66EN
AD[11]
CBE[1]
NC
AD[0]
TM[2]
AD[3]
VSSo
AD[9]
AD[2]
VSSo
CBE[2]*
STOP*
AD[12]
AD[7]
AD[4]
DEVSEL*
AD[14]
CBE[0]*
AD[5]
FRAME*
SERR*
AD[10]
AD[6]
VSSo
8478_046
AD[22]
VDDo
IRDY*
AD[16]
AD[19]
IDSEL
AD[25]
VDDc
AD[23]
AD[26]
PAR
AD[20]
CBE[3]*
AD[27]
VGG
VDDi
AD[24]
REQ*
VSSo
TSYNC[0]
TM[1]
TM[0]
AD[17]
TDI
AD[29]
NC
NC
NC
VSSo
NC
NC
VDDo
PRST*
NC
TSYNC[1]
TDAT[1]
VSS
VSS
VSS
NC
NC
TCLK[1]
VSS
VSS
NC
NC
VSS
VSS
VSS
PCLK
AD[28]
EAD[2]
NC
VDDc
VSS
TMS
INTB*
EAD[5]
EAD[0]
NC
TDO
VSSo
EAD[4]
VSS
VSS
TRST*
RSYNC[0]
AD[30]
EAD[10]
NC
VSS
ROOF[0]
INTA*
16
NC
NC
AD[31]
T
EAD[25]
VSS
RCLK[1]
VDDc
RDAT[1]
GNT*
R
EAD[31]
NC
RCLK[0]
15
EAD[16]
CN8472A
ROOF[1]
RDAT[0]
14
VDDi
RSYNC[1]
N
P
EAD[20]
13
RD*(DS*)
EAD[22]
EAD[13]
VSSo
EAD[8]
BGACK*
VDDc
VDDi
VSSo
EAD[3]
VDDo
NC
TCK
M
12
VDDo
NC
NC
NC
L
11
NC
NC
K
EAD[27]
NC
NC
NC
10
EAD[1]
NC
H
9
NC
NC
F
ECLK
EINT*
NC
NC
8
WR*(R/WR*)
EAD[28]
EAD[21]
EAD[14]
EAD[9]
VGG
EBE[3]*
ALE*(AS*)
EAD[26]
EAD[19]
EAD[6]
EAD[7]
EBE[1]*
NC
7
HOLD(BR*)
EAD[29]
EAD[23]
EAD[18]
EAD[12]
VSSo
HLDA(BG)*
EAD[30]
EAD[24]
EAD[17]
EAD[11]
VSSo
EBE[0]*
NC
6
EBE[2]*
NC
VSSo
C
5
NC
A
B
4
100660E
Conexant
1-15
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Figure 1-11. CN8471A PBGA Pinout Configuration (Top View)
3
VSSo
NC
NC
NC
NC
EBE[0]*
NC
D
E
EBE[1]*
G
J
EAD[15]
VSS
VSS
VSS
NC
NC
NC
VDDi
TMS
TDAT[0]
NC
AD[28]
VSSo
VDDi
AD[24]
REQ*
AD[29]
AD[21]
AD[18]
AD[22]
VDDo
AD[13]
IRDY*
AD[16]
AD[19]
IDSEL
AD[25]
VDDc
AD[23]
AD[26]
PAR
AD[20]
CBE[3]*
AD[27]
TSYNC[0]
TM[1]
TM[0]
AD[17]
TDI
VSSo
NC
NC
VDDo
PRST*
NC
NC
TCLK[0]
VSS
TDO
AD[30]
NC
NC
VSS
VSS
NC
NC
NC
VSS
TRST*
RSYNC[0]
NC
NC
VSS
VSS
PCLK
EAD[2]
NC
VDDc
VSS
ROOF[0]
INTB*
EAD[5]
EAD[0]
NC
VSS
VSS
NC
VSSo
EAD[4]
NC
VSS
VDDc
NC
INTA*
16
EAD[10]
NC
VSS
NC
RCLK[0]
15
NC
VSS
NC
NC
VGG
1-16
EAD[25]
CN8471A
NC
VSSo
T
EAD[31]
VSS
AD[31]
R
EAD[16]
VDDi
NC
RDAT[0]
14
RD*(DS*)
EAD[22]
EAD[13]
VSSo
EAD[8]
BGACK*
VDDc
VDDi
VSSo
EAD[3]
VDDo
NC
GNT*
P
EAD[20]
13
VDDo
NC
NC
N
12
EAD[1]
TCK
M
11
NC
NC
L
10
EAD[27]
NC
NC
NC
K
EINT*
VSSo
NC
H
9
NC
NC
F
ECLK
NC
NC
8
WR*(R/WR*)
EAD[28]
EAD[21]
EAD[14]
EAD[9]
VGG
EBE[3]*
ALE*(AS*)
EAD[26]
EAD[19]
EAD[6]
EAD[7]
NC
NC
7
HOLD(BR*)
EAD[29]
EAD[23]
EAD[18]
EAD[12]
VSSo
HLDA(BG*)
EAD[30]
EAD[24]
EAD[17]
EAD[11]
VSSo
VSSo
NC
6
EBE[2]*
NC
VSSo
C
5
NC
A
B
4
VSSo
AD[8]
AD[15]
PERR*
TRDY*
AD[1]
M66EN
AD[11]
CBE[1]
NC
AD[0]
TM[2]
AD[3]
VSSo
AD[9]
AD[2]
VSSo
CBE[2]*
STOP*
AD[12]
AD[7]
AD[4]
DEVSEL*
AD[14]
CBE[0]*
AD[5]
FRAME*
SERR*
Conexant
AD[10]
AD[6]
VSSo
8478_047
2
1
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Figure 1-12. CN8478 Logic Diagram
Bus Grant Acknowledge I/O
Hold Acknowledge I
Hold Request O
Expansion Bus Interrupt I
Address Latch Enable O
Read Strobe O
Write Strobe/Read O
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
Out-Of-Frame
Clock
Synchronization
Data
JTAG Clock
JTAG Reset
JTAG Mode Select
JTAG Data Out
JTAG Data In
198
197
196
195
194
193
192
BGACK*
HLDA (BG*)
HOLD (BR*)
EINT*
ALE* (AS*)
RD* (DS*)
WR* (R/WR*)
I 207
I 208
1
I
2
I
7
I
8
I
9
I
I 10
I 17
I 18
I 19
I 20
I 25
I 26
I 29
I 30
3
I
4
I
5
I
6
I
I 11
I 12
I 15
I 16
I 21
I 22
I 23
I 24
I 31
I 32
I 33
I 34
I 35
I 36
I 37
O 38
I 39
ROOF[7]
RCLK[7]
RSYNC[7]
RDAT[7]
ROOF[6]
RCLK[6]
RSYNC[6]
RDAT[6]
ROOF[5]
RCLK[5]
RSYNC[5]
RDAT5]
ROOF[4]
RCLK[4]
RSYNC[4]
RDAT[4]
ROOF[3]
RCLK[3]
RSYNC[3]
RDAT[3]
ROOF[2]
RCLK[2]
RSYNC[2]
RDAT[2]
ROOF[1]
RCLK[1]
RSYNC[1]
RDAT[1]
ROOF[0]
RCLK[0]
RSYNC[0]
RDAT[0]
TCK
TRST*
TMS
TDO
TDI
43
45
46
60
75
76
79
80
83
84
86
PCLK
PRST*
GNT*
IDSEL
FRAME*
IRDY*
TRDY*
DEVSEL*
STOP*
PERR*
PAR
AD[31:0]
M66EN
Clock I
Reset I
Grant I
Initialization Device Select I
Frame I/O
Initiator Ready I/O
Target Ready I/O
Device Select I/O
Stop I/O
Parity Error I/O
Parity I/O
Address and Data Bus I/O
M66EN I
(3)
98
Expansion Bus
Interface
ECLK 190
EBE[3:0]* (1)
EAD[31:0] (2)
O Clock
O Expansion Bus Byte Enable
I/O Expansion Bus Address/Data
Serial Interface
TCLK[7] 140
I Clock
I Synchronization
O Data
TCLK[6] 131
I Clock
I Synchronization
O Data
TCLK[5] 125
I Clock
I Synchronization
O Data
TCLK[4] 117
I Clock
I Synchronization
O Data
TCLK[3] 143
I Clock
I Synchronization
O Data
TCLK[2] 136
I Clock
I Synchronization
O Data
TCLK[1] 128
I Clock
I Synchronization
O Data
TCLK[0] 122
I Clock
I Synchronization
O Data
Receive Serial
Channel Group
7
Transmit Serial TSYNC[7] 149
Channel Group
TDAT[7] 138
7
Receive Serial
Channel Group
6
Transmit Serial TSYNC[6] 130
Channel Group
TDAT[6] 129
6
Receive Serial
Channel Group
5
Transmit Serial TSYNC[5] 124
Channel Group
TDAT[5] 123
5
Receive Serial
Channel Group
4
Transmit Serial TSYNC[4] 116
Channel Group
TDAT[4] 115
4
Receive Serial
Channel Group
3
Transmit Serial TSYNC[3] 142
Channel Group
TDAT[3] 141
3
Receive Serial
Channel Group
2
Transmit Serial TSYNC[2] 135
Channel Group
TDAT[2] 134
2
Receive Serial
Channel Group
1
Transmit Serial TSYNC[1] 127
Channel Group
TDAT[1] 126
1
Receive Serial
Channel Group
0
Transmit Serial TSYNC[0] 121
Channel Group
TDAT[0] 120
0
Boundary Scan
Test Signal
TM[0] 114
TM[1] 113
TM[2] 112
Scan Chain
Test Access
Host (PCI)
Interface
INTB* 40
INTA* 41
CBE[3:0]* (4)
REQ* 47
SERR* 85
I
I
I
Scan Enable
Scan Mode Bit 1
Scan Mode Bit 2
O
O
O
O
O
PCI Interrupt B
PCI Interrupt A
Command and Byte Enables
Request
System Error
8478_004
NOTE(S):
(1)
(2)
(3)
(4)
(5)
EBE [3:0]* pin numbers are 199-200, 203-204.
EAD [31:0] pin numbers are 144-146, 149-152, 145-155, 158-163, 166-170, 173-174, 176-180, 183-184, 187-189.
AD [31:0] pin numbers are 48-51, 54, 56-58, 61-62, 65-66, 69-72, 88, 90-94, 97, 99, 101-103, 105-109.
CBS [3.0]* pin numbers are 59, 74, 87,100.
An active low signal is denoted by a trailing asterisk (*).
100660E
Conexant
1-17
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
1.1 Pin Descriptions
Multichannel Synchronous Communications Controller (MUSYCC™)
Table 1-3. I/O Pin Types
I/O
Definition
I
Input. High impedance, TTL.
O
Output. CMOS.
I/O
Input/Output. TTL input/CMOS output.
t/s
Three-state. Bidirectional three-state I/O pin.
s/t/s
Sustained three-state. This is an active-low, three-state signal owned by only one driver at a time. The driver
that drives an s/t/s signal low must drive it high for at least one clock cycle before allowing it to float. A pullup
is required to sustain the deaserted value.
o/d
Open drain.
NOTE(S): All outputs are CMOS drive levels and can be used with CMOS or TTL logic.
1-18
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (1 of 6)
MQFP
Pin No.
Expansion Bus Interface
190
Pin Label
Signal Name
I/O
Definition
ECLK
Expansion Bus Clock
t/s O
ECLK is an inverted version of the PCI clock applied at the PCLK
input.
144-146,
149-152,
154-155,
158-163,
166-170,
173-174,
176-180,
183-184,
187-189
EAD[31:0]
Expansion Bus
Address and Data
t/s I/O
EAD[31:0] is a multiplexed address/data bus. During the address
phase, pins EAD[17:0] contains meaningful address information.
It is the same address as PCI AD[19:2] for the corresponding
cycle.
Pins EAD[31:18] are driven to 0 during the address phase.
This is because those upper bits are compared, during the PCI
address phase, to the value in the relocatable EBUS Base
Address register to determine if the PCI cycle is in fact
addressing into MUSYCC EBUS space.
During data phase of an EBUS access cycle, the PCI signals
AD[31:0] are transferred to the EBUS signal lines EAD[31:0]
unaltered.
199, 200,
203, 204
EBE[3:0]*
Expansion Bus
Byte Enables
t/s O
EBE* contains the same information as the PCI byte enables but
is driven in chip select style protocol used as active-low chip
selects when MUSYCC is connected to more than one byte-wide
device. All PCI accesses with byte lane 0’s byte enable asserted
would go to the byte-wide device connected to EAD[7:0].
Likewise, for byte lanes 1, 2, and 3 and EAD[15:8], EAD[23:16],
and EAD[31:24], respectively.
Only the CBE[3:0]* signals from the PCI data phase
(byte-enable signals and not the command signals from the PCI
address phase) are transferred to the EBE[3:0]* signal lines.
EBE* is held high during all other phases of PCI access cycles.
192
WR*
(R/WR*)
Write Strobe
t/s O
High-to-low transition enables write data from MUSYCC into
peripheral device. Rising edge defines write. (In Motorola mode,
R/WR* is held high throughout read operation and held low
throughout write operation. Determines meaning of DS* strobe.)
193
RD*
(DS*)
Read Strobe
t/s O
High-to-low transition enables read data from peripheral into
MUSYCC. Held high throughout write operation. (In Motorola
mode, DS* transitions low for both read and write operations
and is held low throughout the operation.
194
ALE*
(AS*)
Address Latch Enable
t/s O
High-to-low transition indicates that EAD[31:0] bus contains
valid address. Remains asserted low through the data phase of
the EBUS access. (In Motorola mode, high-to-low transition
indicates EBUS contains valid address. Remains asserted for the
entire access cycle.)
195
EINT*
Expansion Bus
Interrupt
I
196
HOLD
(BR*)
Hold Request
(Bus Request)
t/s O
197
HLDA
(BG*)
Hold Acknowledge
(Bus Grant)
198
BGACK*
100660E
Bus Grant
Acknowledge
I
t/s O
EINT* transfers interrupts from local devices to the PCI INTB*
pin.
When asserted, MUSYCC requests control of the EBUS.
When asserted, MUSYCC has access to the EBUS. It is held
asserted when there are no other masters connected to the bus,
or asserted as a handshake mechanism to control EBUS
arbitration.
When asserted, MUSYCC acknowledges to the bus arbiter that
the bus grant signal was detected and a bus cycle will be
sustained by MUSYCC until this signal is deasserted.
Conexant
1-19
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (2 of 6)
Serial Interface
MQFP
Pin No.
Pin Label
Signal Name
117, 122,
125, 128,
131, 136,
140, 143
TCLK[7:0]
116, 121,
124, 127,
130, 135,
139, 142
TSYNC[7:0]
115, 120,
123, 126,
129, 134,
138, 141
TDAT[7:0]
Transmit Data
4, 8, 12,
18, 22,
26, 32,
208
RCLK[7:0]
Receive Clock (1)
1, 5, 9,
15, 19,
23, 29, 33
1-20
I/O
Definition
Transmit Clock (1)
I
Controls the rate at which data is transmitted. Synchronizes
transitions for TDATx and sampling of TSYNCx. Valid frequencies
from DC to 8.192 ±10% MHz. Schmitt trigger driver.
Transmit
Synchronization (1)
I
TSYNC is sampled on the specified active edge of the
corresponding transmit clock, TCLKx. See TSYNC_EDGE bit field
in Table 5-12.
As TSYNCx signal transitions low-to-high, start of a transmit
frame is indicated. For T1 mode, the corresponding data bit
latched out during the same bit time period (but not necessarily
the same clock edge) is the F-bit of the T1 frame. For E1 modes,
the corresponding data bit latched out during the same bit time
period (but not necessarily the same clock edge) is bit 0 of the E1
frame. For Nx64 mode, the corresponding data bit is latched out
4-bit time periods later and is bit 0 of the Nx64 frame.
TSYNCx must remain asserted high for a minimum of a setup
and hold time relative to the active clock edge for this signal. If
the flywheel mechanism is used, no other synchronization signal
is required, because MUSYCC tracks the start of each
subsequent frame. If the flywheel mechanism is not used, then a
subsequent low-to-high assertion is required to indicate the start
of the next frame. See SFALIGN bit field in Table 5-10.
t/s O
Serial data latched out on active edge of transmit clock, TCLKx. If
channel is unmapped to time slot, data bit is considered invalid
and MUSYCC outputs either three-state signal or logic 1
depending on value of bit field TRITX in Table 5-12.
I
Active edge samples RDATx and RSYNCx. Valid frequencies from
DC to 8.192 ± 10% MHz. Schmitt trigger driver.
I
RSYNCx is sampled on the specified active edge of the
corresponding receive clock, RCLKx. See RSYNC_EDGE bit field
in Table 5-12.
As RSYNCx signal transitions low-to-high, start of a receive
frame is indicated. For T1 mode, the corresponding data bit
sampled and stored during the same bit time period (but not
necessarily the same clock edge) is the F-bit of the T1 frame. For
E1 modes, the corresponding data bit sampled and stored during
the same bit time period (but not necessarily the same clock
edge) is bit 0 of the E1 frame. For Nx64 mode, the corresponding
data bit sampled and stored during the same bit time period (but
not necessarily the same clock edge) is bit 0 of the Nx64 frame.
RSYNCx must be asserted high for a minimum of a setup and
hold time relative to the active clock edge for this signal. If the
flywheel mechanism is used, no other synchronization signal is
required, because MUSYCC tracks the start of each subsequent
frame. If the flywheel mechanism is not used, a subsequent
low-to-high assertion is required to indicate the start of the next
frame. See SFALIGN bit field in Table 5-10.
RSYNC[7:0] Receive
Synchronization (1)
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (3 of 6)
Serial Interface (Continued)
MQFP
Pin No.
Pin Label
Signal Name
I/O
Definition
2, 6, 10,
16, 20,
24, 30, 34
RDAT[7:0]
Receive Data (1)
I
Serial data sampled on active edge of receive clock, RCLKx.
If channel is mapped to a time slot, input bit is sampled and
transferred to memory. If channel is unmapped to time slot, data
bit is considered invalid, and MUSYCC ignores received sample.
3, 7, 11,
17, 21,
25, 31,
207
ROOF[7:0]
Receiver
Out-of-Frame (1)
I
ROOFx is sampled on the specified active edge of the
corresponding receive clock, RCLKx. See ROOF_EDGE bit field in
Table 5-12.
As ROOFx signal transitions from low to high, an
Out-of-Frame (OOF) condition is indicated. As long as ROOFx is
asserted, the received serial data is considered OOF.
Depending on the state of OOFABT bit field in Table 5-10,
receive bit processing may be disabled for the entire channel
group (all channels disabled) while ROOFx remains asserted.
Upon deassertion of ROOFx, bit-level processing resumes for
all affected channels. If the flywheel mechanism is used, no other
synchronization signal is required, because MUSYCC tracks the
start of each subsequent frame during the OOF period. If the
flywheel mechanism is not used, then a subsequent RSYNCx
assertion is required to indicate the start of the next frame. See
SFALIGN bit field in Table 5-10.
100660E
Conexant
1-21
CN8478/CN8474A/CN8472A/CN8471A
1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (4 of 6)
MQFP
Pin No.
48-51, 54,
56-58, 61,
65-66,
69-72, 88,
90-94, 97,
99,
101-103,
105-109
Pin Label
AD[31:0]
Signal Name
PCI Address
and Data
I/O
t/s I/O
AD[31:0] is a multiplexed address/data bus. A PCI transaction
consists of an address phase during the first clock period
followed by one or more data phases. AD[7:0] is the LSB.
43
PCLK
PCI Clock
I
PCLK provides timing for all PCI transitions. All PCI signals
except PRST*, INTA*, and INTB* are synchronous to PCLK and
are sampled on the rising edge of PCLK. MUSYCC supports a
PCI clock up to 66 MHz.
45
PRST*
PCI Reset
I
This input resets all functions on MUSYCC.
59, 74,
87, 100
CBE[3:0]*
PCI Command
and Byte Enables
t/s I/O
During the address phase, CBE[3:0]* contain command
information; during the data phases, these pins contain
information denoting which byte lanes are valid.
PCI commands are defined as follows:
Oh
1h
6h
7h
Ah
Bh
Ch
Dh
Eh
Fh
PCI Interface
1-22
Definition
CBE[3:0]
0000b
0001b
0110b
0111b
1010b
1011b
1100b
1101b
1110b
1111b
Command Type
Interrupt Acknowledge
Special Cycle
Memory Read
Memory Write
Configuration Read
Configuration Write
Memory Read Multiple
Dual Address Cycle
Memory Read Line
Memory Write and Invalidate
86
PAR
PCI Parity
t/s I/O
The number of 1s on PAR, AD[31:0], and CBE[3:0]* is an even
number. PAR always lags AD[31:0] and CBE* by one clock.
During address phases, PAR is stable and valid one clock after
the address; during the data phases it is stable and valid one
clock after TRDY* on reads and one clock after IRDY* on writes.
It remains valid until one clock after the completion of the data
phase.
75
FRAME*
PCI Frame
s/t/s
I/O
FRAME* is driven by the current master to indicate the beginning
and duration of a bus cycle. Data cycles continue as FRAME*
stays asserted. The final data cycle is indicated by the
deassertion of FRAME*. For a non-burst, one-data-cycle bus
cycle, this pin is only asserted for the address phase.
76
IRDY*
PCI Initiator Ready
s/t/s
I/O
IRDY* asserted indicates the current master’s readiness to
complete the current data phase.
79
TRDY*
PCI Target Ready
s/t/s
I/O
TRDY* asserted indicates the target’s readiness to complete the
current data phase.
83
STOP*
PCI Stop
s/t/s
I/O
STOP* asserted indicates the selected target is requesting the
master to stop the current transaction.
Conexant
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1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (5 of 6)
MQFP
Pin No.
Signal Name
I/O
80
DEVSEL*
PCI Device Select
s/t/s
I/O
60
IDSEL
PCI Initialization
Device Select
I
85
SERR*
System Error
o/d O
Any PCI device can assert SERR* to indicate a parity error on the
address cycle or parity error on the data cycle of a special cycle
command or any other system error where the result will be
catastrophic. MUSYCC only asserts SERR* if it detects a parity
error on the address cycle.
Since SERR* is not an s/t/s signal, restoring it to the
deasserted state is done with a weak pullup (same value as used
for s/t/s).
MUSYCC does not input SERR*. It is assumed that the host
will reset MUSYCC in the case of a catastrophic system error.
84
PERR*
Parity Error
s/t/s
I/O
PERR* is asserted by the agent receiving data when it detects a
parity error on a data phase. It is asserted one clock after PAR is
driven, which is two clocks after the AD and CBE* parity was
checked.
MUSYCC generates the PERR Interrupt Descriptor toward the
host under the following conditions:
• MUSYCC masters a PCI cycle.
• After supplying data during the data phase of the cycle,
MUSYCC detects this signal being asserted by the agent
receiving the data.
• MUSYCC asserts the PCI read cycle and generates the
PERR Interrupt Descriptor toward the host under the
following conditions:
• MUSYCC masters a PCI read cycle.
• After receiving the data during the data phase of the
cycle, MUSYCC calculates that a parity error has
occurred.
41
INTA*
PCI MUSYCC
Interrupt
o/d O
INTA* is driven by MUSYCC to indicate a MUSYCC Layer 2
interrupt condition to the host processor.
40
INTB*
PCI Expansion Bus
Interrupt
o/d O
INTB* is driven by MUSYCC to notify the host processor of an
interrupt pending from the EBUS.
47
REQ*
PCI Bus Request
t/s O
MUSYCC drives REQ* to notify the PCI arbiter that it desires to
master the bus. Every master in the system has its own REQ*.
46
GNT*
PCI Bus Grant
I
The PCI bus arbiter asserts GNT* when MUSYCC is free to take
control of the bus, assert FRAME*, and execute a bus cycle.
Every master in the system has its own GNT*.
98
M66EN
66 MHz Enable
I
When asserted, M66EN indicates the system is operating at a
66 MHz PCI clock rate. Otherwise, it is operating at a 33 MHz or
less clock rate. This pin is a no-connect on Revision A and B
devices.
PCI Interface
Pin Label
100660E
Definition
When asserted, DEVSEL* indicates that the driving device has
decoded its address as the target of the current cycle.
This input is used to select MUSYCC as the target for
configuration read or write cycles.
Conexant
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1.0 System Description
Multichannel Synchronous Communications Controller (MUSYCC™)
1.1 Pin Descriptions
Table 1-4. CN8478 Hardware Signal Definitions (6 of 6)
Boundary Scan and Test Access
MQFP
Pin No.
Signal Name
I/O
Definition
35
TCK
JTAG Clock
I
Clock in the TDI and TMS signals and clock out TDO signal.
36
TRST*
JTAG Reset
I
An active-low input that resets the JTAG state machine. This pin
should be pulled low in normal operation.
37
TMS
JTAG Mode Select
I
The test signal input decoded by the TAP controller to control
test operations.
38
TDO
JTAG Data Output
t/s O
The test signal that transmits serial test instructions and tests
data.
39
TDI
JTAG Data Input
I
The test signal that receives serial test instructions and tests
data.
Test Mode
I
Encodes test modes.
These pins have internal pull-downs and may be left open by
the system designer.
112-114
Power and Ground
Pin Label
TM[0]
TM[1]
TM[2]
TM[0]
TM[1]
TM[2]
0
0
0
Normal Operation. Tie to ground.
1
1
1
All outputs three-stated.
(2)
VDDc
VDDi(3)
VDDo
VGG
Power
–
19 pins are provided for power. Four VDDc (core), four VDDi
(input), nine VDDo (output), and two VGG (5 V-tolerant supply).
The VDDc require 2.5 V +/- 5%, the VDDi and VDDo require 3.3 V
+/- 5%, and the VGG require 5 V +/- 5%. The recommended
power ramp sequence is VDDi and VDDo together, then VDDc at
t = 0+. VGG can be powered at any time.
(3)
VSS(3)
VSSo
Ground
–
27 pins are provided for ground, 0 V DC. 10 VSS (core and input)
and 17 VSSo (output).
NOTE(S):
(1)
(2)
(3)
(4)
These pins have internal pullups and may be left open by the system designer.
VDDc Pin Numbers: 27, 77, 132, 185
VDDi Pin Numbers: 13, 67, 118, 171
VDDo Pin Numbers: 42, 63, 81, 95, 110, 147, 164, 181, 201
VGG Pin Numbers: 52, 156
VSS Pin Numbers: 14, 28, 53, 68, 78, 119, 133, 157, 172, 186
VSSo Pin Numbers: 44, 55, 64, 73, 82, 89, 96, 104, 111, 137, 148, 153, 165, 175, 182, 191, 202
An active low signal is denoted by a trailing asterisk (*).
1-24
Conexant
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2
2.0 Host Interface
MUSYCC’s host interface performs the following major functions:
•
•
•
Transfers data between the serial interface and shared memory over the
PCI bus
Bridges system host processors to the devices connected to the EBUS
Stores configuration state information
Figure 2-1 illustrates the host interface block diagram.
Figure 2-1. Host Interface Functional Block Diagram
Host
Interface
Device
Configuration
Registers
Tx Control
Tx Data
Rx Control
Rx Data
Interrupts
Serial
Interface
Clock
PCI
Bus
Control
Data
PCI
Interface
Interrupt
PCI
Configuration
Space
(Function 0)
Clock
Control
Data
Local
Expansion
Bus (EBUS)
Interrupt
PCI
Configuration
Space
(Function 1)
8478_005
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.1 PCI Interface
2.1 PCI Interface
The host interface in MUSYCC is compliant with the PCI Local Bus
Specification (Revision 2.1, June 1, 1995). MUSYCC provides a PCI interface
specific to 3.3 V and 33 or 66 MHz operation.
NOTE:
The PCI Local Bus Specification (Revision 2.1, June 1, 1995) is an
architectural, timing, electrical, and physical interface standard providing
the parameters for a device to connect with processor and memory
systems.
The host interface can act as both a PCI master and PCI slave, and contains
MUSYCC’s PCI configuration space and internal registers. When MUSYCC
must access shared memory, it masters the PCI bus and completes the memory
cycles without external intervention.
MUSYCC provides the host with a PCI bridge to an on-device EBUS, and
behaves as a PCI slave when providing this access.
MUSYCC is a multifunction PCI agent. One function is mapped to the layer 2
HDLC control logic; a second function is mapped to the layer 1 physical interface
for the expansion bus pins.
2.1.1 PCI Initialization
Generally, when a system initializes a module containing a PCI device, the
configuration manager reads the configuration space of each PCI device on a PCI
bus. Hardware signals select a specific PCI device based on a bus number, a slot
number, and a function number. If the addressed device (via signal lines) responds
to the configuration cycle by claiming the bus, that function’s configuration space
is read out from the device during the cycle. Because any PCI device can be a
multifunction device, every supported function’s configuration space must be
read from the device. Based on the information read, the configuration manager
assigns system resources to each supported function within the device.
Sometimes new information must be written to the function’s configuration
space; this is accomplished with a configuration write cycle.
MUSYCC is a multifunction device with device-resident memory to store the
required configuration information. MUSYCC supports Function 0 and
Function 1 and, as such, only responds to Function 0 and Function 1
configuration cycles, defined as listed below:
•
•
2-2
Function 0: All HDLC processing as an HDLC network controller. Can
master the PCI bus or respond to slave accesses from another bus master.
Function 1: EBUS bridge to local devices. Responds only when another
bus master performs a memory access into the Function 1 address range.
Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.1 PCI Interface
2.1.2 PCI Bus Operations
MUSYCC behaves either as a PCI master or a PCI slave at any time and switches
between these modes as required during device operation.
As a PCI slave, MUSYCC responds to the following PCI bus operations:
•
•
•
•
•
•
•
Memory Read
Memory Write
Configuration Read
Configuration Write
Memory Read Multiple (treated like Memory Read in slave mode)
Memory Read Line (treated like Memory Read in slave mode)
Memory Write and Invalidate (treated like Memory Write)
All other PCI cycles are ignored by MUSYCC. Only memory cycles are
mapped to operations on the EBUS.
As a PCI-master, MUSYCC generates the following PCI bus operations:
•
•
•
Memory Read Multiple (generated only in master mode)
Memory Write
Dual Address Cycle
2.1.3 PCI Configuration Space
This section describes how MUSYCC implements the required PCI configuration
register space to provide configuration registers. These registers satisfy the needs
of current and anticipated system configuration mechanisms, without specifying
those mechanisms or otherwise placing constraints on their use. The
configuration registers provide the following functions:
•
•
•
Full device relocation, including interrupt binding
Installation, configurations, and booting without user intervention
System address map construction by device-independent software
MUSYCC responds only to Type 0 configuration cycles. Type 1 cycles, which
pass a configuration request on to another PCI bus, are ignored.
MUSYCC is a two-function PCI agent; therefore, it must implement
configuration space for both functions.
The PCI controller in MUSYCC responds to configuration and memory
cycles, but only memory cycles cause bus activity on the EBUS.
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.1 PCI Interface
The address phase during a MUSYCC configuration cycle indicates the
function number and register number being addressed which can be decoded by
observing the status of the address lines AD[31:0]. Figure 2-2 shows the address
lines during the configuration cycle.
Figure 2-2. Address Lines During Configuration Cycle
11 10
Don't
Care
8 7
3-Bit
Function
Number (1)
2 1
Bit
0 Number
6-Bit
2-Bit
Register
Type
(2)
Number
Number (3)
8478_006
31
NOTE(S):
(1)
(2)
(3)
MUSYCC supports Functions 0 and 1.
MUSYCC supports Registers 0 through 15, inclusive.
MUSYCC supports Type 0 configuration cycles.
The value of the signal lines AD[10:8] selects the function being addressed.
MUSYCC supports Functions 0 and 1 and will not respond if another function is
selected.
The value of the signal lines AD[7:2] during the address phase of
configuration cycles selects the register of the configuration space to access.
Valid values are 0–15. Accessing registers outside this range results in an all 0s’
value being returned on reads, and no action being taken on writes.
The value of the signal lines AD[1:0] must be 00b for MUSYCC to respond. If
these bits are 0 and the IDSEL signal line is asserted, then MUSYCC will respond
to the configuration cycle.
Although there are two separate configuration spaces, one for Function 0 and
one for Function 1, some internal registers are shared between the two spaces.
The Base Code register contains the Class Code, Sub Class Code, and
Register Level Programming Interface registers. Tables 2-1 and 2-2 list
Function 0 and Function 1 configuration spaces.
2-4
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.1 PCI Interface
Function Number 0
Table 2-1. Function 0 Configuration Space
Register
Number
Byte Offset
(Hex)
0
00h
Device ID(1)
Vendor ID(1)
1
04h
Status
Command
2
08h
3
0Ch
4
10h
MUSYCC Base Address Register (BAR)
5
14h
—
—
—
Reserved
14
38h
—
15
3Ch
31
24
16
8
Base Code
Reserved
Revision ID(1)
Header Type
Max Latency
0
LatencyTimer
Min Grant
Reserved
Interrupt Pin
Interrupt Line
8
0
NOTE(S):
(1)
Registers shared between Function 0 and 1.
Function Number 1
Table 2-2. Function 1 Configuration Space
Register
Number
Byte Offset
(Hex)
0
00h
Device ID(1)
Vendor ID(1)
1
04h
Status
Command
2
08h
3
0Ch
4
10h
EBUS Base Address Register (BAR)
5
14h
—
—
—
Reserved
14
38h
—
15
3Ch
31
24
16
Base Code
Reserved
Revision ID(1)
Header Type
Reserved
Reserved
Interrupt Pin
Reserved
Interrupt Line
NOTE(S):
(1)
Registers shared between Function 0 and 1.
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2.0 Host Interface
2.1 PCI Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
In summary, both configuration spaces have unique registers except for the
Device ID, Vendor ID, and Revision ID, which are shared between the
configuration spaces for Functions 0 and 1.
MUSYCC is a multifunction device with two sources of interrupts: the HDLC
controller interrupts and the expansion bus physical layer interrupts. MUSYCC
uses the INTA* pin for HDLC controller interrupts and the INTB* pin for
interrupts generated by devices on the expansion bus connected to the EINT* pin.
All writable bits in the configuration space are reset to 0 by the hardware
reset, PRST* asserted. After reset, MUSYCC is disabled and responds only to
PCI configuration write and PCI configuration read cycles. Write cycles to
reserved bits and registers have no effect. Read cycles to reserved bits always
result in 0 being read.
2-6
Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
2.2 PCI Configuration Registers
2.2.1 Function 0 Network Controller—PCI Master and Slave
MUSYCC provides the necessary configuration space for a PCI bus controller to
query and configure MUSYCC’s PCI interface. PCI configuration space consists
of a device-independent header region (64 bytes) and a device-dependent header
region (192 bytes). MUSYCC provides the device-independent header section
only. Access to the device-dependent header region results in 0s being read, with
no effect on writes.
There are three types of registers available in MUSYCC:
Read-Only (RO): Returns a fixed bit pattern if the register is used, or a 0 if
the register is unused or reserved.
2. Read-Resettable (RR): Can be reset to 0 by writing a 1 to the register.
3. Read/Write (RW): Retains the value last written to it.
1.
MUSYCC’s Function 0 PCI Configuration Space has 16 dword registers.
Tables 2-3 through 2-9 define these registers.
Register 0, Address 00h
Table 2-3. Register 0, Address 00h
Bit
Field
Name
Reset
Value
Type
Description
31:16
Device ID(1)
847xh
RO
This unique device identification is assigned by the
manufacturer. This field always returns the value 847xh where x
can be 1, 2, 4, or 8 depending on the 32, 64, 128, or 256 channel
version of the device, respectively.
15:0
Vendor ID(1)
14F1h
RO
The unique vendor identification assigned to the manufacturer.
This field always returns the value 14F1h.
NOTE(S):
(1)
Registers shared between Function 0 and 1.
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Register 1, Address 04h
The Status register records status information for PCI bus related events. The
Command register provides coarse control to generate and respond to PCI
commands.
At reset, MUSYCC sets the bits in this register to 0, meaning MUSYCC is
logically disconnected from the PCI bus for all cycle types except configuration
read and configuration write cycles.
Table 2-4. Register 1, Address 04h (1 of 2)
Bit
Field
31
Name
Type
Description
0
RR
Detected Parity Error. This bit is set by MUSYCC whenever it
detects a parity error on a data phase when MUSYCC is a target,
even if parity error response is disabled.
30
0
RR
Detected System Error. This bit is set by MUSYCC whenever it
asserts SERR*.
29
0
RR
Received Master Abort. This bit is set by MUSYCC whenever a
MUSYCC-initiated cycle is terminated with master-abort.
28
0
RR
Received Target Abort. MUSYCC sets this bit when a
MUSYCC-initiated cycle is terminated by a target-abort.
27
0
RO
Unused.
26:25
01b
RO
DEVSEL* Timing. Indicates MUSYCC is a medium-speed PCI
device. This means the longest time it will take MUSYCC to
return DEVSEL* when it is a target of 3 clock cycles.
24
0
RR
Data Parity Detected. MUSYCC sets this bit when three
conditions are met:
1. MUSYCC asserts PERR* or observes PERR*.
2. MUSYCC is the master for that transaction.
3. The Parity Error Response bit in this register is set.
23
1b
RO
Fast Back-to-Back Capable. Read Only. Indicates that when
MUSYCC is a target, it is capable of accepting fast back-to-back
transactions when the transactions are not to the same agent.
22
0
RO
Unused.
21
I
RO
Indicates the device is 66 MHz capable. This bit is set by
Revision C and later devices.
20:16
0
RO
Unused.
2-8
Status
Reset
Value
Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Table 2-4. Register 1, Address 04h (2 of 2)
Bit
Field
15:10
Name
Command
Reset
Value
Type
Description
0
RO
Unused.
9
0
RW
Fast back-to-back mode is not supported.
8
0
RW
SERR* enable.
If 1, disables MUSYCC’s SERR* driver.
If 0, enables MUSYCC’s SERR* driver and allows reporting of
address parity errors.
7
0
RO
Wait cycle control. MUSYCC does not support address stepping.
6
0
RW
Parity error response. This bit controls MUSYCC’s Function 0
response to parity errors.
If 1, MUSYCC takes normal action when a parity error is
detected on a cycle with Function 0 as the target.
If 0, MUSYCC ignores parity errors.
5
0
RO
VGA palette snoop. Unused.
4
0
RO
Memory write and invalidate. The only write cycle type MUSYCC
generates is memory write.
3
0
RO
Special cycles. Unused. MUSYCC ignores all special cycles.
2
0
RW
Bus master.
If 1, MUSYCC is permitted to act as bus master.
If 0, MUSYCC is disabled from generating PCI accesses.
1
0
RW
Memory space. Access control.
If 1, enables MUSYCC to respond to Function 0 memory
space access cycles.
If 0, disables MUSYCC’s response.
0
0
RO
I/O space accesses. MUSYCC does not contain any I/O space
registers.
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
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Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Register 2, Address 08h
This location contains the Class Code and Revision ID registers. The Class Code
register contains the Base Class Code, Sub-Class Code, and Register Level
Programming Interface fields, used to specify the generic function of MUSYCC.
The Revision ID register denotes the version of the device.
Table 2-5. Register 2, Address 08h
Bit
Field
Name
31:24
23:16
Class Code
15:8
7:0
Revision ID(1)
Reset
Value
Type
02h
RO
Base Class Code: Network Controller.
80h
RO
Sub-Class Code: Other Network Controller.
0
RO
Register Level Programming Interface: Indicates there is nothing
special about programming MUSYCC.
01h
RO
Denotes the revision number of MUSYCC. Rev A = 0Ah,
Rev B = 0Bh, Rev C = 0Ch, etc.
Description
NOTE(S):
(1)
2-10
Registers shared between Function 0 and 1.
Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Register 3, Address 0Ch
Table 2-6. Register 3, Address 0Ch
Bit
Field
Name
Reset
Value
Type
Description
31
Built-In Self Test (BIST)
Capable
1
RO
Returns 1 if device supports BIST. Returns 0 if it does not
support BIST.
30
Start BIST
0
RW
Writes 1 to invoke BIST. Device resets the bit when BIST is
complete. Software should fail the device if BIST is not complete
after two seconds.
29:27
Reserved
0
RO
Unused.
26
BIST Error in the
Interrupt Queue
—
RO
After “Start BIST” bit gets reset, this bit indicates if there were
any errors in the interrupt queue RAM areas.
25
BIST Error in the
Transmitter
—
RO
After “Start BIST” bit gets reset, this bit indicates if there were
any errors in the transmit queue RAM areas.
24
BIST Error in the
Receiver
—
RO
After “Start BIST” bit gets reset, this bit indicates if there were
any errors in the receive queue RAM areas.
23:16
Header Type
80h
RO
MUSYCC is a multifunction device with the standard layout of
configuration register space.
15:11
Latency Timer
0
RW
0
RO
The latency timer is an 8-bit value that specifies the maximum
number of PCI clock cycles that MUSYCC can keep the bus after
starting the access cycle by asserting its FRAME*. The latency
timer ensures that MUSYCC has a minimum time slot for it to
own the bus, but places an upper limit on how long it will own
the bus.
0
RO
10:8
7:0
Reserved
Unused.
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Register 4, Address 10h
Table 2-7. Register 4, Address 10h
Bit
Field
Reset
Value
Type
Description
0
RW
Allows for 1 MB bounded PCI bus address space to be blocked
off as MUSYCC space. MUSYCC responds as a PCI slave with
DEVSEL* to all bus cycles whose address bits 31:20 match the
value of bits 31:20 of this register, and whose upper address bits
are non-zero, and memory space is enabled in the Function 0
Register 1, memory space bit field.
Reads to addresses within this space that are not
implemented will read back 0; writes have no effect.
19:4
0
RO
When appended to bits 31:20, these bits specify a 1 MB bound
memory range. 1 MB is the only amount of address space that a
MUSYCC function can be assigned.
3
0
RO
MUSYCC memory space is not prefetchable.
2:1
0
RO
MUSYCC can be located anywhere in 32-bit address space.
0
0
RO
This base register is a memory space base register, as opposed
to I/O mapped.
31:20
Name
MUSYCC - Function 0
Base Address Register
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
Register 5–14, Address
14h–38h
Table 2-8. Registers 5–14, Addresses 14h–38h
Bit
Field
31:0
2-12
Name
Reserved
Reset
Value
Type
0
RO
Description
Unused.
Conexant
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Register 15, Address 3Ch
Table 2-9. Register 15, Address 3Ch
Bit
Field
Name
Reset
Value
Type
Description
0Fh
RO
Specifies how quickly MUSYCC needs to gain access to the PCI
bus. The value is specified in 0.25 µs increments and assumes a
33 MHz clock. 0Fh means MUSYCC needs to gain access to the
PCI bus every 130 PCI clock cycles, expressed as 3.75 µs in this
register for 33 MHz PCI and 1.87 µs for 66 MHz PCI.
0
RO
This value specifies, in 0.25 µs increments, the minimum burst
period MUSYCC needs. MUSYCC does not have any special
MIN_GNT requirements. In general, the more channels MUSYCC
has active, the worse the bus latency and the shorter the burst
cycle.
31:24
Maximum Latency
23:16
Minimum Grant
15:8
Interrupt Pin
01b
RO
Defines which PCI interrupt pin Function 0 uses. 01h means
MUSYCC uses pin INTA* for HDLC controller interrupts.
7:0
Interrupt Line
0
RW
Communicates interrupt line routing. System initialization
software will write a value to this register indicating which host
interrupt controller input is connected to MUSYCC’s INTA* pin.
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
2.2.2 Function 1 Expansion Bus Bridge, PCI Slave
MUSYCC, a multifunction PCI device, provides the necessary configuration
space allowing a PCI bus or system controller to query and configure the host
interface of MUSYCC as a PCI device. PCI configuration space consists of a
device-independent header region (64 bytes) and a device-dependent header
region (192 bytes). MUSYCC provides the 64-byte device-independent header
section only. Access to the device-dependent header region results in 0s being
read, and no effect on writes.
There are three types of registers available in MUSYCC:
Read-Only (RO)—Returns a fixed bit pattern if the register is used, or a 0
if the register is unused or reserved.
2. Read-Resettable (RR)—Can be reset to 0 by writing a 1 to the register.
3. Read/Write (RW)—Retains the value last written to it.
1.
MUSYCC’s Function 1 Configuration Space has 16 dword registers.
Tables 2-10 through 2-16 describe these registers.
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2.2 PCI Configuration Registers
Register 0, Address 00h
Table 2-10. Register 0, Address 00h
Bit
Field
Name
Reset
Value
Type
Description
31:16
Device ID(1)
847xh
RO
This unique device identification is assigned by the
manufacturer. This field always returns the value 847xh where x
can be 1, 2, 4, or 8 depending on the 32, 64, 128, or 256 channel
version of the device, respectively.
15:0
Vendor ID(1)
14F1h
RO
The unique vendor identification assigned to the manufacturer.
This field always returns the value 14F1h.
NOTE(S):
(1)
Registers shared between Function 0 and 1.
Register 1, Address 04h
The Status register records status information for PCI bus-related events. The
Command register provides coarse control to generate and respond to PCI
commands.
At reset, MUSYCC sets the bits in this register to 0. This means MUSYCC is
logically disconnected from the PCI bus for all cycle types except configuration
read and configuration write cycles.
Table 2-11. Register 1, Address 04h (1 of 2)
Bit
Field
Reset
Value
Type
0
RR
Detected parity error. This bit is set by MUSYCC whenever it
detects a parity error on a data phase.
30
0
RO
Unused.
29
0
RO
Unused.
28
0
RO
Unused.
27
0
RO
Unused.
26:25
01b
RO
DEVSEL* timing. Indicates MUSYCC is a medium-speed device.
This means the longest time it will take MUSYCC to return
DEVSEL* when the EBUS is the target is 3 clock cycles.
24
0
RO
Unused.
23
01b
RO
Fast back-to-back capable. Indicates that when the EBUS is a
target, it is capable of accepting fast back-to-back transactions
when the transactions are not to the same agent.
22
0
RO
Unused.
21
01b
RO
Indicates the device is 66 MHz capable. This bit is set by
Revision C and later devices.
20:16
0
RO
Unused.
31
2-14
Name
Status
Description
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Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
Table 2-11. Register 1, Address 04h (2 of 2)
Bit
Field
Reset
Value
Type
0
RO
Unused.
6
0
RW
Parity error response.
This bit controls MUSYCC’s Function 1 response to parity
errors.
If 1, MUSYCC will take normal action when a parity error is
detected on a cycle with Function 1 as the target.
If 0, MUSYCC will ignore parity errors.
5:2
0
RO
Unused.
1
0
RW
Memory Space access control.
If 1, enables MUSYCC to respond to Function 1 memory
space access cycles.
If 0, disables MUSYCC’s response.
0
0
RO
I/O space accesses. MUSYCC does not contain any I/O space
registers.
15:7
Name
Command
Description
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
Register 2, Address 08h
This location contains the Class Code and Revision ID registers. The Class Code
register contains the Base Class Code, Sub-Class Code, and Register Level
Programming Interface fields, used to specify the generic functions of MUSYCC.
The Revision ID register denotes the version of silicon.
Table 2-12. Register 2, Address 08h
Bit
Field
Name
31:24
23:16
Class Code
15:8
7:0
Revision ID(1)
Reset
Value
Type
06h
RO
Base Class Code: Bridge Device.
80h
RO
Sub-Class Code Type: Other Bridge Device.
0
RO
Register Level Programming Interface: Indicates there is nothing
special about programming MUSYCC.
01h
RO
Denotes the revision number of MUSYCC. Rev A = 0Ah,
Rev B = 0Bh, Rev C = 0Ch, etc.
Description
NOTE(S):
(1)
Registers shared between Function 0 and 1.
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2.2 PCI Configuration Registers
Register 3, Address 0Ch
Table 2-13. Register 3, Address 0Ch
Bit
Field
Name
31:24
Reserved
23:16
Header Type
15:0
Reserved
Reset
Value
Type
0
RO
Unused.
80h
RO
MUSYCC is a multifunction device with the standard layout of
configuration register space.
0
RO
Unused.
Description
Register 4, Address 10h
Table 2-14. Register 4, Address 10h
Bit
Field
Reset
Value
Type
Description
0
RW
Allows for 1 MB bounded PCI bus address space to be blocked
off as MUSYCC expansion bus space. MUSYCC responds as a
PCI slave with DEVSEL* to all memory cycles whose non-zero
address bits 31:20 match the value of bits 31:20 of this register,
with memory space enabled in Function 1 Register 1, memory
space bit field.
Reads to addresses within this space that are not
implemented. Reads back 0; writes have no effect.
PCI cycles to this space will be mapped to read or write
cycles on the expansion bus.
19:4
0
RO
When appended to bits 31:20, specifies a 1 MB bound memory
space. 1 MB is the only size of address space that a MUSYCC
function can be assigned.
3
0
RO
Expansion bus memory space is not prefetchable.
2:1
0
RO
Means MUSYCC expansion bus space can be located anywhere
in 32-bit address space.
0
0
RO
Means this base register is a memory space base register, as
opposed to I/O mapped.
31:20
Name
EBUS—Function 1
Base Address Register
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
Register 5–14,
Addresses 14h–38h
Table 2-15. Registers 5 through 14–Addresses 14h through 38h
Bit
Field
31:0
2-16
Name
Reserved
Reset
Value
Type
0
RO
Description
Unused.
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2.2 PCI Configuration Registers
Register 15, Address 3Ch
Table 2-16. Register 15, Address 3Ch
Bit
Field
Reset
Value
Name
31:16
Reserved
15:8
7:0
Type
Description
0
RO
Unused.
Interrupt Pin
02h
RO
Defines which PCI interrupt pin Function 1 uses. 02h means
MUSYCC uses pin INTB* for interrupts sourced by devices
connected to EBUS.
Interrupt Line
0
RW
Communicates interrupt line routing. System initialization
software writes a value to this register indicating which host
interrupt controller input is connected to MUSYCC’s INTB* pin.
NOTE(S): An active-low signal is denoted by a trailing asterisk (*).
2.2.3 PCI Reset
MUSYCC resets all internal functions when it detects the assertion of the PRST*
signal line. Upon reset, the following occurs:
•
•
•
•
•
•
All PCI output signals go to three-state immediately and asynchronously
with respect to the PCI clock input, PCLK.
All EBUS output signals go to three-state immediately and asynchronously
with respect to the EBUS clock output, ECLK.
All writable register bits are set to 0.
All PCI data transfers terminate immediately.
All serial data transfers terminate immediately.
MUSYCC disables and responds only to PCI configuration cycles.
2.2.4 Host Interface
After a hardware reset, the PCI configuration space within MUSYCC needs to be
configured by the host with the following information:
For Function 0:
•
•
•
•
•
•
Base address register
Fast back-to-back enable/disable
SERR* signal driver enable/disable
Parity error response enable/disable
Bus mastering enable/disable
Memory space access enable/disable
For Function 1:
•
•
•
Base address register
Parity error response enable/disable
Memory space access enable/disable
Function 0 provides services to the serial interfaces in MUSYCC; Function 1
provides services to the EBUS interface in MUSYCC.
After the configuration spaces are configured, MUSYCC can master the PCI
bus or provide slave-mode access to the host.
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2.2 PCI Configuration Registers
2.2.5 PCI Bus Parity
The agent driving the AD[31:0] signals during any bus phase must also drive the
even parity signal (PAR). PAR is driven one clock after AD[31:0] has been driven
as follows:
•
•
•
Address phase: master always drives PAR one clock after address phase.
Read data phase: target always drives PAR one clock after read data phase.
Write data phase: master always drives PAR one clock after write data
phase.
PAR provides even parity across the AD[31:0] and CBE[3:0]* signal lines.
The agent receiving the data must assert PERR* if it detects a parity error,
provided its Parity Error Response enable bit is set.
If a parity error occurs, the master that generated the cycle (whether it asserted
PERR* or detected it) reports parity errors to the host. MUSYCC does this by
generating an Interrupt Descriptor. It also sets the Data Parity Detected bit (for
masters only) in the Status register in the appropriate function’s PCI configuration
space and sets the Detected Parity Error (for masters or targets) in the same
register if MUSYCC is the agent that detected the error.
PERR* reports errors on the data phases. MUSYCC not only asserts PERR*
when appropriate, but monitors PERR* for its own memory transactions and
notifies the host of the parity error.
SERR* reports parity errors on the address phases. It is assumed that this open
drain PCI signal is tied directly to the host’s system error pin. MUSYCC does not
generate an Interrupt Descriptor if it detects a parity error on an address phase,
nor does it respond to SERR* assertion.
2.2.6 PCI Throughput and Latency Considerations
In PCI systems, achieving high bus throughput works against achieving low bus
latency. As devices burst more data, they keep the bus longer, causing other
devices waiting for the bus to experience a longer acquisition latency as a result.
A PCI bus master introduces latency each time it uses the PCI bus to perform
a transaction. The bus master latency is a function of the following:
2-18
•
Behavior of the master
– State of the GNT* signal
– Bus command used (read, write,...)
– Burst length
– Master data latency for each data phase
– Value of Latency Timer
•
Behavior of the target
– Bus command used (read, write,...)
– Target latency
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2.2 PCI Configuration Registers
When MUSYCC requests the PCI bus, it needs the bus to transfer data
between an internal FIFO buffer and shared memory across the PCI bus with
either a read or a write access. While MUSYCC waits for the bus to be granted,
and then while MUSYCC transfers the data, another equal-sized internal FIFO
buffer is simultaneously being filled or emptied at the serial interface. When
MUSYCC requests the bus, it has data to transfer, and also has a finite amount of
time (which is directly related to the speed of the serial line clock) before a
separate FIFO buffer at the serial interface overflows or underflows.
For an application with many logical channels, MUSYCC requires a new
access cycle on the PCI bus more frequently than an application with fewer
logical channels. If FIFO buffer space is evenly distributed across all channels,
more channels result in less FIFO buffer space per channel, and FIFO buffer
space must be cleared more frequently.
Conversely, an application with high data rate serial interfaces requires a new
access cycle on the PCI bus more frequently than an application with a low data
rate serial interface, because the FIFO buffer fills faster in the former.
Acquiring the PCI bus requires having to deal with arbitration latency, which
is defined as the number of PCI clock cycles a master must wait after asserting its
REQ* and before asserting the GNT* signal. This number is a function of the
system’s arbitration algorithm and takes into account the sequence in which
masters are given access to the bus and the latency timer of each master.
Arbitration latency is also affected by the loading of the system and how
efficiently the bus is being utilized.
The master’s latency timer specifies the maximum number of PCI clock cycles
that the master can (and in the case of MUSYCC, will) keep the bus after starting
the access cycle by asserting its FRAME*. The latency timer also ensures that the
master has a minimum time slot for it to own the bus, but places an upper limit on
how long it will own the bus. In MUSYCC, the Latency Timer is reset to 0 on
PRST* (PCI reset).
Once the bus is acquired and bursting begins, PCI throughput becomes the
point of focus. MUSYCC is capable of multi-dword bursts (read or write). As
each FIFO buffer for a logical channel and direction is serviced on the PCI,
MUSYCC relinquishes and then reacquires the bus to service the FIFO buffer of
the next logical channel. If more logical channels are serviced, bus turnover is
increased, which decreases throughput (but does not necessarily affect service). If
fewer logical channels are serviced, bus turnover decreases, and that increases
throughput (but not necessarily to the benefit of channel processing).
Refer to Chapter 3 of the PCI Local Bus Specification, Revision 2.1, for a
description of bandwidth and latency considerations.
2.2.6.1 PCI Bus Latency
The latency that a PCI master encounters as it tries to gain access to the PCI bus
has three components:
Arbitration latency: usually 2 clock cycles for a high priority device, but is
added into the total latency time only if the bus is idle when a device
requests it, otherwise, it overlaps with the bus acquisition latency.
2. Bus acquisition latency: length of time a device must wait for the bus to
become free.
3. Target latency: length of time the selected target takes to assert TRDY* for
the first data transfer.
1.
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2.2 PCI Configuration Registers
The longest latency MUSYCC experiences in gaining access to the PCI bus is
k–1
LatencyTotal =
å ( Ti + 8 )
i=0
or [k x (T + 8)] when all Tis are equal, where:
k = the number of PCI masters in the system
T = the value of the latency timers in those masters
8 = the longest target latency allowed, in clock cycles (exception: the first data
phase is allowed 16 clock cycles)
Once a master gets the bus, it starts a count-down timer loaded with the
value T, from the latency timer register. When the count reaches 0, the master
relinquishes the bus when its GNT* is removed and it sees TRDY* on the final
data phase. As long as its GNT* is still asserted, the master is free to burst
indefinitely. Table 2-17 provides an example of PCI latency.
Table 2-17. PCI Latency Example
PCI Clock Increment
Bus Activity
0
Bus is idle.
Host asserts REQ*.
MUSYCC asserts REQ*.
+1
Host gets GNT*.
+1
Host asserts FRAME* to start access cycle.
These 2 clock cycles are the arbitration latency
that becomes 0 if the bus was not idle.
+(T + 8) or [16 + (n - 1) x 8] This is the bus acquisition latency time—the amount of time the next requestor must wait for the
whichever is smaller
bus because of current master, the host.
During this time, assume the host loses its GNT* just +1 clock cycle into its acquisition and
— Host has bus —
MUSYCC0 receives the GNT* +1 into this time.
The host’s first data phase must finish within 16 PCI clock cycles, and subsequent data phases
must finish within 8 cycles each. Therefore, 16 + (n - 1) x 8 clock cycles is how long the host will
need the bus to execute n data phases (n dword burst), assuming the host’s access finishes before
its latency timer expires.
As the cycle finishes, the host relinquishes the bus, and one clock cycle later, MUSYCC0 gets
the GNT* and subsequently asserts its FRAME* to start the access cycle.
+(T + 8) or [16 + (n - 1) x 8] MUSYCC0 finishes with the bus, and MUSYCC1 has it on the next clock cycle. During this time,
whichever is smaller
MUSYCC0 loses its GNT*, and MUSYCC1 receives its GNT*. MUSYCC0 behaves similarly to the
host above.
— MUSYCC0 has bus —
+(T + 8) or [16 + (n - 1) x 8]
whichever is smaller
— MUSYCC1 has bus —
MUSYCC1 finishes with the bus, and MUSYCC2 has it on the next clock cycle. During this time,
MUSYCC1 loses its GNT*, and MUSYCC2 receives its GNT*. MUSYCC1 behaves similarly to the
host above.
NOTE(S): An active low signal is denoted by a trailing asterisk (*).
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
The predictable worst case time MUSYCC must wait for the bus in a system
with k masters with equal latency timers is [k x (T + 8)].
If one MUSYCC is configured with all 256 channels active, and receiving and
transmitting at 64 kbps, it must maintain a data rate of 16 Mbps across the PCI
bus. Therefore:
•
256 channels x (64 kbps Rx + 64 kbps Tx) = 32,768 kbps
With 32 bits in each dword, the data rate in kilo dwords per second (kdwps) is:
•
32,768 kbps / (32 bits/dword) = 1,024 kdwps
The 16-clock rule (PCI Local Bus Specification, Revision 2.1) requires that a
single access device must complete the access cycle within 16 clock cycles of the
FRAME* signal being asserted. For devices capable of burst-mode, the 16-clock
rule applies to the completion of the first data cycle.
2.2.6.2 Latency
Computation—Single
Dword Access
Assuming the worst case scenario where the system allows only single dword
access, even a burst-mode device such as MUSYCC must relinquish the PCI bus
within 16 clock cycles from receiving the bus. Using this scenario, the
calculations continue as follows:
•
•
•
•
•
The time per dword would be:
1 dword / 1,024 kdwps = 0.98 µs per dword
Assuming a PCI bus rate of 33 MHz, the time per clock cycle would be:
1 cycle / 33 MHz = 30.303 ns per clock cycle
Assuming a PCI bus rate of 66 MHz, the time per clock cycle would be:
1 cycle / 66 MHz = 15.152 ns per clock cycle
To get the number of clock cycles per dword:
0.98 µs per dword / 0.0303 µs per clock cycle = 33 PCI clock cycles per
dword
To get the number of clock cycles per dword:
0.98 µs per dword / 0.0152 µs per clock cycle = 66 PCI clock cycles per
dword
With one MUSYCC and one host, the host can use the following:
•
•
Assuming a PCI bus rate of 33 MHz:
33 cycles per dword – 16 cycles (16 clock rule) = 17 clock cycles between
dword transfers
Assuming a PCI bus rate of 66 MHz:
66 cycles per dword – 16 cycles (16 clock rule) = 50 clock cycles between
dword transfers
Accordingly, MUSYCC's T must be:
•
•
100660E
Assuming a PCI bus rate of 33 MHz:
17 cycles – 8 cycle (target latency) = 9 clock cycles. As T has a granularity
of 8 units, T must be programmed to 8 PCI clock cycles.
Assuming a PCI bus rate of 66 MHz:
50 cycles – 8 cycle (target latency) = 42 clock cycles. As T has a
granularity of 8 units, T must be programmed to 40 PCI clock cycles.
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2.0 Host Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
2.2 PCI Configuration Registers
2.2.6.3 Latency
Computation—Burst
Access
When the following is assumed:
•
•
•
•
MUSYCC has enough internal buffering to buffer up to 4-dwords worth of
information per channel before performing a 2-dword burst cycle for every
access.
MUSYCC has a granularity of 8 for its latency timer (that is, MUSYCC is
always configured to give up the bus in equal to or less than the desired
time-out).
The system will support MUSYCC burst writes and reads.
MUSYCC, with all 256 receive and transmit channels active, needs to
move 1,024 kdwords/s, or one dword every 0.98 µs, or 4-dword bursts
every 3.92 µs. That is, 130 clock cycles between bursts for a 33-MHz PCI
bus rate, and 260 clock cycles for a 66-MHz PCI bus rate.
The following can be seen:
•
•
•
•
•
The worst case time it would take each burst cycle to finish is 16 cycles (16
clock rule) + 8 cycles, target latency = 24 clock cycles to finish, worst
case.
With one MUSYCC and one host operating at a PCI bus rate of 33 MHz:
The host has 130 cycles between bursts – 24 cycles to finish, worst case =
106 clock cycles. The host's T must be programmed to 106 cycles –
8 cycles, target latency = 98 cycles. Rounding for granularity yields
96 cycles.
With one MUSYCC and one host operating at a PCI bus rate of 66 MHz:
The host has 260 cycles between bursts – 24 cycles to finish, worst case =
236 clock cycles. The host's T must be programmed to 236 cycles –
8 cycles, target latency = 228 cycles. Rounding for granularity yields
224 cycles.
For n MUSYCC and one host operating at a PCI bus rate of 33 MHz:
The host has 130 cycles between bursts – (n x 24 cycles, worst case) –
8 clock cycles, target latency = T cycles. Therefore, for two MUSYCC's
and one host, a host's T of 24 would be sufficient; that is, 130 cycles –
(2 x 24) – 8 cycles = 74 clock cycles. Rounding for granularity equals
72 cycles.
For n MUSYCC and one host operating at a PCI bus rate of 66 MHz:
The host has 260 cycles between bursts – (n x 24 cycles, worst case) –
8 clock cycles, target latency = T cycles. Therefore, for two MUSYCC's
and one host, a host's T of 24 would be sufficient; that is, 260 cycles –
(2 x 24) – 8 cycles = 204 clock cycles. Rounding for granularity equals
200 cycles.
On reset, the value of the latency timers are reset to 0.
2-22
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3
3.0 Expansion Bus (EBUS)
MUSYCC provides a PCI bridge to a local bus interface on MUSYCC called the
Expansion Bus (EBUS). The EBUS provides a host processor across the PCI bus
to access up to 1 MB of peripheral memory space on the EBUS.
Although EBUS utilization is optional, the most notable application for the
EBUS is the connection to peripheral devices (e.g., Bt8370 T1/E1 framers) local
to MUSYCC’s serial port. Figures 3-1 and 3-2 illustrate block diagrams of the
EBUS interface with and without local Multiprocessor Unit (MPU).
Figure 3-1. EBUS Functional Block Diagram with Local MPU
Local
Expansion
Bus
EBUS
Interface
Clock
Regenerated
and
Inverted
Address/Data
Clock
Address/Data
MPU
Intel
Motorola
Control
Bus
Arbiter
Interrupt
Bus Arbitration
EINT*
T1/E1
Framer
Bt8370
8478_007
Figure 3-2. EBUS Functional Block Diagram without Local MPU
Clock
Address/Data
EBUS
Interface
Control
Local RAM
Downloadable
ROM
EINT*
Peripheral
Devices
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
3.1 Operation
3.1.1 Initialization
At initialization, MUSYCC’s PCI Function 1 Configuration Space is initialized
with a value representing a 1 MB memory range assigned to MUSYCC’s EBUS.
This is detailed in Table 2-14, Register 4, Address 10h, and listed as
EBUS—Function 1 Base Address Register. An unmapped 1 MB system memory
range must be specified by assigning the upper 12 bits of the memory range to the
upper 12 bits of this register.
Command bit field memory space access control and optional parity error
response must be properly configured for MUSYCC to respond to EBUS
memory space accesses (see Table 2-4, Register 1, Address 04h).
On reset, MUSYCC disables EBUS memory space access. If the PCI attempts
to access EBUS memory space, there will be a PCI master-abort termination.
3.1.2 Address and Data
When MUSYCC’s host interface claims the cycle during a PCI access cycle, the
host interface compares the upper 12 bits of the PCI address lines to each of its
function’s base address registers. If signal lines AD[31:20] are identical to the
upper 12 bits of the Expansion Bus Base Address register, MUSYCC forwards
the access cycle to the EBUS interface within MUSYCC.
NOTE:
Only single dword PCI operations can be performed when accessing the
EBUS.
MUYSCC accepts PCI slave burst write cycles to either function 0 or
function 1.
MUSYCC’s host interface has an internal 4-dword write FIFO buffer shared
by both functions; therefore a 1–4 dword burst write cycle can be performed to
either function. When the burst write data phase exceeds the length, MUSYCC
asserts a PCI target disconnect.
MUSYCC performs a PCI target disconnect after the first data phase of any
burst read cycle to either Function 0 or Function 1. Therefore, the PCI bridge
must be able to fragment a burst access into a single phase read or 1–4 phase burst
writes as controlled by the target disconnect.
Assuming the EBUS is connected to byte-wide peripheral devices, the EBUS
interface uses the lower 20 bits from PCI address lines AD[19:0] to construct a
byte address for the EBUS. Specifically, PCI address lines AD[19:2] are
converted to EBUS address lines EAD[17:0] by shifting out the two least
significant bits, AD[1:0]. This allows for byte-level addressing for up to 4
byte-wide devices on the EBUS. Given the above, the EBUS provides an 18-bit
addressing structure allowing byte addressing of up to four banks of 256 kB
address space each.
3-2
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
The EBUS interface transfers 32 bits of the data lines between the EBUS and
the PCI bus. The byte-enable signal lines EBE[3:0]* are transferred from the PCI
byte-enable signal lines CBE[3:0]* to the EBUS, and indicate which byte(s) in the
data dword are valid. Figure 3-3 illustrates both data and data configurations of
the 32-bit word.
Figure 3-3. EBUS Address/Data Line Structure
Address Lines–EAD[31:0] During Address Phase
31
20 19 17
00 YYYYYYYYYYYYYYYYYY
00000000000000
Upper 12 Bits
always 0 during
address phase
0 Bit Number
Lower 20 Bits
AD[19:2] transferred from PCI Bus
to EAD[17:0] on the EBUS.
Byte addressing with bits 19 and 18
always 0 during address phase.
Data Lines–EAD[31:0] During Data Phase
31
YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
0 Bit Number
All 32 bits transferred between PCI bus and EBUS.
The byte enable lines indicate which bits are valid in
the 32-bit dword during the data phase.
8478_009
NOTE(S):
1.
2.
3.
4.
5.
Byte Enable 0–EBE[0]* signals if EAD[7:0] are valid data bits during data phase.
Byte Enable 1–EBE[1]* signals if EAD[15:8] are valid data bits during data phase.
Byte Enable 2–EBE[2]* signals if EAD[23:16] are valid data bits during data phase.
Byte Enable 3–EBE[3]* signals if EAD[31:24] are valid data bits during data phase.
An active low signal is denoted by a trailing asterisk (*).
3.1.3 Clock
The ECLK is derived from the PCI clock and runs at up to a 33 MHz clock rate.
This operation is controlled by the M66EN input on Revision C and later devices.
An asserted M66EN input implies that the overall system is operating at a 66
MHz PCI clock rate; the ECLK is running at half of the PCI clock rate.
Otherwise, the ELCK is operating at the same rate as the PCI clock frequency. In
order to ensure that the ELCK is properly operational, the M66EN input state
shall not be changed during the whole operational period.
The EBUS clock output can be disabled by setting the ECKEN bit field (see
Table 5-6). In the disabled state, the ECLK output is three-stated.
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
3.1.4 Interrupt
When a device connected to the EBUS drives the EINT* signal, MUSYCC
carries this signal through to the PCI interrupt line, INTB*. Thus, peripheral
devices can interrupt the host processor.
In MUSYCC’s Function 1 PCI Configuration Space (the EBUS function), the
Interrupt Pin bit field indicates that the INTB* PCI interrupt be asserted for
interrupts sourced by devices connected to the EBUS (see Table 2-16, Register
15, Address 3Ch). Also, the Interrupt Line bit field in the same register is set up
by the system initialization software to indicate which host interrupt controller
input pin is to be connected to MUSYCC’s INTB* pin.
3.1.5 Address Duration
MUSYCC can extend the duration the address bits are valid for any EBUS
address phase by specifying a value from 0–3 in ALAPSE bit field (refer to
Table 5-6, Global Configuration Descriptor). The value specifies the additional
ECLK periods the address bits remain asserted. That is, a value of 0 specifies the
address remains asserted for one ECLK period, and a value of 3 specifies the
address remains asserted for four ECLK periods. Disabling the ECLK signal
output does not affect the delay mechanism. Refer to the timing diagrams in
Section 7.2.4 for more details.
Both pre- and post-address cycles are always present during the address phase
of an EBUS cycle. The post-address cycle is one PCI period long and provides
MUSYCC time to transition between the address phase and the following data
phase. The pre- and post-address cycles are not included in the address duration.
3.1.6 Data Duration
MUSYCC can extend the duration that the data bits are valid for any EBUS data
phase by specifying a value from 0–7 in ELAPSE bit field (refer to
Table 5-6, Global Configuration Descriptor). The value specifies the additional
ECLK periods the data bits remain asserted. That is, a value of 0 specifies the
data that remains asserted for one ECLK period, and a value of 7 specifies the
data that remains asserted for eight ECLK periods. Disabling the ECLK signal
output does not affect the delay mechanism. Refer to the timing diagrams in
Section 7.2.4 for more details.
A pre-data and post-data cycle are always present during the data phase of an
EBUS cycle. The pre-data cycle is one PCI period long and provides MUSYCC
setup and hold time for the data signals. The post-data cycle is one ECLK period
long and provides MUSYCC time to transition between the data phase and the
following bus cycle termination. The pre- and post-data cycles are not included in
the data duration.
3-4
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
3.1.7 Bus Access Interval
MUSYCC can be configured to wait a specified amount of time after it releases
the EBUS and before it requests the EBUS a subsequent time. This is
accomplished by specifying a value 0–7 in BLAPSE bit field (refer to
Table 5-6, Global Configuration Descriptor). The value specifies the additional
ECLK periods MUSYCC waits immediately after releasing the bus; that is, a
value of 0 specifies MUSYCC will wait for one ECLK period, and a value of 5
specifies six ECLK periods. Disabling the ECLK signal output does not affect
this wait mechanism. Refer to the timing diagrams in Section 7.2.4 for more
details.
The bus grant signal (HLDA/BG*) is deasserted by the bus arbiter only after
the bus request signal (HOLD/BR*) is deasserted by MUSYCC. As the amount
of time between bus request deassertion and bus grant deassertion can vary from
system to system, it is possible for a misinterpretation of the “old” bus grant
signal as an approval to access the EBUS. MUSYCC provides the flexibility
through the bus access interval feature to wait a specific number of ECLK periods
between subsequent bus requests. (Refer to EBUS arbitration timing diagrams,
Figure 7-13, EBUS Write/Read Transactions, Intel-Style and Figure 7-14, EBUS
Write/Read Transactions, Motorola-Style.)
3.1.8 PCI to EBUS Interaction
Using the EBUS to perform extensive polling of peripheral devices substantially
increases PCI bus utilization. The EBUS interface within MUSYCC performs
single dword access without burst cycles. Also, the access time for data on the
EBUS is dependent on how fast the peripherals respond to an EBUS read or write
cycle.
PCI write access cycles targeted at the EBUS are not at issue because they
complete immediately. MUSYCC’s host interface autonomously completes
writing data to the EBUS after successfully terminating the host’s PCI write
access cycle.
PCI read access cycles targeted at the EBUS are at issue because they cause
MUSYCC’s host interface to first claim the access cycle, then immediately
initiate a PCI Target Retry sequence. This causes the PCI bridge device to retry
the same EBUS access at a later time. Concurrently, the EBUS interface is
activated to access the requested data from the EBUS. Because this process may
take many EBUS clock cycles to complete, the host interface is capable of
holding off each retry request by initiating a subsequent Target Retry sequence
until the EBUS interface delivers the required data to the host interface. Target
Retry sequences may occur multiple times.
As EBUS data is made available to the host interface, and on the next retry
from the bridge chip, the host interface checks whether or not the retry cycle
address matches the address latched in during the initial EBUS access cycle and,
if so, forwards the EBUS data to the requester. If the addresses do not match,
MUSYCC starts a new EBUS access cycle.
The amount of time to complete a single EBUS cycle accessing a single dword
at a time and the number of bus turnovers between successive retries affect PCI
bus utilization. To avoid affecting the PCI bus adversely, systems must be
designed to throttle EBUS access or use a local microprocessor on the EBUS to
filter the information from peripheral devices.
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Conexant
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
3.1.9 Microprocessor Interface
The MPUSEL bit field specifies the type of microprocessor interface to use for
the EBUS. (See Table 5-6, Global Configuration Descriptor.)
Table 3-1 describes the effective signals when Intel-style protocol is selected.
Table 3-1. Intel Protocol Signals
Signal
Description
Interpretation
ALE*
Address Latch Enable
Asserted low by MUSYCC to indicate that the
address lines contain a valid address. This signal
remains asserted for the duration of the access
cycle.
RD*
Read
Strobed low by MUSYCC to enable data reads out of
the device. Held high during writes.
WR*
Write
Strobed low by MUSYCC to enable data writes into
the device. Held high during reads.
HOLD
Hold Request
Asserted high by MUSYCC when it requests the
EBUS from a bus arbiter.
HLDA
Hold Acknowledge
Asserted high by bus arbiter in response to HOLD
signal assertion. Remains asserted until after the
HOLD signal is deasserted. If the EBUS is connected
and there are no bus arbiters on the EBUS, this
signal must be asserted high at all times.
NOTE(S): An active low signal is denoted by a trailing asterisk (*).
3-6
Conexant
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
Table 3-2 shows the effective signals when Motorola-style protocol is
selected.
Table 3-2. Motorola Protocol Signal
Signal
Description
Interpretation
AS*
Address Strobe
Driven low by MUSYCC to indicate that the address
lines contain a valid address. This signal remains
asserted for the duration of the access cycle.
DS*
Data Strobe
Strobed low by MUSYCC to enable data reads or data
writes for the addressed device.
R/WR*
Read/Write
Held high throughout read operation and held low
throughout write operation by MUSYCC. This signal
determines the meaning (read or write) of DS*.
BR*
Bus Request
Asserted low by MUSYCC when it requests the EBUS
from a bus arbiter.
BG*
Bus Grant
Asserted low by bus arbiter in response to BR* signal
assertion. Remains asserted until after the BR* signal
is deasserted. If the EBUS is connected and there are
no bus arbiters on the EBUS, this signal must be
asserted low at all times.
BGACK*
Bus Grant
Acknowledge
Asserted low by MUSYCC when it detects BGACK*
currently deasserted. As this signal is asserted,
MUSYCC begins the EBUS access cycle. After the
cycle is finished, this signal is deasserted indicating to
the bus arbiter that MUSYCC has released the EBUS.
NOTE(S): An active low signal is denoted by a trailing asterisk (*).
3.1.10 Arbitration
The HOLD and HLDA (Intel style) or BR* and BG* (Motorola style) signal lines
are used by MUSYCC to arbitrate for the EBUS.
For Intel-style interfaces, the arbitration protocol is as follows (refer to
Figure 7-13, EBUS Write/Read Transactions, Intel-Style):
1.
2.
3.
4.
5.
6.
7.
8.
9.
100660E
MUSYCC three-states EAD[31:0], EBE*[3:0]. WR*, RD*, and ALE*.
MUSYCC requires EBUS access and asserts HOLD.
MUSYCC checks for HLDA assertion by bus arbiter.
If HLDA is deasserted, MUSYCC waits for the HLDA signal to become
asserted before continuing the EBUS operation.
If HLDA is asserted, MUSYCC continues with the EBUS access because
it has control of the EBUS.
MUSYCC drives EAD[31:0], EBE*[3:0], WR*, RD*, and ALE*.
MUSYCC completes EBUS access and deasserts HOLD.
Bus arbiter deasserts HLDA shortly thereafter.
MUSYCC three-states EAD[31:0], EBE*[3:0]. WR*, RD*, and ALE*.
Conexant
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
For Motorola-style interfaces, the arbitration protocol is as follows (refer to
Figure 7-14, EBUS Write/Read Transactions, Motorola-Style):
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
MUSYCC three-states EAD[31:0], EBE*[3:0]. R/WR*, DS*, and AS*.
MUSYCC requires EBUS access and asserts BR*.
MUSYCC checks for BG* assertion by bus arbiter.
If BG* is deasserted, MUSYCC waits for the BG* signal to become
asserted before continuing the EBUS operation.
If BG* is asserted, MUSYCC continues with the EBUS access as it has
control of the EBUS.
If BGACK* is deasserted, MUSYCC assumes control of the EBUS by
asserting BGACK*.
MUSYCC drives EAD[31:0], EBE*[3:0], R/WR*, DS*, AS*.
Shortly after the EBUS cycle is started, MUSYCC deasserts BR*.
Bus arbiter deasserts BG* shortly thereafter.
MUSYCC completes EBUS cycle.
MUSYCC deasserts BGACK*.
MUSYCC three-states EAD[31:0], EBE*[3:0]. R/WR*, DS*, and AS*.
3.1.11 Connection
Using the EBUS address lines, EAD[17:0], and the byte enable lines, EBE[3:0]*,
the EBUS can be connected in either a multiplexed or non-multiplexed address
and data mode.
Figures 3-4 and 3-5 illustrate two examples of non-multiplexed address and
data modes. These figures illustrate four separate byte-wide framer devices
connected to the EBUS with each byte enable line used as the chip select for
separate devices. This allows a full dword data transfer over the EBUS.
Figure 3-4. EBUS Connection, Non-multiplexed Address/Data, 8 Framers, No MPU
EAD[31:24]
EAD[31:0]
EAD[23:16]
EAD[15:8]
EAD[7:0]
MUSYCC
EAD[8:0]
Data Addr
CN8370
CS*
EINT*
Data Addr
CN8370
CS*
Data Addr
CN8370
CS*
Data Addr
CN8370
CS*
AS*, R/WR*, DS*,
ECLK Control Lines
EBE[3:0]*
EAD9
EBE[0]*
EBE[1]*
dev 0,4
Device 0,4
Device 1,5
Device 2,6
Device 3,7
Chip
Select
EBE[2]* Logic
EBE[3]*
8478_010
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Conexant
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
Figure 3-5. EBUS Connection, Non-multiplexed Address/Data, 61 Framers, No MPU
EAD[31:24]
EAD[23:16]
EAD[31:0]
EAD[15:8]
EAD[7:0]
EAD[8:0]
EINT*
9
Data Addr
2xCN8370
CS*
EAD[10,9]
Dev 0
Control
Lines
8
9
Data Addr
2xCN8370
CS*
Dev 1
Dev 0, Bank 0
Control
8
9
Data Addr
2xCN8370
CS*
Dev 2
8
9
Data Addr
2xCN8370
CS*
Dev 3
Framer Bank 0
Framer Bank 1
Framer Bank 2
Framer Bank 3
Framer Bank 4
MUSYCC
8
EBE[3:0]
Chip
Select
Logic
Dev 0, Bank 1
Dev 0, Bank 2
Dev 0, Bank 3
Dev 0, Bank 4
8478_011
NOTE(S):
1. EBEx[3:0]* selects device x in each framer block.
2. EAD[31:0], AS* are supplied to each framer block.
3. EBEx*, AS* are supplied to each chip select block.
Figure 3-6 illustrates how additional address lines can be combined with each
byte enable line during the address phase to support multiple framer banks with
each bank containing four byte-wide framer devices.
In the multiplexed address and data mode, four byte-wide peripheral devices
are connected to the EBUS. In this mode, 8 bits of the 32-bit EBUS transfer data
to and from each device individually.
NOTE:
100660E
The multiplexed address and data mode example does not allow for 4-byte
data transfers.
Conexant
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3.0 Expansion Bus (EBUS)
Multichannel Synchronous Communications Controller (MUSYCC™)
3.1 Operation
Figure 3-6. EBUS Connection, Multiplexed Address/Data, 8 Framers, No MPU
EAD[8:0]
Data Addr
2xCN8370
CS*
EINT*
Data Addr
2xCN8370
CS*
Data Addr
2xCN8370
CS*
Data Addr
2xCN8370
CS*
MUSYCC
AS*, RWR*, DS*,
ECLK Control Lines
2:4 Decoder
Y1
EAD[10:9]*
A1
A2
Y2
Y3
Y4
ALE
EBE[0]
8478_012
3-10
Conexant
100660E
4
4.0 Serial Interface
Each serial interface consists of Serial Port Interfaces (SERI), Bit Level
Processors (BLP), Direct Memory Access Controllers (DMAC), and an Interrupt
Controller (INTC). A separate set of SERI, BLP, and DMAC services receive
channels and transmit channels independently. A single INTC is shared by the
receive and transmit BLP. Figure 4-1 illustrates the serial port/host interface.
Figure 4-1. Serial Interface Functional Block Diagram, Channel Group 0
Serial Interface
Channel Group 0
Rx Control
Rx DMAC
Rx
Bit Level
Processor
Rx
Port
Interface
Interrupt
Interrupt
Controller
Tx Data
Tx Control
Tx DMAC
Serial Port
Host Interface
Rx Data
Clock
Synchronization
Data
Out-of-Frame
Status
Rx Event
Tx Event
Tx
Bit Level
Processor
Tx
Port
Interface
Clock
Synchronization
Data
8478_013
NOTE(S):
1.
2.
3.
4.
Channel Groups 1, 2, 3, 4, 5, 6, and 7, when supported, are identical to Group 0.
Bt8478 supports Channel Groups 0 through 7.
Bt8474 supports Channel Groups 0, 1, 2, and 3.
Bt8472 supports Channel Groups 0 and 1.
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4.0 Serial Interface
4.1 Serial Port Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.1 Serial Port Interface
A receive serial port interface (Rx-SERI) connects to four input signals: RCLK,
RDAT, RSYNC, and ROOF. A transmit serial port interface (Tx-SERI) connects
to two input signals and one output signal, TCLK, TSYNC, and TDAT,
respectively (refer to Table 1-4, CN8478 Hardware Signal Definitions). The SERI
is responsible for receiving and transmitting data bits to FIFO buffers in the BLP.
The receive and transmit data and synchronization signals are synchronous to
the receive and transmit line clocks, respectively. MUSYCC can be configured to
sample in and latch out data signals and sample in status and synchronization
signals on either the rising or falling edges of the respective line clock, RCLK and
TCLK. This configuration is accomplished by setting the ROOF_EDGE,
RSYNC_EDGE, RDAT_EDGE, TSYNC_EDGE, and TDAT_EDGE bit fields
(detailed in Table 5-12, Port Configuration Descriptor).
The default, after device reset, is to sample in and latch out data,
synchronization, and status on the falling edges of the respective line clock.
4.2 Bit Level Processor
The bit-level processors (Rx-BLP and Tx-BLP) service the bits in the receive and
transmit path. As internal FIFO buffers are filled and flushed, the BLP requests
memory transfers from the DMAC. The BLP coordinates all bit-level transactions
between SERI and DMAC. The BLP also interacts with the INTC to notify the
host of events and errors during bit-level processing.
4.3 DMA Controller
The DMA controllers (Rx-DMAC and Tx-DMAC) manage all memory
operations between a corresponding BLP and the host interface. DMAC takes
requests from BLP to either fill or flush internal FIFO buffers, sets up an access
to data buffers in shared memory, and requests access to the PCI bus through the
host interface.
4.4 Interrupt Controller
The interrupt controller takes receive and transmit events from Rx-BLP and
Tx-BLP, respectively. The INTC coordinates the transfer of internally queued
descriptors to an interrupt queue in shared memory and also coordinates the
notification to the host of pending interrupts.
4-2
Conexant
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5 Channelized Port Mode
4.5 Channelized Port Mode
Each SERI can be configured independently using the PORTMD bit field
(see Table 5-12, Port Configuration Descriptor).
Channelized mode refers to a data bit stream segmented into frames. Each
frame consists of a series of 8-bit time slots. Typically, each time slot recurs every
125 µs at an 8 kHz rate. MUSYCC maintains frame synchronization in both the
transmit and receive directions by using the TSYNC and RSYNC input signals. In
addition, the ROOF input signal can be used to notify MUSYCC of the loss of
frame synchronization.
Table 4-1 describes the contents of a typical 8 kHz frame in each of the
possible channelized port modes.
Table 4-1. Channelized Serial Port Modes
Mode
Clock
Frequency
Bits per
Frame
T1
1.544 MHz
193
Single frame bit, followed by 24 time slots,
numbered TS0–TS23.
E1
2.048 MHz
256
32 time slots, numbered TS0–TS31.
2 E1
4.096 MHz
512
64 time slots, numbered TS0–TS63.
4 E1
8.192 MHz
1024
128 time slots, numbered TS0–TS127.
Nx128
Nx64 kHz
(1 ≤ N ≤ 128)
Nx8
(1 ≤ N ≤ 128)
Description
N time slots, numbered TS0–TSN-1.
4.5.1 Hyperchannels (Nx64)
A hyperchannel results from assigning bits from one or more 8-bit time slots
within a frame. A hyperchannel can comprise from 1–128 time slots. This results
in one logical channel supporting an Nx64 kbps bit rate where the actual data rate
can range between 64 kbps and 8.192 Mbps. The concatenated time slots need not
be contiguous.
Hyperchanneled time slots assigned to the same logical channel number
within a channel group (0–31) are required for proper support.
The Time Slot Descriptor enables and assigns a time slot to a logical channel
(see Table 5-15, Time Slot Descriptor). The configurations for receive and
transmit hyperchannels are independent.
4.5.2 Subchannels (Nx8)
A subchannel results from treating each bit in an 8-bit time slot independently and
assigning a logical channel number to each active bit. Not all 8 bits need to be
active, and any combination of bits within the 8 in a time slot can be assigned to
the same logical channel number. Similarly, multiple time slots can supply one or
more bits to comprise one subchannel. This results in one logical channel
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Conexant
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5 Channelized Port Mode
supporting an Nx8 bit rate between 8 kbps to 64 kbps in multiples of 8 kbps. The
following configurations are required to support subchannels:
•
•
•
Each active bit is assigned a logical channel number within a channel
group (0–31).
Each time slot with active bits must be enabled in the Time Slot Map.
Each active bit (after the first bit, bit 0) must be enabled in the Subchannel
Map.
The Time Slot Descriptor (Table 5-15), and the Subchannel Descriptor
(Table 5-17), enable and assign a time slot and each individual bit within the time
slot to a logical channel. The configurations for receive and transmit subchannels
are independent.
The Time Slot Descriptor assigns bit 0 of a time slot to a logical channel. The
Subchannel Descriptor assigns bits 1 through 7 of a time slot to a logical channel.
4.5.3 Frame Synchronization Flywheel
MUSYCC utilizes the TSYNC and RSYNC signals to maintain a timebase which
keeps track of the active bit in the current time slot. The mechanism is referred to
as the frame synchronization flywheel. The flywheel counts the number of bits
per frame and automatically rolls over the bit count according to the programmed
mode. The TSYNC or RSYNC input marks the first bit in the frame. The mode
specified in the PORTMD bit field (Table 5-12, Port Configuration Descriptor),
determines the number of bits in the frame. A flywheel exists for both the
transmit and receive functions for every port.
The flywheel is synchronized when MUSYCC detects TSYNC = 1 or
RSYNC = 1, for transmit or receive functions, respectively. Once synchronized,
the flywheel maintains synchronization without further assertion of the
synchronization signal.
A time slot counter within each port is reset at the beginning of each frame
and tracks the current time slot being serviced.
For the Nx64 mode, the value of N cannot be specified; therefore, the data
requires a synchronization pulse every frame period to reset the flywheel. Also, in
Nx64 mode, the TSYNC must precede the output of bit 0 of the frame by four line
clock periods.
Figures 4-2 through 4-4 illustrate the timing relationships between the data
and the synchronization signal for various modes of operation.
4-4
Conexant
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5 Channelized Port Mode
Figure 4-2. Transmit and Receive T1 Mode
RCLK
RSYNC-RISE(a)
RDATA-RISE(a)
6
7
F-bit
0
1
2
3
4
5
6
7
0
RSYNC-RISE(b)
RDAT-FALL(b)
6
7
F-bit
0
1
2
3
4
5
6
7
0
RSYNC-FALL(c)
RDATA-RISE(c)
6
7
F-bit
0
1
2
3
4
5
6
7
0
RSYNC-FALL(d)
RDAT-FALL(d)
6
7
F-bit
0
1
2
3
4
5
6
7
0
6
7
F-bit
0
1
2
3
4
5
6
7
0
TCLK
TSYNC-RISE(a)
TDAT-RISE(a)
TSYNC-RISE(b)
TDATA-FALL(b)
6
7
F-bit
0
1
2
3
4
5
6
7
0
TSYNC-FALL(c)
TDAT-RISE(c)
6
7
F-bit
0
1
2
3
4
5
6
7
0
TSYNC-FALL(d)
TDATA-FALL(d)
6
7
F-bit
0
1
2
3
4
5
6
7
0
8478_014
NOTE(S):
1. T1 Mode employs 24 time slots (0–23) with 8 bits per time slot (0–7) and 1 frame bit every 193 clock periods. One frame
of 193 bits occurs every 125 µs—1.544 MHz.
2. RSYNC and TSYNC must be asserted for a minimum of 1 CLK period.
3. MUSYCC can be configured to sample RSYNC, TSYNC, RDAT, and TDAT on either a rising or falling clock edge
independent of any other signal sampling configuration.
4. Relationships between the various configurations of active edges for the synchronization signal and the data signal are
shown using a common clock signal for receive and transmit operations. Note the relationship between the frame bit
(within RDAT, TDAT) and the frame synchronization signal (e.g., RSYNC, TSYNC).
5. All received signals (e.g., RSYNC, RDAT, TSYNC) are sampled on the specified clock edge (e.g., RCLK, TCLK). All transmit
data signals (TDAT) are latched on the specified clock edge.
6. In configuration (a), synchronization and data signals are sampled or latched on a rising clock edge.
7. In configuration (b), synchronization signal is sampled on a rising clock edge, and the data signal is sampled or latched on
a falling clock edge.
8. In configuration (c), synchronization signal is sampled on a falling clock edge, and the data signal is sampled or latched on
a rising clock edge.
9. In configuration (d), synchronization and data signals are sampled or latched on a falling clock edge.
100660E
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5 Channelized Port Mode
Figure 4-3. Transmit and Receive E1 (also 2xE1, 4xE1) Mode
RCLK
RSYNC-RISE(a)
RDATA-RISE(a)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-RISE(b)
RDAT-FALL(b)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-FALL(c)
RDATA-RISE(c)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-FALL(d)
RDAT-FALL(d)
6
7
0
1
2
3
4
5
6
7
0
1
TCLK
TSYNC-RISE(a)
TDAT-RISE(a)
6
7
0
1
2
3
4
5
6
7
0
1
TSYNC-RISE(b)
TDATA-FALL(b)
6
7
0
1
2
3
4
5
6
7
0
1
TSYNC-FALL(c)
TDAT-RISE(c)
6
7
0
1
2
3
4
5
6
7
0
1
TSYNC-FALL(d)
TDATA-FALL(d)
6
7
0
1
2
3
4
5
6
7
0
1
8478_015
NOTE(S):
1. E1 Mode employs 32 time slots (0–31) with 8 bits per time slot (0–7) and 256 bits per frame and one frame every
125 µs—2.048 MHz.
2. 2xE1 mode employs 64 time slots (0–63) with 8 bits per time slot (0–7) and 512 bits per frame and one frame every
125 µs—4.096 MHz.
3. 4xE1 mode employs 128 time slots (0–127) with 8 bits per time slot (0–7) and 1024 bits per frame and one frame every
125 µs—8.192 MHz.
4. RSYNC and TSYNC must be asserted for a minimum of 1 CLK period.
5. MUSYCC can be configured to sample RSYNC, TSYNC, RDAT, and TDAT on either a rising or falling clock edge
independent of any other signal sampling configuration.
6. Relationships between the various configurations of active edges for the synchronization signal and the data signal are
shown using a common clock signal for receive and transmit operations. Note the relationship between the frame bit
(within RDAT, TDAT) and the frame synchronization signal (e.g., RSYNC, TSYNC).
7. All received signals (e.g., RSYNC, RDAT, TSYNC) are sampled on the specified clock edge (e.g., RCLK, TCLK). All transmit
data signals (TDAT) are latched on the specified clock edge.
8. In configuration (a), synchronization and data signals are sampled or latched on a rising clock edge.
9. In configuration (b), synchronization signal is sampled on a rising clock edge, and the data signal is sampled or latched on
a falling clock edge.
10. In configuration (c), synchronization signal is sampled on a falling clock edge, and the data signal is sampled or latched on
a rising clock edge.
11. In configuration (d), synchronization and data signals are sampled or latched on a falling clock edge.
4-6
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5 Channelized Port Mode
Figure 4-4. Transmit and Receive Nx64 Mode
RCLK
RSYNC-RISE(a)
RDATA-RISE(a)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-RISE(b)
RDAT-FALL(b)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-FALL(c)
RDATA-RISE(c)
6
7
0
1
2
3
4
5
6
7
0
1
RSYNC-FALL(d)
RDAT-FALL(d)
6
7
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
0
1
2
3
4
5
TCLK
TSYNC-RISE(a)
TDAT-RISE(a)
TSYNC-RISE(b)
TDATA-FALL(b)
2
3
4
5
6
7
0
1
2
3
4
5
TSYNC-FALL(c)
TDAT-RISE(c)
2
3
4
5
6
7
0
1
2
3
4
5
TSYNC-FALL(d)
TDATA-FALL(d)
2
3
4
5
6
7
0
1
2
3
4
5
8478_016
NOTE(S):
1. Nx64 Mode employs N time slots with 8 bits (0–7) per time slot.
2. RSYNC and TSYNC must be asserted for a minimum of 1 CLK period.
3. Assertion of TSYNC must precede transmission of bit 0 of a frame by exactly 4 line clock periods due to the internal buffer
scheme used for transmitting of Nx64 mode data bits.
4. RSYNC and TSYNC signals must be provided for every received and transmitted frame in Nx64 mode.
5. If N = 1, the minimum, then 8 bits/frame = 64 kHz. If N = 128, the maximum, then 1024 bits/frame = 8.192 MHz.
6. Relationships between the various configurations of active edges for the synchronization signal and the data signal are
shown using a common clock signal for receive and transmit operations. Note the relationship between the frame bit
(within RDAT, TDAT) and the frame synchronization signal (e.g., RSYNC, TSYNC).
7. All received signals (e.g., RSYNC, RDAT, TSYNC) are sampled on the specified clock edge (e.g., RCLK, TCLK). All transmit
data signals (TDAT) are latched on the specified clock edge.
8. In configuration (a), synchronization and data signals are sampled or latched on a rising clock edge.
9. In configuration (b), synchronization signal is sampled on a rising clock edge, and the data signal is sampled or latched on
a falling clock edge.
10. In configuration (c), synchronization signal is sampled on a falling clock edge, and the data signal is sampled or latched on
a rising clock edge.
11. In configuration (d), synchronization and data signals are sampled or latched on a falling clock edge.
100660E
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4.0 Serial Interface
4.5 Channelized Port Mode
Multichannel Synchronous Communications Controller (MUSYCC™)
4.5.4 Change-of-Frame Alignment
A Change of Frame Alignment (COFA) condition is defined as a frame
synchronization event detected when it is not expected, and includes the detection
of the first occurrence of frame synchronization when none is present.
When the serial interface detects a COFA condition, an internal COFA signal
is asserted for one frame period. During that period, MUSYCC’s channel group
processor terminates all active messages during the channel map processing.
For each receiver channel found to be active and processing a message during
the RCOFA event, each of these channels’ Buffer Status Descriptor is written
with the COFA error encoding. The Buffer Status Descriptor is written if
configured to do so in the Group Configuration Descriptor. MUSYCC then
proceeds to the next Message Descriptor in the list of messages.
When the internal COFA is deasserted, MUSYCC generates an Interrupt
Descriptor with the COFA error encoding if the interrupt is not masked in the
Group Configuration Descriptor. If a synchronization signal is received
(low-to-high transition on TSYNC or RSYNC) while the internal COFA is
asserted, an Interrupt Descriptor with the COFA interrupt encoding is generated
immediately if this interrupt is not masked. COFA detection is not applicable to
the N x 64 serial port mode.
4.5.5 Out-of-Frame
The Receiver Out-of-Frame (ROOF) signal is asserted by the physical T1 or E1
interface sourcing the channelized data to MUSYCC. This signal indicates the
interface device has lost frame synchronization.
In the case of multiplexed E1 lines (2xE1 or 4xE1), the ROOF input signal on
a given port can be asserted and deasserted as time slots are received from an
out-of-frame E1 followed by an in-frame E1.
The state of ROOF is evaluated on a bit-by-bit basis when processing data
from a time slot. When ROOF assertion is detected by the receiver serial
interface, MUSYCC checks the OOFABT bit in the Group Configuration
Descriptor. If the OOFABT bit is set (i.e., 1), MUSYCC terminates any active
messages for all mapped and active channels in the channel group. If the
OOFABT bit is not set (i.e., 0), MUSYCC continues to process the received data
but still asserts the OOF Interrupt Descriptor unless it is masked.
For each receive message terminated during the OOF condition, the
corresponding Message Descriptor’s owner bit is returned to the host, and a
Buffer Status Descriptor is written with the OOF error encoding. The Buffer
Status Descriptor is written to host memory only if configured to do so on a per
group basis in the Group Configuration Descriptor.
MUSYCC then proceeds to the next Message Descriptor in the list of messages.
Two frame synchronization events (via external sync or flywheel sync) after ROOF is
asserted, MUSYCC generates an interrupt descriptor with the OOF error encoding if
the interrupt is not masked in the Group Configuration Descriptor.
As ROOF is deasserted, MUSYCC immediately restarts normal bit level
processing on all mapped and active channels. Two frame synchronization events
after deassertion of ROOF is detected, MUSYCC generates an interrupt
descriptor with the Frame Recovery (FREC) interrupt encoding if the interrupt is
not masked (as indicated in Table 5-10, Group Configuration Descriptor).
4-8
Conexant
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.6 Serial Port Mapping
4.6 Serial Port Mapping
MUSYCC contains up to eight serial ports with each port associated to a channel
group processor that supports up to 32 logical bidirectional channels.
To manage more than 32 logical channels on a single port, the port
configuration options provided in the PORTMAP bit field (as described in
Table 5-6, Global Configuration Descriptor) can be programmed to route the
signal on one port to multiple channel groups. Figure 4-5 illustrates the serial port
mapping options.
Figure 4-5. Serial Port Mapping Options
PORTMAP = 0
PORTMAP = 1
Channel Group Processor 0
Serial Port 0
Channel Group Processor 1
Serial Port 1
Channel Group Processor 2
Serial Port 2
Channel Group Processor 3
Serial Port 3
Channel Group Processor 4
Serial Port 4
Channel Group Processor 5
Serial Port 5
Channel Group Processor 6
Serial Port 6
Channel Group Processor 7
Serial Port 7
Channel Group Processor 0
Serial Port 0
Channel Group Processor 1
Channel Group Processor 2
Serial Port 1
Channel Group Processor 3
Channel Group Processor 4
Serial Port 2
Channel Group Processor 5
Channel Group Processor 6
Serial Port 3
Channel Group Processor 7
PORTMAP = 2
Channel Group Processor 0
Serial Port 0
Channel Group Processor 1
Channel Group Processor 2
Channel Group Processor 3
Channel Group Processor 4
Serial Port 1
Channel Group Processor 5
Channel Group Processor 6
Channel Group Processor 7
8478_017
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
4.6 Serial Port Mapping
The following port mappings are available:
•
•
•
PORTMAP = 0, 1x port mode
Default mode after device reset. Each serial port is logically connected to
one channel group, and each port terminates up to 32 bidirectional
channels.
PORTMAP = 1, 2x port mode
Each of two serial ports is logically connected to two channel groups. In
this mode, serial port 0 is connected to channel groups 0 and 1, serial port
1 is connected to channel groups 2 and 3, serial port 2 is connected to
channel group 4 and 5, and serial port 3 is connected to channel group 6
and 7. Each serial port terminates up to 64 bidirectional channels.
PORTMAP = 2, 4x port mode
Serial port 0 is logically connected to channel groups 0, 1, 2, and 3, and
serial port 1 is logically connected to channel groups 4, 5, 6, and 7. Serial
ports 2 through 7 are disabled.
Mapping a serial port to one or more logical channels in a channel group is one
element of serial port configuration; another is indicating the channelized data
rate of the serial interface, accomplished by configuring the PORTMAP bit field
(Table 5-6, Global Configuration Descriptor). The connection between the serial
port and the physical layer interface indicates the relationship to physical layer
time slots.
Each serial port can be configured to support 24, 32, 64, 128 or a variable
number of 8-bit time slots up to 128. Each serial port can be configured to
support data rates up to and including 8.192 Mbps. Also, each serial port can be
independently wired to a separate source of serial data, or all four serial ports can
be wired to a single source of serial data.
4-10
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™) 4.7 Tx and Rx FIFO Buffer Allocation and Manage-
4.7 Tx and Rx FIFO Buffer Allocation and
Management
Each channel group contains a separate internal buffer memory space for transmit
and receive operations. Within each of these spaces, separate areas are set aside
for specific functions.
Each channel within the group must be allocated buffer space before the
channel can be activated. Table 4-2 lists the internal buffer memory allocation.
This space acts as a holding buffer for incoming (Rx) and outgoing (Tx) data.
Data buffers for each channel are allocated using the BUFFLOC and BUFFLEN
bit fields (Table 5-18, Channel Configuration Descriptor). Both receiver and
transmitter of a channel use a data buffer scheme where half the available FIFO
services the serial interface, and the other half services data in shared memory.
Figures 4-6 and 4-7 illustrate the receive and transmit data flows, respectively.
BUFFLEN+1 specifies half the size of the buffer space allocated to a direction of
the channel.
Table 4-2. Internal Buffer Memory Layout
Memory Area
Transmit
Receive
Fixed Data Buffer
64 dwords
64 dwords
Subchannel Map
(or Additional Data Buffer if No Subchanneling)
64 dwords
64 dwords
Time Slot Map
32 dwords
32 dwords
Total
160 dwords
640 bytes
160 dwords
640 bytes
Figure 4-6. Receive Data Flow
Control
1/2 FIFO
Receive
Channel
BLP
Shared
Memory
DMAC
Data
Data
1/2 FIFO
PCI
Bus
Internal Data Buffer
8478_018
NOTE(S): 1/2 FIFO = BUFFLEN+1
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4.0 Serial Interface
4.7 Tx and Rx FIFO Buffer Allocation and Management
Multichannel Synchronous Communications Controller
Figure 4-7. Transmit Data Flow
Control
1/2 FIFO
Transmit
Channel
BLP
Shared
Memory
DMAC
Data
Data
1/2 FIFO
PCI
Bus
Internal Data Buffer
8478_019
NOTE(S): 1/2 FIFO = BUFFLEN+1
The allocation of internal data buffers requires an understanding of how the
total available FIFO buffer space depends on whether subchannels are enabled
within that channel group. Table 4-2 specifies 64 dwords of internal data buffer
are available to allocate as FIFO buffer space among the 32 channels of each
channel group when any channel within that group is configured to operate as a
subchannel (SUBDSBL = 0 in the Group Configuration Descriptor). Table 4-2
further specifies that an additional 64 dwords of internal data buffer (128 dwords
total) are available to allocate as FIFO buffer space among the channel group by
reusing the subchannel map area when all subchanneling within that group is
disabled (SUBDSBL = 1).
Other important considerations for allocating internal data buffers include the
number of active channels per group, the channels’ data rate, and the channels’
PCI latency tolerance. Examples given later in this section describe scenarios
where all available internal data buffer space is evenly distributed to form equal
length FIFO buffers for each channel in the group, presuming each channel
operates at the same data rate, and there are a variable number of channels per
group. However, internal data buffer allocation is flexible and allows the host to
assign larger FIFO buffers to channels operating at higher data rates. For
applications operating high speed channels (i.e., hyperchannels), the host
typically allocates 2 dwords (64 bits) of internal data buffer for each 64 kbps
increment in the channel’s data rate. For example, a 1920 kbps hyperchannel
consisting of 30 time slots would typically be allocated 60 dwords of FIFO buffer
space. Smaller FIFO buffers can be allocated if there are multiple, high-speed
channels configured within one group, but at the expense of some PCI latency
tolerance.
PCI latency tolerance equals the maximum length of time a particular channel
can operate normally between PCI bus transactions without reaching an internal
buffer overflow or underflow condition. Therefore, PCI latency tolerance is
primarily dependent on each channel’s FIFO buffer size. Because of MUSYCC’s
internal data buffer scheme, each transmit channel’s PCI latency tolerance is
expressed as the amount of time required to send data from half the FIFO buffer
size [(i.e., (BUFFLEN + 1) dwords)]. While a receive channel’s PCI latency
tolerance is expressed as 1/2 FIFO buffer size plus 1 additional dword
[i.e., (BUFFLEN + 2) dwords]. A 64 kbps channel that is allocated 4 dword
transmit and receive FIFO buffers can tolerate up to 2 dwords (1 ms) of bus
latency in the transmit direction and 3 dwords (1.5 ms) of bus latency in the
receive direction.
4-12
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™) 4.7 Tx and Rx FIFO Buffer Allocation and Manage-
4.7.1 Example Channel BUFFLOC and BUFFLEN Specification
With some subchanneling, only the Fixed Data Buffer (total of 64 dwords) is the
area available for Internal Data Buffer usage. If the buffer space is evenly divided
across 32 channels, the BUFFLOC and BUFFLEN specifications would be as
described in Table 5-18, Channel Configuration Descriptor. Table 4-3 lists the
subchannel buffer allocation on 32 channels.
Table 4-3. Example of 32-Channel with Subchanneling Buffer Allocation (Receive or Transmit)
Within Channel Descriptor
Channel
Number
BUFFLOC
(dword Offset from Start of
Fixed Data Buffer)
BUFFLEN(1)
0
0
0
1
1
0
2
2
0
...
...
...
31
31
0(2)
NOTE(S):
(1)
(2)
Assuming all channels within a group operate at the same bit rate, BUFFLEN = [(Total dwords ÷ Number of Channels) ÷ 2]–1.
BUFFLEN values larger than 1Fh do not increase the PCI burst length. BUFFLEN determines the number of dwords burst
during a PCI read/write operation to fill or flush the internal data buffer. For example, BUFFLEN = 1Fh specifies a burst length
of 32 dwords.
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4.0 Serial Interface
Multichannel Synchronous Communications Controller
4.7 Tx and Rx FIFO Buffer Allocation and Management
With no subchanneling, the Fixed Data Buffer area plus the Subchannel Map
area are available for Internal Data Buffer usage (total of 128 dwords). If the
buffer space is evenly divided across 32 channels, the BUFFLOC and BUFFLEN
specification is as listed in Table 4-4, for 32 channels without subchannel buffer
allocation.
Table 4-4. Example of 32-Channel without Subchanneling Buffer Allocation (Receive or Transmit)
Within Channel Descriptor
Channel
Number
BUFFLOC
(dword Offset from Start of
Fixed Data Buffer)
BUFFLEN(1)
0
0
1
1
2
1
2
4
1
...
...
...
31
62
1(2)
NOTE(S):
(1)
(2)
Assuming all channels within a group operate at the same bit rate, BUFFLEN = [(Total dwords ÷ Number of Channels) ÷ 2]–1.
BUFFLEN values larger than 1Fh do not increase the PCI burst length. BUFFLEN determines the number of dwords burst
during a PCI read/write operation to fill or flush the internal data buffer. For example, BUFFLEN = 1Fh specifies a burst length
of 32 dwords.
If the buffer space is evenly divided across 16 channels, the BUFFLOC and
BUFFLEN specification would be as listed in Table 4-5, for 16 channels with
subchannel buffer allocation.
Table 4-5. Example of 16-Channel without Subchanneling Buffer Allocation (Receive or Transmit)
Within Channel Descriptor
Channel
Number
BUFFLOC
(dword Offset from Start of
Fixed Data Buffer)
BUFFLEN(1)
0
0
3
1
4
3
2
8
3
...
...
...
15
60
3(2)
NOTE(S):
(1)
(2)
4-14
Assuming all channels within a group operate at the same bit rate, BUFFLEN = [(Total dwords ÷ Number of Channels) ÷ 2]–1.
BUFFLEN values larger than 1Fh do not increase the PCI burst length. BUFFLEN determines the number of dwords burst
during a PCI read/write operation to fill or flush the internal data buffer. For example, BUFFLEN = 1Fh specifies a burst length
of 32 dwords.
Conexant
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4.0 Serial Interface
Multichannel Synchronous Communications Controller (MUSYCC™) 4.7 Tx and Rx FIFO Buffer Allocation and Manage-
4.7.2 Receiving Bit Stream
As a receive channel is activated, MUSYCC reads in descriptors from shared
memory and prepares Rx-BLP and Rx-DMAC to service incoming serial data
accordingly, assuming all configurations are proper, and incoming data can be
written to shared memory.
Upon channel activation, the receiver starts storing received data into a
BUFFLEN+1 size of FIFO, starting at BUFFLOC offset in the FIFO buffer area.
As this buffer fills, the BLP instructs the DMAC to start a PCI data transfer cycle
to shared memory of the FIFO buffer contents and simultaneously starts filling
another BUFFLEN+1 size of FIFO buffer from the serial port. Generally, half the
FIFO buffer space for a channel is used for serial port data reception, and half for
shared memory data transfers.
The DMAC-initiated PCI transfer cycle requires MUSYCC to arbitrate for the
PCI bus, initiate a master write to shared memory over the PCI bus, and conclude
the transfer by releasing the PCI bus. MUSYCC transfers data autonomously and
always attempts to burst data to the PCI.
4.7.3 Transmitting Bit Stream
When a transmit channel is activated, MUSYCC reads in descriptors from shared
memory and prepares Tx-BLP and Tx-DMAC to service outgoing serial data,
assuming all configurations are proper, and outgoing data can be read from
shared memory.
Upon channel activation, the transmitter initiates a PCI data transfer cycle
from shared memory of data to be output to the serial port. As the DMAC
receives data over the PCI, it forwards it to the BLP which fills a BUFFLEN+1
size of FIFO starting at BUFFLOC offset in the FIFO area. Generally, half the
FIFO space for a channel is used for serial port data transmission and half for
shared memory data transfers.
The DMAC-initiated PCI transfer cycle requires that MUSYCC arbitrate for
the PCI bus, initiate a master read from shared memory over the PCI bus, and
conclude the transfer by releasing the PCI bus. MUSYCC transfers data
autonomously and always attempts to burst data from the PCI.
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4.0 Serial Interface
Multichannel Synchronous Communications Controller
4.7 Tx and Rx FIFO Buffer Allocation and Management
4.7.3.1 Transmit Data
Bit Output Value
Determination
The TDAT signal from MUSYCC is the only output signal in the serial interface.
For each bit time specified by the TCLK input signal to MUSYCC and on each
active edge for a data bit specified by the TDAT_EDGE bit field, a value for the
TDAT bit must be determined and output (Table 5-12, Port Configuration
Descriptor). Figure 4-8 illustrates the logic used to determine the output value.
Figure 4-8. Transmit Data Bit Output Value Determination
if ( TRANSMITTER_NOT_ENABLED )(1)
TDAT <= three-state
else
if ( CHANNEL_IS_MAPPED )(2)
if ( CHANNEL_IS_ACTIVATED )(3)
TDAT = BLP_OUTPUT(4)
else
TDAT = `logic 1'
else
if ( THREE_STATE_OUTPUT )(5)
TDAT = three-state
else
TDAT = `logic 1'
8478_020
NOTE(S):
(1)
(2)
(3)
(4)
(5)
4-16
TRANSMITTER_NOT_ENABLED. (Check TXENBL bit field in Table 5-10, Group Configuration Descriptor.)
CHANNEL_IS_MAPPED. (Verify channel to time slot mapping enabled in Table 5-14, Transmit or Receive Time Slot Map.)
CHANNEL_IS_ACTIVATED. Verify Channel Activate Service Request issued.
BLP_OUTUT. Data taken from shared memory, through the internal FIFO and ready for transmission.
THREE_STATE_OUTPUT. Check TRITX bit field in Port Configuration Descriptor.
Conexant
100660E
5
5.0 Memory Organization
MUSYCC interfaces with a system host using a set of data structures located in a
shared memory region. MUSYCC also contains a set of internal registers which
the host can configure and which controls MUSYCC. This section describes the
various shared memory data structures and the layout of individual registers
which are required for the operation of MUSYCC.
5.1 Memory Architecture
MUSYCC supports a memory model whereby data is continually moved into and
out of a linked list of data buffers in shared memory for each active channel. This
assumes a system topology in which a host and MUSYCC both have access to
shared memory for data control and data flow. The data structures are defined in a
way that the control structures and the data structures may or may not reside in the
same physical memory and may or may not be contiguous. The host allocates and
deallocates the required memory space as well as the size and number of data
buffers within that space.
Different versions of MUSYCC support different numbers of channel groups.
The host allocates shared memory regions to configure and control each group.
Figure 5-1 illustrates the memory model used by MUSYCC for control and
data structures required for each supported channel group.
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5.0 Memory Organization
5.1 Memory Architecture
Multichannel Synchronous Communications Controller (MUSYCC™)
Figure 5-1. Shared Memory Model Per Channel Group
Group Base Pointer
Tx Message Pointer – Ch 00
Tx Message Pointer – Ch .....
Tx Message Pointer – Ch 31
Msg 2*
Tx Head Pointer – Ch 00
Tx Head Pointer – Ch.....
Tx Head Pointer – Ch 31
Tx Channel Config Table
Rx Time Slot Map
Rx Subchannel Map
Rx Channel Config Table
Global Configuration
Interrupt Queue
Group Configuration
Msg 1*
Msg 2*
Tx Time Slot Map
Tx Subchannel Map
Data Buffer
Buffer Descriptor
Data Buffer Pointer
Next Message Pointer
Buffer Descriptor
Data Buffer Pointer
Data Buffer
Data Buffer
Receive Message List
Msg 3*
Rx Message Pointer – Ch 31
Data Buffer Pointer
Next Message Pointer
Next Message Pointer
Rx Head Pointer – Ch 00
Rx Head Pointer – Ch ....
Rx Head Pointer – Ch 31
Rx Message Pointer – Ch 00
Rx Message Pointer – Ch ....
Buffer Descriptor
Msg 3*
Channel Group Descriptor
Msg 1*
Transmit Message List
Buffer Descriptor
Data Buffer Pointer
Data Buffer
Next Message Pointer
Buffer Descriptor
Data Buffer Pointer
Data Buffer
Next Message Pointer
Buffer Descriptor
Data Buffer Pointer
Data Buffer
Next Message Pointer
* See Table 5-19 for structure of Message Descriptor.
Memory Protection
Message Length
Port Configuration
8478_021
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.1 Memory Architecture
5.1.1 Register Map Access and Shared Memory Access
During MUSYCC’s PCI initialization, the system controller allocates a dedicated
1 MB memory range to each of MUSYCC’s PCI functions. The memory range
allocated to MUSYCC must not map to any other physical or shared memory.
Instead, the system configuration manager allocates a logical memory address
range, and notifies the system or bus controllers that any access to these ranges
must result in a PCI access cycle. MUSYCC is assigned these address ranges for
each function through the PCI configuration cycle. Once configured, MUSYCC
becomes a functional PCI device on the bus.
As the host accesses MUSYCC’s allocated address ranges, it initiates the
access cycles on the PCI bus. It is up to individual MUSYCC devices on the bus
to claim the access cycle. As its address ranges are accessed, MUSYCC behaves
as a PCI slave device while data is being read or written by the host. MUSYCC
responds to all access cycles where the upper 12 bits of a PCI address match the
upper 12 bits of either the EBUS Base Address register (Function 1) or the
MUSYCC Base Address register (Function 0).
For MUSYCC’s Function 1, a 1 MB memory space is assigned to the EBUS
Base Address register which is written into Function 1 PCI configuration space
(Table 2-14, Register 4, Address 10h). Devices connected to the EBUS can then
be allocated memory addresses within this 1 MB memory range. If MUSYCC
claims a PCI access cycle for Function 1, MUSYCC initiates EBUS arbitration
and ultimately accesses data from a device connected to the EBUS.
For MUSYCC’s Function 0, a 1 MB memory space is assigned to the
MUSYCC Base Address register which is written into Function 0 PCI
configuration space (Table 2-7, Register 4, Address 10h). Once a base address is
assigned to Function 0, a register map is used to access individual device resident
registers. The register map provides the byte offset from the Base Address register
where registers reside. The register map layout is listed in Table 5-1.
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.1 Memory Architecture
The 1 MB memory ranges assigned to MUSYCC functions will not restrict
MUSYCC’s PCI interface from attempting to access these ranges. The host must
be cognizant that MUSYCC cannot respond to an access cycle which MUSYCC
itself initiates as the bus master.
Table 5-1. MUSYCC Register Map
Group
(Byte Offset from Base Address Register)
Register Map
Group Base Pointer
0
1
2
3
4
5
6
7
0000h
0800h
1000h
1800h
2000h
2800h
3000h
3800h
2808h
3008h
3808h
00004h
Dual Address Cycle Base Pointer(1)
Service Request Descriptor
0008h
0808h
1008h
1808h
2008h
000Ch
Interrupt Status Descriptor(1)
Transmit Time Slot Map(2)
0200h
0A00h
1200h
1A00h
2200h
2A00h
3200h
3A00h
Transmit Subchannel Map(2)
0280h
0A80h
1280h
1A80h
2280h
2A80h
3280h
3A80h
Transmit Channel Configuration
Table(2)
0380h
0B80h
1380h
1B80h
2380h
2B80h
3380h
3B80h
Receive Time Slot Map(2)
0400h
0C00h
1400h
1C00h
2400h
2C00h
3400h
3C00h
Receive Subchannel Map(2)
0480h
0C80h
1480h
1C80h
2480h
2C80h
3480h
3C80h
Receive Channel Configuration
Table(2)
0580h
0D80h
1580h
1D80h
2580h
2D80h
3580h
3D80h
Global Configuration Descriptor(1)
00600h
Interrupt Queue Descriptor(1)
00604h
Group Configuration Descriptor
060Ch
0E0Ch
160Ch
1E0Ch
260Ch
2E0Ch
360Ch
3E0Ch
Memory Protection Descriptor
0610h
0E10h
1610h
1E10h
2610h
2E10h
3610h
3E10h
Message Length Descriptor
0614h
0E14h
1614h
1E14h
2614h
2E14h
3614h
3E14h
Port Configuration Descriptor
0618h
0E18h
1618h
1E18h
2618h
2E18h
3618h
3E18h
Receive BIST Status(3)
00640h
Transmit BIST Status(3)
00644h
NOTE(S):
(1)
(2)
(3)
5-4
MUSYCC automatically maps Group 1 through 7 addresses for these registers to the Group 0 address (shown). For example,
accessing address 00E00h in MUSYCC (address for Group 1 Global Configuration register) automatically maps to address
00600h and the contents of 00600h is read or written.
The following descriptors are mapped to Internal RAM: Transmit Time Slot Map, Transmit Subchannel Map, Transmit
Channel Configuration Table, Receive Time Slot Map, Receive Subchannel Map, and Receive Configuration Table. Host must
not access internal RAM while channels are active. Updates to RAM must be performed via a service request.
The receive/transmit BIST diagnostic status registers.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.1 Memory Architecture
The first four registers in each group (shown in bold-type in Table 5-1) are
located exclusively within MUSYCC. These registers are accessed by the host
using direct reads and writes to the corresponding register map address. The
remaining registers have corresponding locations within shared memory, and the
host accesses the shared memory image rather than the internal registers.
Regardless, the values within MUSYCC are always the values used during device
operation. After configuring the shared memory image of these registers, the host
issues a service request by writing directly into the Service Request Descriptor.
This causes MUSYCC to copy the image from shared memory.
Each supported channel group requires its own group structure to operate. The
Dual Address Cycle Base Pointer, Interrupt Status Descriptor, Global
Configuration Descriptor, and the Interrupt Queue Descriptor are common
among all supported groups.
The Transmit Time Slot Map and the Transmit Subchannel Map are
write-only areas within MUSYCC; reading from these areas results in all 1s being
returned.
The Service Request Descriptors are locations within MUSYCC where
commands can be directed to individual channel groups. The host writes a service
request (a command) directly into the corresponding group’s register. MUSYCC
behaves as a PCI slave as this write is performed. The action resulting from the
command may cause MUSYCC to read or write locations from shared memory.
While MUSYCC accesses shared memory, it behaves as a PCI master and
arbitrates for control of the bus autonomously.
MUSYCC’s registers can be initialized before or after shared memory resident
descriptors are initialized. The recommended sequence is to configure shared
memory descriptors first, then copy the relevant information to MUSYCC’s
registers via the service request mechanism.
NOTE:
100660E
Upon channel activation, shared memory and internal registers must be
initialized, valid, and available to MUSYCC. MUSYCC uses the
information within the shared memory descriptors to transfer data between
the serial interface and shared memory. MUSYCC assumes the
information is valid once a channel is activated.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.1 Memory Architecture
The first four sets of pointers for each channel group, listed in Table 5-2,
Group Structure Memory Map, are pointer locations exclusive to shared memory.
MUSYCC does not keep these values internally although they are accessed
regularly during channel processing. The remaining locations have a
corresponding register within MUSYCC.
Table 5-2. Group Structure Memory Map
Byte Offset from Respective
Group Base Pointer
Length (Bytes)
Transmit Head Pointers
00000h
128
Transmit Message Pointers
00080h
128
Receive Head Pointers
00100h
128
Receive Message Pointers
00180h
128
Transmit Time Slot Map
00200h
128
Transmit Sub Channel Map
00280h
256
Transmit Channel Configuration Table
00380h
128
Receive Time Slot Map
00400h
128
Receive Sub Channel Map
00480h
256
Receive Channel Configuration Table
00580h
128
Global Configuration Descriptor
00600h
4
Interrupt Queue Descriptor
00604h
8
Group Configuration Descriptor
0060Ch
4
Memory Protection Descriptor
00610h
4
Message Length Descriptor
00614h
4
Port Configuration Descriptor
00618h
4
Total Space Required
1564
Channel Group Memory Map
5.1.2 Memory Access Illustration
Assume the system memory controller (or the host) allocates addresses for
MUSYCC’s PCI functions as listed in Table 5-3.
Table 5-3. MUSYCC PCI Function Memory Allocation
System Allocated MUSYCC Memory Ranges
Start Address
End Address
Length
MUSYCC - Function 0- Base Address Register
0240 0000h
024F FFFFh
1 MB
EBUS - Function 1- Base Address Register
0340 0000h
034F FFFFh
1 MB
5-6
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.1 Memory Architecture
The Base Address is written into MUSYCC by the host-initiated PCI
configuration access write cycles. After MUSYCC functions are
memory-mapped to PCI space, the host allocates shared memory space for each
supported channel group descriptors. It requires each Group Base Pointer to start
on a 2 kB boundary, as listed in Table 5-4 and Table 5-8, Group Base Pointer.
Table 5-4. Shared Memory Allocation—Group Descriptors
Channel Group
Descriptors
Start Address
End Address
Length
Group 0 Base Pointer
0090 0000h
0090 061Ch
1,564 bytes
Group 1 Base Pointer
0090 0800h
0090 0E1Ch
1,564 bytes
Group 2 Base Pointer
0090 1000h
0090 161Ch
1,564 bytes
Group 3 Base Pointer
0090 1800h
0090 1E1Ch
1,564 bytes
Group 4 Base Pointer
0090 2000h
0090 261Ch
1,564 bytes
Group 5 Base Pointer
0090 2800h
0090 2E1Ch
1,564 bytes
Group 6 Base Pointer
0090 3000h
0090 361Ch
1,564 bytes
Group 7 Base Pointer
0090 3800h
0090 3E1Ch
1,564 bytes
The Group Base Pointer value is written into MUSYCC by the host via PCI
write access cycles. The location of the Group Base Pointer register for each
group within MUSYCC is listed in Table 5-1.
For this illustration, the host must perform the following write operations, as
listed in Table 5-5.
Table 5-5. Host Assigns Group Base Pointers
100660E
Host Writes Pointer Value
To PCI Address
0090 0000h
0240 0000h
0090 0800h
0240 0800h
0090 1000h
0240 1000h
0090 1800h
02401800h
0090 2000h
0240 2000h
0090 2800h
0240 2800h
0090 3000h
0240 3000h
0090 3800h
02403800h
Conexant
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5.0 Memory Organization
5.1 Memory Architecture
Multichannel Synchronous Communications Controller (MUSYCC™)
Next, the host allocates the required shared memory for transmit and receive
messages. Assume, for example, the host needs 8 message descriptors for each
channel and direction, and each corresponding data buffer per message is 100h
(256) bytes in length.
Memory for Message Descriptors =
32 channels/group *
2 directions/channel *
12 bytes/message descriptor *
8 buffers/channel
= 1800h bytes/group
= 6144 bytes/group
Memory for Data Buffers =
32 channels/group *
2 directions/channel *
8 buffers/channel *
256 bytes/buffer
= 131, 072 bytes/group
= 20,000h bytes/group
Further, the host may choose to allocate all the memory contiguously, or it
may allocate the memory for message descriptors separately from data buffers. In
this case, message descriptors for 8 Channel Groups may be merged into a
contiguous block of memory [(1800h x 8 = C000h) bytes in length].
5-8
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2 Descriptors
This section further details the descriptors specified in the MUSYCC memory
model. The MUSYCC descriptors are as follows:
1.
2.
3.
4.
5.
Host Interface Level Descriptors (see Section 5.2.1)
– Global Configuration
– Dual Address Cycle Base Pointer
Channel Group Level Descriptors (see Section 5.2.2)
– Group Base Pointer
– Service Request
– Group Configuration
– Memory Protection
– Port Configuration
– Message Length
– Time Slot Map
– Subchannel Map
Channel Level Descriptors (see Section 5.2.3)
– Channel Configuration (see Section 5.2.4)
Message Level Descriptor
– Head Pointer
– Message Pointer
– Message Descriptor
– Buffer Descriptor
– Buffer Status Descriptor
– Next Message Pointer
– Data Buffer Pointer
– Message Descriptor Handling
Interrupt Level Descriptors (see Section 5.2.5)
– Interrupt Queue Descriptor
– Interrupt Descriptor
– Interrupt Status Descriptor
Each of the above entities are allocated, deallocated, read from, and written to
by the host. MUSYCC can read all of these entities as well, but can only write to
these:
•
•
•
100660E
Message Pointers
Buffer Status Descriptors
Receive Data Buffers
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.1 Host Interface Level Descriptors
Host interface-level descriptors contain information necessary to configure the
global registers. This information applies to the entire device, including all
channel groups, serial ports, and channels.
5.2.1.1 Global
Configuration Descriptor
The Global Configuration Descriptor specifies configuration information
applying to the entire device including all channel groups, serial ports, and
channels.
Memory space is reserved for the Global Configuration Descriptor within
each Channel Group Descriptor. By convention, the values corresponding to
Channel Group 0 (a group present in all versions of MUSYCC) provides the
correct data. The host coordinates how this data is transferred into MUSYCC by:
•
•
Instructing MUSYCC to read the Channel Group 0 Global Configuration
Descriptor when setting the global data.
Copying the Channel Group 0 Global Configuration Descriptor to all other
supported Channel Group Descriptors and requesting a global
initialization service request operation for any supported channel groups.
The components and their descriptions are listed in Table 5-6.
Table 5-6. Global Configuration Descriptor (1 of 2)
Bit
Field
Name
31
30
29
28
TCLKACT7
TCLKACT6
TCLKACT5
TCLKACT4
27
26
25
24
RCLKACT7
RCLKACT6
RCLKACT5
RCLKACT4
23
22
21
20
TCLKACT3
TCLKACT2
TCLKACT1
TCLKACT0
19
18
17
16
RCLKACT3
RCLKACT2
RCLKACT1
RCLKACT0
15
RSVD
0
14:12
BLAPSE[2:0]
0–7
11
ECKEN
0
Expansion Bus Clock Disabled. ECLK output is three-stated.
1
Expansion Bus Clock Enabled. MUSYCC redrives and inverts PCLK input onto ECLK
output pin.
5-10
Value
Description
Transmit and Receive Line Clock Activity Indicator.
0,1,2, 3, 4, 5, 6, or 7 corresponds to a channel group number.
Read Only. Reset to 0 after each read.
Each indicator bit is cleared when the respective channel group is reset via PCI
Reset, Soft Group Reset, or Soft Chip Reset.
The TCLKACTx corresponds to TCLKx line clock.
The RCLKACTx corresponds to RCLKx line clock.
The indicator is set to 1 on the second rising edge of the corresponding serial
interface line clock, and the previous value for the indicator bit was 0.
If multiple channel groups are mapped to a single serial port, one clock is driving
each channel group. The indicator bits reflect the activity of the clock driving the
channel group.
If MUSYCC does not detect a line clock, the value of the indicator bit(s) remain at
the reset value 0.
Reading from channel group RAM during the absence of a line clock results in the
dword DEADACCEh (dead access) being returned. Writing to channel group RAM
during the absence of a line clock results in the write being ignored.
Reserved.
Expansion Bus Access Interval. MUSYCC waits BLAPSE+4 number of ECLK periods
immediately after relinquishing the bus. This wait ensures that all the bus grant signals
driven by the bus arbiter have sufficient time to be deasserted as a result of bus
request signals being deasserted by MUSYCC.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-6. Global Configuration Descriptor (2 of 2)
Bit
Field
Name
Value
Description
10
MPUSEL
0
Expansion Bus Microprocessor Selection, Motorola-style. Expansion bus supports the
Motorola-style microprocessor interface and uses Motorola signals: Bus Request
(BR*), Bus Grant (BG*), Address Strobe (AS*), Read/Write (R/WR*), and Read Strobe
(RD*).
1
Expansion Bus Microprocessor Selection, Intel-style. Expansion bus supports the
Intel-style microprocessor interface and uses Intel signals: Hold Request (HOLD), Hold
Acknowledge (HLDA), Address Latch Enable (ALE*), Write Strobe (WR*), and Data
Strobe (DS*).
Expansion Bus Address Duration. MUSYCC extends the duration of valid address bits
during an EBUS address phase to ALAPSE+1 number of ECLK periods. The control
lines ALE* (Intel) or AS* (Motorola) indicate that the address bits have had the desired
setup time.
9:8
ALAPSE[1:0]
0–3
7
RSVD
0
6:4
ELAPSE[2:0]
0–7
3
INTAMSK
0
INTA interrupt enabled.
1
INTA interrupt disabled.
0
INTB interrupt enabled.
1
INTB interrupt disabled.
0
Default.
Port 0 mapped to Channel Group 0.
Port 1 mapped to Channel Group 1.
Port 2 mapped to Channel Group 2.
Port 3 mapped to Channel Group 3.
Port 4 mapped to Channel Group 4.
Port 5 mapped to Channel Group 5.
Port 6 mapped to Channel Group 6.
Port 7 mapped to Channel Group 7.
1
Port 0 mapped to Channel Groups 0 and 1.
Port 1 mapped to Channel Groups 2 and 3.
Port 2 mapped to Channel Groups 4 and 5.
Port 3 mapped to Channel Groups 6 and 7.
2
Port 0 mapped to Channel Groups 0, 1, 2, and 3.
Port 1 mapped to Channel Groups 4, 5, 6, and 7.
3
Reserved.
2
1:0
100660E
INTBMSK
PORTMAP[1:0]
Reserved.
Expansion Bus Data Duration. MUSYCC extends the duration of valid data bits during
an EBUS data phase to ELAPSE+1 number of ECLK periods. The control lines RD* and
WR* (Intel) or DS* and R/WR* (Motorola) indicate that the data bits have had the
desired setup time.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.1.2 Dual Address
Cycle Base Pointer
MUSYCC supports 32-bit and 64-bit memory addressing. The Dual Address
Cycle Base Pointer (DACBASE) supports 64-bit memory addressing and is
described in Table 5-7.
If the value of DACBASE is 0, MUSYCC initiates all memory access cycles
without dual-addressing. If the value is non-0, MUSYCC initiates all memory
access cycles with dual-addressing.
For cycles without dual-addressing, MUSYCC uses the AD[31:0] signal lines
to indicate the address of the memory access. During the address phase,
MUSYCC encodes the type of access cycle (e.g., read, write,...) in the
Command/Byte Enable signal lines, CBE[3:0]*. The address phase lasts one
PCLK period.
For cycles with dual-addressing, MUSYCC multiplexes a 64-bit address onto
the AD[31:0] signal lines and adds an additional PCLK period to the address
phase. To indicate 64-bit addressing, MUSYCC encodes the dual address code
onto the CBE[3:0]* signal lines during the first PCLK period of the address
phase. MUSYCC encodes the access type code (e.g., read, write) onto the
CBE[3:0]* signal lines during the second PCLK period of the address phase.
When MUSYCC accesses a 64-bit memory address using dual addressing, the
upper 32 bits of the address are fixed to a non-0 value from DACBASE. To
change from 64-bit addressing to 32-bit addressing, the value of DACBASE must
be zeroed. Although MUSYCC is capable of initiating 64-bit addressing when in
master mode, it responds only to 32-bit access cycles without dual-addressing.
Table 5-7. Dual Address Cycle Base Pointer
Bit
Field
Name
Value
Description
31:0
DACBASE[31:0]
—
Dual Address Cycle Base Pointer. A 32-bit base register when non-0 causes all
MUSYCC master operations (read/write) to use PCI Dual Address Cycle. The value
in this register would be the upper 32-bits of the 64-bit addressing.
5.2.2 Channel Group Level Descriptors
Channel Group Descriptors contain all information needed to configure one
channel group and the associated 32 logical channels, while maintaining pointers
to buffer descriptors for each channel and direction. The contents of the Channel
Group Descriptor are listed in Table 5-2, Group Structure Memory Map.
5.2.2.1 Group Base
Pointer
The Group Base Pointer (GBASE) register per channel group within the host
interface contains a 2 kB pointer aligned to a corresponding Channel Group
Descriptor in shared memory, as described in Table 5-8.
Table 5-8. Group Base Pointer
Bit
Field
Name
Value
31:11
GBASEx[20:0]
—
These 21 bits are appended with 11 0s to form a 2 k block-aligned 32-bit address
pointing to the first dword of the channel group structure for Channel Group x.
10:0
GBASEx[10:0]
0
These 11 bits appended to GBASE ensure 2 kB block alignment.
5-12
Description
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2.2.2 Service Request
5.2 Descriptors
The Service Request is a register per channel group within the host interface
containing a bit field where instructions are written to MUSYCC by the host. The
following instructions are supported:
•
•
•
•
•
•
•
•
Perform device reset and initialization
Perform channel group reset and initialization
Configure a channel
Read specific descriptors from within a Channel Group Descriptor
Activate a channel
Deactivate a channel
Jump (re)activate a channel
No-operation command
A service request is issued to a specific channel group within MUSYCC. The
channel group then acknowledges by sending a service request acknowledge
interrupt descriptor back to the host.
The soft-chip reset service request is the only service request not
acknowledged by MUSYCC.
Issuing multiple service requests to the same channel group successively
without first receiving acknowledgments from each request may cause the host to
lose track of which service request has been acknowledged, because MUSYCC
cannot uniquely acknowledge service requests for the same channel group. In
addition, issuing multiple simultaneous requests to the same channel group
causes indeterminate results within the channel group. To prevent these problems,
the host software must wait for a Service Request Acknowledgement (SACK)
after issuing any service request except for the soft chip reset request. The soft
chip reset request does not issue an acknowledgement, but this request is
guaranteed to be executed within two line clock periods.
Issuing a single service request to each supported channel group
simultaneously is supported, because MUSYCC acknowledges each one uniquely
with the Group ID bit field. Table 5-9 lists the bit fields and their descriptions of
the service request descriptor.
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-9. Service Request Descriptor (1 of 2)
Bit
Field
Name
Value
31:13
RSVD
0
Reserved.
12:8
SREQ[4:0]
0
No Operation. This service request performs no action other than to facilitate a
Service Request Acknowledge Interrupt (SACK). This would be used as a “UNIX
ping-like” operation to detect the presence of a channel group processor.
1
Soft Chip Reset. This is identical to a hardware reset. Set PORTMAP = 0, disable all
supported ports (both directions), and deactivate all 32 channels of all supported
groups (both directions). The Interrupt Status Descriptor is reset to point to the first
dword in the queue, and all indicator bits are reset.
This service request is not acknowledged by MUSYCC.
2
Soft Group Reset. This is similar to a hardware reset for a specified group and
direction. Disable all specified ports (both directions), and deactivate all 32 channels
of specified group (both directions).
3
Reserved.
4
Global Initialization. For the entire device, read the Global Configuration Descriptor
and the Interrupt Queue Descriptor from shared memory. This initialization is
performed following a hardware or soft-chip reset. The Interrupt Status Descriptor is
reset to point to the first dword in the queue, and all indicator bits are reset.
5
Group Initialization. For this group and direction, read the following from shared
memory:
Description
Time Slot Map
Subchannel Map
Channel Configuration Descriptor
Group Configuration Descriptor
Memory Protection Descriptor
Message Length Descriptor
Port Configuration Descriptor
This initialization must be performed by the host driver for each group and each
direction immediately following any reset or global initialization.(1)
5-14
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-9. Service Request Descriptor (2 of 2)
Bit
Field
Name
Value
12:8
SREQ[4:0]
6–7
Description
Reserved.
8
Channel Activation. For a specified channel and direction, initialize the channel, read
the head pointer, jump to the first message descriptor, and start processing the data
buffer.
This request starts processing a new message list. The effect of this request is
destructive to the current message being processed if the channel was already
activated and processing a message. This request is useful in aborting the current
message and starting a new message list.
9
Channel Deactivation. For a specified channel and direction, suspend channel activity.
10
Jump. For the receiver, this request is the same as the Channel Activation request. For
the transmitter, this request is useful for switching to a new message list after the
current message is completely transferred.
11
Channel Configure. For a specified channel and direction, read the Channel
Configuration Descriptor.
12–15
Reserved.
16
Read Global Configuration Descriptor.
17
Read Interrupt Queue Descriptor. The Interrupt Status Descriptor is reset to point to
the first dword in the queue, and all indicator bits are reset.
18
Read Group Configuration Descriptor.
19
Read Memory Protection Descriptor.
20
Read Message Length Descriptor.
21
Read Port Configuration Descriptor.
22–23
Reserved.
24
Read Time Slot Map. For this group and specified direction, read the Time Slot Map(1).
25
Read Subchannel Map. For this group and specified direction, read the Subchannel
Map(1).
26
Read Channel Configuration Table. For this group and specified direction, read the
Channel Configuration Table(1).
27–31
Reserved.
7:6
RSVD
0
Reserved.
5
DIR
0
Receive direction.
1
Transmit direction.
4:0
CH[4:0]
Channel number.
NOTE(S):
(1)
Time Slot Map, Subchannel Map, and Channel Configuration Description Table are read into MUSYCC only if a serial clock is
provided to the Serial Interface being configured.
100660E
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.2.3 Group
Configuration Descriptor
The Group Configuration Descriptor contains configuration bits applying to all
32 logical channels within a given channel group as listed in Table 5-10.
Table 5-10. Group Configuration Descriptor (1 of 2)
Bit
Field
Name
Value
31:22
RSVD
0
21:16
SUET[5:0]
15
SFALIGN
Description
Reserved.
Signal Unit Error Threshold. Sets maximum value of SUERM counter. When SUERM
exceeds this count, a SUERR interrupt is generated.
0
Super Frame Alignment. Flywheel Mechanism. Select roll over to 0 of time slot counter
(the flywheel mechanism in the serial interface) as a frame synchronization event.
For a transparent mode channel, wait for the flywheel to roll over to start message
processing after channel activation.
For descriptor polling, use the flywheel roll-over as a frame synchronization event.
The polling frequency is determined by using the poll-throttle field elsewhere in this
descriptor.
1
Super Frame Alignment. External Signal. Select detection of frame synchronization
signal (TSYNC or RSYNC) assertion as frame synchronization event.
For a transparent mode channel, wait for assertion of signal to start message
processing after channel activation.
For descriptor polling, use assertion of signal as frame synchronization event.
Polling frequency is determined by using poll-throttle field elsewhere in this descriptor.
14:12
RSVD
0
Reserved.
11:10
POLLTH[1:0]
0
Poll Throttle. Poll at every frame synchronization event. Not supported.
1
Poll at every 16th frame synchronization event.
2
Poll at every 32nd frame synchronization event.
3
Poll at every 64th frame synchronization event.
0
Inhibit Transmit Buffer Status Descriptor Disabled. At end of each transmitted data
buffer, do not inhibit (allow) overwriting of Tx Buffer Descriptor with a Tx Buffer Status
Descriptor.
1
Inhibit Transmit Buffer Status Descriptor. As the Tx Buffer Status Descriptor is being
inhibited, the host must rely on an interrupt for status information regarding
transmitted data message.
0
Inhibit Receive Buffer Status Descriptor Disabled. At the end of each Receive Data
Buffer, do not inhibit (allow) overwriting of Rx Buffer Descriptor with a Rx Buffer
Status Descriptor.
1
Inhibit Receive Buffer Status Descriptor. As the Rx Buffer Status Descriptor is being
inhibited, the host must rely on an interrupt for status information regarding the
received data message.
0
Memory Protection Violation Action. Reset Group. On a memory protection violation
error, group reset is performed. As a result, all 32 channels are deactivated in both
receive and transmit directions.
1
Memory Protection Violation Action. Deactivate Channel. On a memory protection
violation error, only the channel being serviced during violation is deactivated in both
receive and transmit directions.
9
8
7
5-16
INHTBSD
INHRBSD
MEMPVA
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-10. Group Configuration Descriptor (2 of 2)
Bit
Field
Name
Value
6
MCENBL
0
Message Configuration Bits Copy Disable. Not supported.
1
Message Configuration Bits Copy Enable. A set of configuration bits are copied from
the last transmit buffer descriptor of a message (with EOM = 1) into internal
configuration space and subsequently acted upon. The bits are used in specialized data
communications applications requiring non-default idle code transmission on a
per-message basis, inter-message pad fill, and/or message retransmission.
Direct writes to MUSYCC that change any message configuration bits remain
available. Only automatic copying from a transmit buffer descriptor (with the bit field
EOM set to 1) is disabled.
For a thorough discussion on message configuration bits see the Message
Configuration Bits subsection in the Protocol Support section.
0
Change of Frame Alignment Interrupt Enabled. If COFA is detected, generate Interrupt
Descriptor indicating COFA.
1
Change of Frame Alignment Interrupt Disabled. If COFA is detected, do not generate
Interrupt Descriptor.
0
Out of Frame/Frame Recovery Interrupt Enabled—Receive Only. If OOF/FREC is
detected, generate Interrupt Descriptor indicating OOF/FREC.
1
Out of Frame/Frame Recovery Interrupt Disabled—Receive Only. If an ABT, FCS, LNG,
or ALIGN error occurs, an OFF error is reported in the interrupt descriptor and buffer
status descriptor instead of these errors.
0
OOF Message Processing Enabled—Receive Only. When OOF condition is detected,
continue processing incoming data.
1
OOF Message Processing Disabled—Receive Only. Incoming messages on all
channels are aborted when the OOF condition is detected. HDLC channels recover
automatically after the OOF condition has cleared. However, Transparent mode
channels are automatically deactivated when the OOF condition is detected, and the
host must reactivate all Transparent channels after the OOF condition has cleared.
0
Subchanneling Enabled. Overrides Subchannel Enable bit for all time slots and allows
subchanneling.
1
Subchanneling Disabled. Overrides Subchannel Enable bit for all time slots and
disallows subchanneling.
Using this field to disable subchanneling frees Subchannel Descriptor Map memory
space for use as an extended data buffer space.
0
Transmitter Disabled. Logically resets time slot enable bits for all time slots. Transmit
data lines are three-stated. This logical, channel-group-wide state does not affect the
bit values in any time slot map.
1
Transmitter Enabled. Logically allows all channels with time slot enable bits set to start
processing data. This logical, channel-group-wide state does not affect the bit values
in any time slot map.
0
Receiver Disabled. Logically resets time slot enable bits for all time slots. This logical,
channel-group-wide state does not affect the bit values in any time slot map.
1
Receiver Enabled. Logically allows all channels with time slot enable bits set to start
processing data. This logical, channel-group-wide state does not affect the bit values
in any time slot map.
5
4
3
2
1
0
100660E
MSKCOFA
MSKOOF
OOFABT
SUBDSBL
TXENBL
RXENBL
Description
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.2.4 Memory
Protection Descriptor
The memory protection function is not implemented. This function must be
disabled by clearing the PROTENBL bit in the Memory Protection Descriptor.
Table 5-11 lists the bit field and description of the Memory Protection Descriptor.
Table 5-11. Memory Protection Descriptor
Bit
Field
Name
Value
31
PROTENBL
0
Memory Protection Disabled.
1
Memory Protection Enabled. Not supported.
0
Reserved.
30:28
RSVD
27:16
PROTHI[11:0]
15:12
RSVD
11:0
PROTLO[11:0]
5.2.2.5 Port
Configuration Descriptor
Description
Memory Protection High Address. Upper 12 bits (inclusive) of address for highest
memory location under protection.
0
Reserved.
Memory Protection Low Address. Upper 12 bits (inclusive) of the address for lowest
memory location under protection.
The Port Configuration Descriptor defines how MUSYCC interprets and
synchronizes the transmit and receive bit streams associated with a port. There is
one descriptor per port; therefore, the descriptor is used for both transmit and
receive directions for a single port.
NOTE:
When a port is being used in conjunction with another port —as is the case
when PORTMAP=1 or PORTMAP=2 (see Table 5-6, Global
Configuration Descriptor)—it is imperative that the unused port descriptor
be mapped identically to the used port descriptor. That is, if PORTMAP=1,
then the group 1/port 1 descriptor must be bit-for-bit identical with the
group 0/port 0 descriptor; and, the group 3/port 3 descriptor must be
bit-for-bit identical with the group 2/port 2 descriptor. In the case of
PORTMAP=2, then the group 1, 2, and 3 descriptors must be bit-for-bit
identical with the group 0/port 0 descriptor.
Table 5-12 details the Port Configuration Descriptor.
5-18
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-12. Port Configuration Descriptor
Bit
Field
Name
Value
31:10
RSVD
0
Reserved.
9
TRITX
0
Transmit Three-state Enabled. When a channel group is enabled, but a time slot within
the group is not mapped via the Time Slot Map, the transmitter three-states the output
data signal.
1
Transmit Three-State Disabled. When a channel group is enabled, but a time slot within
the group is not mapped via the Time Slot Map, the transmitter outputs a logic 1 on the
output data signal.
0
Receiver Out of Frame—Falling Edge. ROOF input sampled in on falling edge of RCLK.
1
Receiver Out of Frame—Rising Edge.
0
Receiver Frame Synchronization—Falling Edge. RSYNC input sampled in on falling
edge of RCLK.
1
Receiver Frame Synchronization—Rising Edge.
0
Receiver Data—Falling Edge. RDAT input sampled in on falling edge of RCLK.
1
Receiver Data—Rising Edge.
0
Transmitter Frame Synchronization—Falling Edge. TSYNC input sampled in on falling
edge of TCLK.
1
Transmitter Frame Synchronization—Rising Edge.
0
Transmitter Data—Falling Edge. TDAT output latched out on falling edge of TCLK.
1
Transmitter Data—Rising Edge.
8
7
6
5
4
ROOF_EDGE
RSYNC_EDGE
RDAT_EDGE
TSYNC_EDGE
TDAT_EDGE
Description
3
RSVD
0
Reserved.
2:0
PORTMD[2:0]
0
T1 Mode—24 time slots and T1 signaling.
1
E1 Mode—32 time slots and E1 signaling.
2
2xE1 Mode—64 time slots and E1 signaling.
3
4xE1 Mode—128 time slots and E1 signaling.
4
Nx64 Mode. Frame synchronization flywheel disabled. COFA detection disabled. Every
synchronization signal assertion resets time slot counter to zero.
5–7
100660E
Reserved.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.2.6 Message Length
Descriptor
Each channel group can have two separate values for maximum message length:
MAXFRM1 or MAXFRM2 (see Table 5-13). The maximum message length is
4,094 octets. The minimum message length is either 1, 3, or 5 depending on
non-FCS mode or FCS16 or FCS32 support, respectively. Each receive channel
either selects one of these message length values or disables message length
checking altogether.
The MAXSEL bit field (see Table 5-18, Channel Configuration Descriptor)
selects which, if any, register is used for received-message length checking. If
MUSYCC receives a message exceeding the allowed maximum, the current
message processing is discontinued and terminates further transfer of data to
shared memory. In addition, a Receive Buffer Status Descriptor, corresponding to
the partially received message, indicates a Long Message error condition, and an
interrupt descriptor is generated towards the host indicating the same error
condition.
NOTE:
The equation that defines maximum message length without generating a
LNG error is:
Maximum Message Length = MAXFRM – FCS where FCS = 2 bytes for
HDLC-16 protocol and FCS = 4 bytes for HDLC-32 protocol.
In the case of a short message (bit count less than 3 or 5 octets), data is not
transferred into shared memory and is discarded. In addition, an interrupt
descriptor is generated towards the host, indicating the same error condition.
Table 5-13. Message Length Descriptor
Bit
Field
Name
Value
31:28
RSVD
0
27:16
MAXFRM2[11:0]
15:12
RSVD
11:0
MAXFRM1[11:0]
5.2.2.7 Time Slot Map
5-20
Description
Reserved.
Defines a limit for the maximum number of octets allowed in a received HDLC
message.
Valid values for the register range from 3 to 4094 depending on FCS16 or
FCS32.
0
Reserved.
Defines a limit for the maximum number of octets allowed in a received HDLC
message.
Valid values for the register range from 3 to 4094 depending on FCS16 or
FCS32.
The time slot map consists of 32 time slot descriptors. One descriptor maps four
time slots. The entire map contains configuration information for 128 time slots.
The serial port does not need to support 128 time slots all the time. Any number
of time slots from 1 to 128 is supportable.
The time slot map is used when the serial port associated with a channel group
is configured in one of the channelized modes: T1, E1, 2xE1, 4xE1, or Nx64.
MUSYCC supports mapping of up to 128 time slots from a channelized bit
stream with up to 32 logical channels in each channel group.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Numerous mappings of time slots to channels are possible. Multiple time slots
can be mapped to a single channel; however, each time slot can map to only one
channel at a time. When the number of active time slots exceeds the number of
channels in a group (greater than 32 time slots), and each time slot requires a
separate channel, MUSYCC can be configured to internally connect 2 or 4
channel groups together to provide up to 64- or 128-channel support, respectively.
Two time slot maps are required for each channel group, one for transmit
functions and one for receive functions. The two maps are configured
independently. Each map consists of 128 successive 8-bit fields, each
corresponding to one time slot. The bit field includes the following information:
•
•
Time Slot Enabled/Time Slot (TSEN) Mode of Operation (64 kbps,
56 kbps, subchannel) indicator
Logical channel number (0–31) associated with time slot (CH)
For disabled time slots, modes and logical channels can be assigned, but the
information does not apply to the operation of the channel.
For enabled time slots, the valid modes of operation include the following:
•
•
•
•
64 kbps Mode: all 8 bits of time slot are assigned to one channel.
56 kbps Mode: first 7 bits of time slot are assigned to one channel. Last bit,
Most Significant Bit (MSB), is unassigned and considered disabled.
Subchannel Mode, Bit 0 Disabled: first bit, Least Significant Bit (LSB), of
time slot is unassigned. Each of the next 7 bits in time slot can be
individually enabled and independently mapped to any channel in a
channel group.
Subchannel Mode, Bit 0 Enabled: first bit (LSB) of time slot is always
enabled and assigned to a channel in a channel group. Each of the next
7 bits in time slot can be individually enabled and independently mapped
to any channel in a channel group.
The logical channel number represents the channel in the channel group
handling the bit stream from the time slot or slots assigned to it. The value of the
channel number ranges from 0–31.
100660E
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-14 lists the time slot descriptor location and byte offset. Table 5-15
lists the value and description of each time slot descriptor.
Table 5-14. Transmit or Receive Time Slot Map
Time Slot Descriptor Relative Location
Byte Offset
MSB
LSB
00h
TS03
TS02
TS01
TS00
...
...
...
...
...
1Ch
TS31
TS30
TS29
TS28
...
...
...
...
...
3Ch
TS63
TS62
TS61
TS60
...
...
...
...
...
5Ch
TS95
TS94
TS93
TS92
...
...
...
...
...
7Ch
TS127
TS126
TS125
TS124
Accessing the Time Slot Map within MUSYCC requires that a serial line
clock be present at the serial interface. If a clock is not present, writes are ignored,
and reads return all 1s.
5-22
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
The host can read and write the Receive Time Slot Map information from
within MUSYCC; however, the host can only write Transmit Time Slot Map into
MUSYCC. The transmit maps are stored in write-only registers. Reading transmit
maps results in all 1s being returned.
Table 5-15. Time Slot Descriptor
Bit
Field
Name
Value
31:29
TSEN3[2:0]
0
1–3
5
Time Slot Enabled. 56 kbps mode.
6
Time Slot Enabled. Subchannel mode w/o first bit.
7
Time Slot Enabled. Subchannel mode w/ first bit.
0–31
23:21
TSEN2[2:0]
0
1–3
Channel number assigned to this time slot.
Time Slot Disabled. Default.
Reserved.
4
Time Slot Enabled. 64 kbps mode.
5
Time Slot Enabled. 56 kbps mode.
6
Time Slot Enabled. Subchannel mode w/o first bit.
7
Time Slot Enabled. Subchannel mode w/ first bit.
20:16
CH2[4:0]
0–31
15:13
TSEN1[2:0]
0
1–3
Channel number assigned to this time slot.
Time Slot Disabled. Default.
Reserved.
4
Time Slot Enabled. 64 kbps mode.
5
Time Slot Enabled. 56 kbps mode.
6
Time Slot Enabled. Subchannel mode w/o first bit.
7
Time Slot Enabled. Subchannel mode w/ first bit.
12:8
CH1[4:0]
0–31
7:5
TSEN0[2:0]
0
1–3
100660E
Reserved.
Time Slot Enabled. 64 kbps mode.
CH3[4:0]
CH0[4:0]
Time Slot Disabled. Default.
4
28:24
4:0
Description
Channel number assigned to this time slot.
Time Slot Disabled. Default.
Reserved.
4
Time Slot Enabled. 64 kbps mode.
5
Time Slot Enabled. 56 kbps mode.
6
Time Slot Enabled. Subchannel mode w/o first bit.
7
Time Slot Enabled. Subchannel mode w/ first bit.
0–31
Channel number assigned to this time slot.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.2.8 Subchannel Map
To provide the subchanneling feature, MUSYCC shares the time slot mapping
function between a Time Slot Map and a Subchannel Map. The transmit and
receive functions each have a separate pair of maps.
The Time Slot Map indicates if the time slot is enabled and configured for
subchanneling. The TSEN bit field in the Time Slot Descriptor specifies the
mode of operation for the time slot. If TSEN = 6, the time slot is in subchannel
mode with bit 0 disabled. If TSEN = 7, the time slot is in subchannel mode with
bit 0 enabled and mapped to the channel specified in the CH bit field in the same
Time Slot Descriptor. The CHx bit field is also used in the treatment of the
remaining 7 bits in the time slot, specifically as part of an index into Subchannel
Map. The Time Slot Map always manages (disables or enables or maps) bit 0 of
the time slot. The Subchannel Map configures each of the remaining 7 bits of a
time slot.
The CHx bit field (0–31) from the Time Slot Descriptor is linked with the bit
number (1–7) of the time slot being processed to form an 8-bit index (0–255) into
the Subchannel Map for each bit number. The Subchannel Map associates each
bit of a time slot to a channel.
For a time slot configured for subchannel mode, MUSYCC considers each bit
of that time slot independently of any other bit in the same time slot. Any bit can
be enabled or disabled. The time slot is considered to consist of 8 individual
8 kbps bit streams, or subchannels. The subchannels can remain separated or be
concatenated to provide one or more subchannels running at bit rates between
8 kbps and 64 kbps, inclusive, in multiple of 8 kbps.
Note the following special cases for subchannel map assignments:
•
•
•
Bit 0 is always disabled or enabled/mapped by the Time Slot Map;
therefore, configuring the Subchannel Map for bit 0 is not required.
Assigning the same channel number for all bits (including bit 0) is
equivalent to disabling the subchanneling feature and treating the time slot
as if in 64 kbps mode.
Disabling all bits in subchannel mode is equivalent to disabling the time
slot using the Time Slot Map.
The Subchannel Map can map bits 1–7 from each time slot to any of
32 channels in a channel group. The map for bit 0 is allocated, but unused (bit 0 is
mapped by the time slot map). The Subchannel Map consists of 256 descriptors
representing 32 channels and 8 bits per channel. Two subchannel descriptors
(2 dwords) are required to describe the treatment of 8 bits of one channel. The
first dword describes the treatment of the lower 4 bits, and the second dword
describes the treatment of the upper 4 bits. Table 5-16 lists the subchannel
descriptor location and byte offset. Table 5-17 lists the value and description of
each subchannel descriptor.
5-24
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-16. Transmit or Receive Subchannel Map
Byte Offset
MSB
LSB
00h
Ch0, Bit 3
Ch0, Bit 2
Ch0, Bit 1
Unused
04h
Ch0, Bit 7
Ch0, Bit 6
Ch0, Bit 5
Ch0, Bit 4
08h
Ch1, Bit 3
Ch1, Bit 2
Ch1, Bit 1
Unused
0Ch
Ch1, Bit 7
Ch1, Bit 6
Ch1, Bit 5
Ch1, Bit 4
...
....
....
....
...
...
....
....
....
...
F8h
Ch31, Bit 3
Ch31, Bit 2
Ch31, Bit 1
Unused
FCh
Ch31, Bit 7
Ch31, Bit 6
Ch31, Bit 5
Ch31, Bit 4
Table 5-17. Subchannel Descriptor
Bit Field
Name
Value
Description
31
BITEN3/7
0
Bit disabled.
1
Bit enabled.
Reserved.
30:29
RSVD
0
28:24
CH3[4:0]
0–31
23
BITEN2/6
0
Bit disabled.
1
Bit enabled.
Reserved.
Channel number assigned to this bit.
22:21
RSVD
0
20:16
CH2[4:0]
0–31
15
BITEN1/5
0
Bit disabled.
1
Bit enabled.
Reserved.
Channel number assigned to this bit.
14:13
RSVD
0
12:8
CH1[4:0]
0–31
7
BITEN0/3
0
Bit disabled.
1
Bit enabled.
Reserved.
6:5
RSVD
0
4:0
CH0[4:0]
0–31
Channel number assigned to this bit.
Channel number assigned to this bit.
To enable the subchanneling feature, both the Time Slot Map and the
Subchannel Map must be copied into MUSYCC’s internal registers because it is
from here time slot-to-channel mapping and channel-to-subchannel mapping is
decoded. The host can instruct MUSYCC to read in the maps from shared
memory by issuing the appropriate service request; otherwise, the host must
perform multiple direct writes into MUSYCC’s internal registers by appropriately
addressing PCI access cycles for MUSYCC.
100660E
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Accessing the Time Slot Map or Subchannel Map within MUSYCC requires
that a serial line clock be present at the serial interface. If a clock is not present,
writes are ignored, and reads return all 1s.
The host can read and write the Receive Time Slot Map from within
MUSYCC; however the host can only write the Transmit Time Slot Map into
MUSYCC. The transmit maps are stored in write-only registers. Reading transmit
maps results in all 1s being returned.
The host can read and write the Receive Subchannel Map from within
MUSYCC; however, the host can only write the Transmit Subchannel Map into
MUSYCC. The transmit maps are stored in write-only registers. Reading the
transmit map results in all 1s being returned.
5.2.3 Channel Level Descriptors
The channel level descriptors contain information necessary to configure channel
registers.
5.2.3.1 Channel
Configuration Descriptor
The Channel Configuration Descriptor configures aspects of the channel
common to all messages passing through the channel. One descriptor exists for
each logical channel direction.
Table 5-18 lists the values and description of each channel configuration
descriptor.
Table 5-18. Channel Configuration Descriptor (1 of 3)
Bit
Field
Name
Value
31
PADJ
0
Pad Count Adjustment disabled. No adjustment is made to the value of
PADCNT if Zero Insertions is detected.
1
Pad Count Adjustment enabled. The value of PADCNT is reduced if Zero
Insertions is detected. This adjustment is required for rate adaptive applications
such as ITU-T Recommendation V.120.
Reserved
Description
30
RSVD
0
29:24
BUFFLOC[5:0]
00h–3Fh
23
INV
0
Data Inversion disabled. All data bits in message are not inverted between
shared memory and MUSYCC.
22
RSVD
0
Reserved.
21:16
BUFFLEN[5:0]
00h–3Fh
Internal Data Buffer Length. Number of internal FIFO data buffer locations
allocated to this channel and direction equals 2 x (BUFFLEN+1) dwords.
15
EOPI
0
End Of Padfill Interrupt disabled. Transmit Only. After outputting last padfill
code, do not generate interrupt indicating condition.
1
End of Padfill Interrupt enabled.
5-26
Channel Buffer Location Index. Starting location of internal FIFO data buffer for
this channel and direction.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-18. Channel Configuration Descriptor (2 of 3)
Bit
Field
Name
Value
14:12
PROTOCOL[2:0]
0
TRANSPARENT
1
SS7-HDLC-FCS16
2
HDLC-FCS16
3
HDLC-FCS32
4–7
11:10
9
8
7
6
5
4
100660E
MAXSEL[1:0]
FCS
MSKSUERR
MSKSINC
MSKSDEC
MSKSFILT
MSKIDLE
Description
Reserved.
0
Message Length—Disable message length check.
1
Message Length—Use Register 1. Use MAXFRM1 bit field in the message
length descriptor for maximum receive message length limit.
2
Message Length—Use Register 2. Use MAXFRM2 bit field in the message
length descriptor for maximum receive message length limit.
3
Reserved
0
FCS Transfer Normal. For receive, do not transfer received FCS into shared
memory along with data message. For transmit, do transmit calculated FCS out
serial port after last bit in last data buffer has been transmitted.
1
FCS=1. Non FSC Mode. For receive, transfer received FCS 31 into shared
memory along with data message; do not transmit calculated FCS out of serial
port.
In Non-FCS Mode, a SHT message detection is disabled. Any number of bytes
can be transmitted and received within any single message, including message
length of only one byte.
0
SUERR Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, Signal
Unit Error Rate Monitor function generates interrupt when signal unit error
count crosses signal unit error threshold.
1
SUERR Interrupt disabled.
0
SINC Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, SUERM
function generates interrupt when signal unit error count increments.
1
SINC Interrupt disabled.
0
SDEC Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, SUERM
function generates interrupt when signal unit error count decrements.
1
SDEC Interrupt disabled.
0
SFILT Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, interrupt
generated when two consecutive received messages are found to be identical.
Second message discarded.
1
SFILT Interrupt disabled. For SS7-HDLC-FCS16 mode, interrupt is not
generated when two consecutive received messages are found to be identical.
Second message discarded.
0
CHABT, CHIC, SHT Interrupt enabled. Receive only. When receiver detects
change to abort code, change to idle code, or too-short message, this bit
generates interrupt to indicate condition.
1
CHABT, CHIC, SHT Interrupt disabled.
Conexant
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Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Table 5-18. Channel Configuration Descriptor (2 of 3)
Bit
Field
Name
Value
14:12
PROTOCOL[2:0]
0
TRANSPARENT
1
SS7-HDLC-FCS16
2
HDLC-FCS16
3
HDLC-FCS32
4–7
11:10
9
8
7
6
5
4
5-28
MAXSEL[1:0]
FCS
MSKSUERR
MSKSINC
MSKSDEC
MSKSFILT
MSKIDLE
Description
Reserved.
0
Message Length—Disable message length check.
1
Message Length—Use Register 1. Use MAXFRM1 bit field in the message
length descriptor for maximum receive message length limit.
2
Message Length—Use Register 2. Use MAXFRM2 bit field in the message
length descriptor for maximum receive message length limit.
3
Reserved
0
FCS Transfer Normal. For receive, do not transfer received FCS into shared
memory along with data message. For transmit, do transmit calculated FCS out
serial port after last bit in last data buffer has been transmitted.
1
FCS=1. Non FSC Mode. For receive, transfer received FCS 31 into shared
memory along with data message; do not transmit calculated FCS out of serial
port.
In Non-FCS Mode, a SHT message detection is disabled. Any number of bytes
can be transmitted and received within any single message, including message
length of only one byte.
0
SUERR Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, Signal
Unit Error Rate Monitor function generates interrupt when signal unit error
count crosses signal unit error threshold.
1
SUERR Interrupt disabled.
0
SINC Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, SUERM
function generates interrupt when signal unit error count increments.
1
SINC Interrupt disabled.
0
SDEC Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, SUERM
function generates interrupt when signal unit error count decrements.
1
SDEC Interrupt disabled.
0
SFILT Interrupt enabled. Receive only. For SS7-HDLC-FCS16 mode, interrupt
generated when two consecutive received messages are found to be identical.
Second message discarded.
1
SFILT Interrupt disabled. For SS7-HDLC-FCS16 mode, interrupt is not
generated when two consecutive received messages are found to be identical.
Second message discarded.
0
CHABT, CHIC, SHT Interrupt enabled. Receive only. When receiver detects
change to abort code, change to idle code, or too-short message, this bit
generates interrupt to indicate condition.
1
CHABT, CHIC, SHT Interrupt disabled.
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5.2 Descriptors
Table 5-18. Channel Configuration Descriptor (3 of 3)
Bit
Field
Name
Value
Description
3
MSKMSG
0
LNG, FCS, ALIGN, ABT Interrupt enabled. Receive only. When receiver detects
too-long message, FCS error, message alignment error, or abort condition, this
bit generates interrupt to indicate condition.
1
In order for MSKMSG=1 to disable all interrupts (LNG, FCS, ALIGN) the
MSKEOM must be set (i.e., 1).
0
EOM Interrupt enabled. Receive and Transmit. Interrupt generated when end of
message detected.
1
EOM Interrupt disabled.
0
BUFF—Interrupts enabled. Receive and Transmit. Interrupt generated when
transmitter underflow buffer or receiver overflows buffer internally to MUSYCC.
ONR—Interrupts enabled. Receive and Transmit. Interrupt generated where
message pointer/descriptor is not available to MUSYCC where is expected.
(Refer to Figure 5-31, Interrupt Descriptor.)
1
BUFF—Interrupts disabled. ONR—Interrupts disabled.
0
Reserved.
2
1
0
MSKEOM
MSKBUFF
RSVD
5.2.4 Message Level Descriptor
One message descriptor defines one data buffer where all or part of a message is
stored in shared memory. By linking message descriptors, numerous data buffers
are linked to support high-speed data links or large messages spread across a
number of smaller data buffers.
Depending on the transmission and reception rate of individual channels, the
numbers and sizes of message buffers can vary between channels and
applications. For high-speed lines, more and larger buffers can be used to provide
ample data storage while the host processes each message in the list of messages.
For low-speed lines, fewer and smaller buffers can be used as the host may be able
to process each message faster and the need to store messages is lessened.
Multiple smaller data buffers can be linked using message descriptors to store
one large message. In utilizing multiple buffers, the importance of keeping the
sequence of data buffers in order is obvious.
MUSYCC’s operation allows for the following:
•
•
•
•
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Multiple buffer lists
Multiple and variable size buffers within a buffer list
Multiple buffers storing a single message
Sequencing of individual data buffers for a multi-buffer message
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5.2 Descriptors
A message descriptor is designed to be usable by both the transmit and receive
functions in MUSYCC. In providing this symmetry, a mechanism known as
self-servicing buffers is available, which allows the reuse of a single descriptor
for both the transmit and receive portions of a channel, and is designed for
diagnostics and loopback capabilities. Table 5-19 lists the message descriptor
details.
Table 5-19. Message Descriptor
Byte Offset
Field Name
Bytes
00h
Buffer Descriptor (Host Writes)
Buffer Status Descriptor (MUSYCC Writes)
1
4
04h
Data Pointer
1
4
08h
Next Pointer
1
4
3
12
TOTAL
5.2.4.1 Using Message
Descriptors
5-30
dwords
MUSYCC checks data from a message descriptor before processing the
associated data buffer. When a data buffer is completely processed (either
transmitted or received), MUSYCC overwrites the buffer descriptor field (the
first dword in a message descriptor) with a buffer status descriptor.
The buffer status descriptor specifies the number of bytes transferred, an end
of message indicator, and a buffer owner-bit indicator that assigns control of
associated buffers back to the host.
The owner bit transfers control of a data buffer between MUSYCC and the
host. The message descriptor can be assigned before an associated data buffer is
allocated in memory. In this case, MUSYCC polls the contents of the buffer
descriptor until the host grants ownership of a data buffer to MUSYCC. After
MUSYCC processes the data buffer, it grants the ownership back to the host.
The owner bit prevents MUSYCC from processing the same buffer twice
without intervention from the host. If MUSYCC detects an opening flag of a
received message, but does not have ownership of the current data buffer (via the
current message descriptor), an interrupt is sent to the host indicating that
MUSYCC needed a data buffer and did not have access to one.
The host can append additional information beyond the end of a data buffer as
long as the longest message length can be fitted first into the data buffer. In the
case of additional information, MUSYCC would not know about the information,
nor would it ever read from or write to that space.
For simplicity, the message level descriptions that follow are made in
reference to one channel. Each channel is serviced independently of other
channels, and separate descriptor lists are maintained for each supported channel.
Similarly, the transmit and receive sections of a channel service that the
descriptor lists identically and separate descriptor lists are maintained for each
section. Also, the size of data fields in the descriptors are identical; however, the
layout of fields between receive and transmit descriptors are different.
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5.2 Descriptors
5.2.4.2 Note for
Interrupt Driven Drivers
An interrupt from MUSYCC does not imply that MUSYCC read a buffer status
descriptor and made it host-owned.
As mentioned in Note (2) in Table 5-31, the occurrence of a MUSYCC
interrupt and a buffer status descriptor update are not time correlated. The delay
of the buffer status descriptor update is a maximum of 2 HDLC frames after the
interrupt.
The driver must read the owner field to confirm its ownership before writing a
new buffer status descriptor. If the driver receives an interrupt and does not detect
a host-owned buffer, it should wait a minimum of 2 HDLC frames before
signaling an abnormal condition.
The requirement to check the buffer status descriptor is applicable only when
buffer status descriptor updates are enabled (INHRBSD = 0).
5.2.4.3 Head Pointer
The head pointer points to the first message descriptor in a list of descriptors
assigned to a channel’s transmitter or receiver.
A head pointer allows the host to specify a new list of descriptors to use for
channel processing. This mechanism can be used after a reset to kick-start or
reactivate channel processing which has completely processed the current list of
descriptors.
A head pointer also allows the host to generate a new list of descriptors in
memory before performing a list transition; that is, while MUSYCC processes
data in one list, the host can process data in a separate list, and, when appropriate,
can switch the lists.
Table 5-20 lists the head pointers and their descriptions.
Table 5-20. Head Pointer
Bit
Field
Name
31:2
HEADPTR[29:0]
1:0
HEADPTR[1:0]
5.2.4.4 Message Pointer
Value
Description
These 30 bits are appended with 00b to form a dword-aligned 32-bit address. This
address points to the first Message Descriptor in a list of descriptors.
0
Ensures dword alignment.
The message pointer points to the current message descriptor being serviced. This
pointer is maintained in a fixed memory location relative to a Group Base Pointer
in shared memory.
Table 5-21 lists the message pointers and their descriptions.
Table 5-21. Message Pointer
Bit
Field
Name
31:2
MSGPTR[29:0]
1:0
MSGPTR[1:0]
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Value
Description
These 30 bits are appended with 00b to form a dword-aligned 32-bit address. This
word pointer points to the first dword of a Message Descriptor.
0
Ensures dword alignment.
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5.2 Descriptors
5.2.4.5 Message
Descriptor
The Message Descriptor is pointed to by the Message Pointer and the Head
Pointer and is maintained in a variable location in shared memory. A Message
Descriptor includes the following fields:
•
•
•
•
5.2.4.6 Buffer
Descriptor
Buffer Descriptor (when host writes)
Buffer Status Descriptor (when MUSYCC writes)
Data Buffer Pointer
Next Descriptor Pointer
The Buffer Descriptor is the first dword of a Message Descriptor after the host
has prepared the data structures in memory. All Buffer Descriptors include the
following fields:
•
•
•
•
Owner Indicator Bit (OWNER)
No Poll/Poll Indicator (NP)
End of Buffer Interrupt Enable (EOBI)
Buffer Length (BLEN)
The OWNER bit is a generic term for any descriptor. In a Transmit Buffer
Descriptor it is called MUSYCC; in a Receive Buffer Descriptor it is called host.
The names are different to indicate that the active sense of the owner bit is
different between transmit and receive functions.
In addition to the above list of fields, Transmit Buffer Descriptors also include
the following fields:
•
•
•
•
•
End of Message Indicator (EOM)
Idle Code Selection (IC)
Pad Enable (PADEN)
Pad Count (PADCNT)
Repeat Packet Enable (REPEAT)
IC, PADEN, PADCNT, and REPEAT are valid only when EOM = 1.
5-32
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5.2 Descriptors
Tables 5-22 and 5-23 list the transmit and receive buffer descriptors and
definitions.
Table 5-22. Transmit Buffer Descriptor
Bit
Field
Name
Value
Description
31
OWNER
0
HOST Owns Buffer. HDLC channel remains in idle mode while polling this bit periodically (if
NP = 0) until host relinquishes control to MUSYCC by setting OWNER = 1. In transparent
mode the channel is deactivated.
1
MUSYCC Owns Buffer. Continue processing data buffer normally.
0
Poll Enabled. If OWNER = 0, host-owned, MUSYCC polls the message descriptor
periodically while in idle mode until OWNER = 1.
1
Poll Disabled. If OWNER = 0, then waits for a Channel Activate or Jump Service Request
from host.
0
Data Buffer w/o End of Message.
1
Data Buffer w/ End of Message.
0
End of Buffer Interrupt Disabled. When no more data can be taken from or put into a data
buffer, an EOB interrupt is not generated.
1
End of Buffer Interrupt Enabled.
0
Reserved.
0
Idle Code Select – 7Eh
1
Idle Code Select – FFh
2
Idle Code Select – 00h
3
Reserved.
0
Pad Fill Disabled. One shared opening/closing flag (7Eh) is inserted before sending next
message.
1
Pad Fill Enabled. Also, see PADCNT bit field.
30
29
28
NP
EOM
EOBI
27
26:25
24
IC[1:0]
PADEN
23:16
PADCNT[7:0]
15
REPEAT
14
RSVD
13:0
BLEN[13:0]
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Pad Count. When PADEN = 1, PADCNT indicates the minimum number of idle codes to be
inserted between the closing flags and the next opening flag (7Eh). If PADCNT = 2 and
IC = 1, for example, MUSYCC outputs the bit pattern 7Eh..FFh..FFh..7Eh. There is no
indication by MUSYCC if more than PADCNT number of idle codes are inserted.
0
Repeat message transmission disabled.
1
Repeat message transmission enabled.
0
Reserved.
Buffer Length. The number of octets in data buffer to be transmitted. In general, this would
equal the allocated buffer size.
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5.2 Descriptors
Table 5-23. Receive Buffer Descriptor
Bit
Field
Name
Value
31
OWNER
0
MUSYCC Owns Buffer. Continue processing data buffer normally.
1
HOST Owns Buffer. Channel is to remain in idle mode while polling this bit periodically
(if NP = 0) until host relinquishes control to MUSYCC by setting OWNER = 0.
In transparent mode the channel is deactivated.
0
Poll Enabled. If OWNER = 1, host-owned, MUSYCC polls message descriptor
periodically until OWNER = 0.
1
Poll Disabled. If OWNER = 1 then wait for a Channel Activate Service Request from
host.
30
NP
Description
29
RSVD
0
Reserved.
28
EOBI
0
End of Buffer Interrupt Disabled. When more data cannot be taken from or put into a
data buffer, an EOB interrupt is not generated.
1
End of Buffer Interrupt enabled.
0
Reserved.
27:14
RSVD
13:0
BLEN[13:0]
5.2.4.7 Buffer Status
Descriptor
Buffer Length. Actual number of received data octets might be less than this. This
number indicates how many will fit into data buffer. The buffer length should not
exceed 8 k.
The Buffer Status Descriptor contains status information regarding data buffer
servicing. If configured to do so, MUSYCC writes a Buffer Status Descriptor
over a Buffer Descriptor. This descriptor includes the following fields:
•
•
•
Owner Indicator Bit (OWNER)
End of Message Indicator (EOM)
Data Length (DLEN)
In addition to the fields, a Receive Buffer Status Descriptor also includes the
Error Status (ERROR) bit field.
Buffer Status Descriptors are designed to work with Buffer Descriptors. This
allows a self-servicing buffer mechanism where a transmit channel will empty a
list of data buffers immediately after a receive channel fills those buffers, all
without host intervention. The value for the OWNER bit field in the transmit
buffer is opposite of the value of the OWNER bit field in the receive buffer
descriptor.
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5.2 Descriptors
Tables 5-24 and 5-25 list the transmit and receive buffer status descriptors and
their descriptions.
Table 5-24. Transmit Buffer Status Descriptor
Bit
Field
Name
Value
Description
31
OWNER
0
Host Owns Buffer. MUSYCC has relinquished control of buffer back to host. MUSYCC
is done processing buffer.
1
MUSYCC Owns Buffer. Until MUSYCC relinquishes control, the data in this descriptor
is being used by MUSYCC.
30
RSVD
0
Reserved.
29
EOM
0
End of Message Indicator. Copied from Transmit Buffer Descriptor.
1
End of Message Indicator. Copied from Transmit Buffer Descriptor.
0
Reserved.
28:14
RSVD
13:0
BLEN[13:0]
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Buffer Length. The number of octets from data buffer transmitted. In general this
would equal the allocated buffer size.
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5.2 Descriptors
Table 5-25. Receive Buffer Status Descriptor
Bit
Field
Name
Value
Description
31
OWNER
0
MUSYCC Owns Buffer. Until MUSYCC relinquishes control, the data in this descriptor
is being used by MUSYCC.
1
Host Owns Buffer. MUSYCC has relinquished control of buffer back to host. MUSYCC
is done processing buffer.
30
RSVD
0
Reserved.
29
EOM
0
End of Message Indicator. The last octet for this message is not in this buffer.
1
End of Message indicator. The last octet for this data message is in this buffer either
because a valid closing flag (7Eh) was detected or the receiver terminated due to an
error condition.
28:20
RSVD
0
Reserved.
19:16
ERROR[3:0]
0
OK: No error detected in this receive buffer.
1
BUFF: Buffer Error. Data is lost. For receive: Internal data buffer overflow.
2
COFA: Change Of Frame Alignment. RSYNC signal is misaligned with the flywheel in
the serial interface.
3–7
Reserved.
8
OOF: Out of Frame. ROOF signal is asserted.
9
FCS: Frame Check Sequence Error. Received HDLC frame is terminated with proper
7Eh flag, but computed FCS does not match received FCS.
10
ALIGN: Octet Alignment Error. Message payload size, after zero extraction, is not a
multiple of 8 bits. This error takes precedence over an FCS error.
11
ABT: Abort Flag Termination. Received message is terminated with abort sequence,
seven sequential 1s, instead of a closing flag (7Eh).
12
LNG: Long Message. Message payload size greater than selected limit was received.
Message processing is terminated and transfer to shared memory is discontinued.
Channel resumes scanning for HDLC flags or idle codes.
13–15
Reserved.
15:14
RSVD
0
Reserved.
13:0
DLEN[13:0]
—
Received Octets.
5-36
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5.2.4.8 Next Message
Pointer
5.2 Descriptors
The Next Message Pointer is a 32-bit dword-aligned address pointing to the first
dword of a Message Descriptor which is next in a list of descriptors.
Table 5-26 lists the Next Descriptor Pointer and its description. The last Next
Message Pointer should point to the first Message Descriptor and not to itself.
Table 5-26. Next Descriptor Pointer
Bit
Field
Name
31:2
NEXTPTR[29:0]
1:0
NEXTPTR[1:0]
5.2.4.9 Data Buffer
Pointer
Value
Description
These 30 bits are appended with 00b to form a dword-aligned 32-bit address.
This address points to the next message descriptor in the list.
0
Ensures dword alignment.
The Data Buffer Pointer is a 32-bit address to the first byte of a data message in
shared memory. This pointer does not have to be word- or dword-aligned.
Table 5-27 lists the Data Buffer Pointer and its description.
Table 5-27. Data Buffer Pointer
Bit
Field
Name
31:0
DATAPTR[31:0]
5.2.4.10 Message
Descriptor Handling
Value
Description
The 32-bit address in this descriptor serves as a byte pointer to the first octet of a
data buffer.
The bit fields Inhibit Buffer Status Descriptor (INHTBSD for transmitters or
INHRBSD for receivers) in the Group Configuration Descriptor specify whether
or not MUSYCC writes a Buffer Status Descriptor to shared memory after the
end of the current message has been detected.
If INHTBSD/INHRBSD is set to 0, MUSYCC:
Assumes the Message Pointer points to the current Message Descriptor.
Overwrites the Buffer Descriptor field with the Buffer Status Descriptor
field.
3. Fetches the next Message Pointer from the descriptor.
4. Reads the next Message Descriptor.
5. Writes the pointer to the new descriptor into the Message Pointer in shared
memory.
1.
2.
If INHTBSD/INHRBSD is set to 1, MUSYCC:
1.
2.
3.
100660E
Assumes the Message Pointer points to the next Message Descriptor.
Reads the next Message Descriptor.
Writes the Next Message Pointer from the descriptor into the Message
Pointer in shared memory.
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5.2 Descriptors
5.2.5 Interrupt Level Descriptors
MUSYCC generates interrupts for a variety of reasons. Interrupts are events or
errors detected by MUSYCC during bit-level processing of incoming serial data
streams. Interrupts are generated by MUSYCC and forwarded to the host for
servicing. Individual types of interrupts can be masked from being generated by
setting the appropriate interrupt mask or interrupt disable bit fields in various
descriptors. The interrupt mechanism, each individual interrupt, and interrupt
controlling mechanisms are discussed in this section.
5.2.5.1 Interrupt Queue
Descriptor
MUSYCC employs a single Interrupt Queue Descriptor to communicate interrupt
information to the host. This descriptor is stored in MUSYCC in an internal
register. The descriptor in this register space stores the location and size of an
interrupt queue in shared memory. MUSYCC requires this information to transfer
interrupt descriptors it generates to shared memory for the host to use. MUSYCC
writes Interrupt Descriptors directly into the shared memory queue using PCI bus
master mode. MUSYCC’s PCI interface must be configured to allow bus
mastering.
The Interrupt Queue Descriptor is initialized by the host issuing a service
request to MUSYCC to read of a copy of the Interrupt Queue Descriptor from
shared memory. Another method of initialization is for the host to directly write
the information into the appropriate register space within MUSYCC.
Tables 5-28 through 5-30 list the details of the Interrupt Queue Descriptor.
Table 5-28. Interrupt Queue Descriptor
Byte Offset
Field Name
dwords
Octets
00h
Interrupt Queue Pointer
1
4
04h
Interrupt Queue Length
1
4
2
8
TOTAL
Table 5-29. Interrupt Queue Pointer
Bit
Field
Name
31:2
IQPTR[30:0]
1:0
IQPTR[1:0]
Value
Description
These 30 bits are appended with 00b to form a dword-aligned 32-bit address. This
address points to the first word of the Interrupt Queue buffer.
0
Ensures dword alignment.
Table 5-30. Interrupt Queue Length
Bit
Field
Name
Value
31:15
RSVD
0
14:0
IQLEN[14:0]
5-38
Description
Reserved.
This 15-bit number specifies the length of the Interrupt Queue buffer in dwords. The
maximum size for an interrupt queue is 32,768 dwords. This is a 0-based number. A
value of 1 indicates the queue length is 2 descriptors long, the required minimum.
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5.2.5.2 Interrupt
Descriptor
5.2 Descriptors
The Interrupt Descriptor describes the format of data transferred into the queue.
This 32-bit word includes bit fields for the following:
•
•
•
•
Identifying the interrupt source from within MUSYCC. Channel group
number (0–8), channel number (0–31), and direction (receive or transmit)
are provided. There are 256 possible channel sources.
Events assisting the host in synchronizing channel activities.
Errors and unexpected conditions resulting in lost data, discontinued
message processing, or prevented successful completion of a service
request.
Number of bytes transferred to or from shared memory when a memory
buffer has been completely processed.
All interrupts are associated with a channel group, channel number, and
direction of the channel with the following exceptions:
When an OOF or COFA condition is detected on a serial port, only one
interrupt is generated for the entire group until the condition is cleared and
the condition reoccurs. The group is identified by the GRP field, and the
direction is identified by the DIR field. The CH field is the channel
number currently being serviced when this condition is detected.
2. The ILOST interrupt bit indicates that one or more interrupt was lost
internally due to a lack of internal queuing space. This occurs when
MUSYCC generates more interrupt descriptors than can be stored in the
Interrupt Queue in shared memory. The latency of host processing of the
Interrupt Queue can also be a factor. This condition is conveyed by
MUSYCC overwriting the ILOST bit field in the last interrupt descriptor
in an internal queue prior to being transferred to shared memory. The bit
field is not specific to or associated with the interrupt descriptor being
overwritten. Only one bit is overwritten, and the integrity of the original
descriptor is maintained.
3. The PERR interrupt bit indicates that MUSYCC detected a parity error
during a PCI access cycle. This condition is conveyed by MUSYCC
overwriting the PERR bit field in the last interrupt descriptor in an internal
queue prior to being transferred to shared memory. The bit field is not
specific to or associated with the interrupt descriptor being overwritten.
Only one bit is overwritten and the integrity of the original descriptor is
maintained.
1.
Interrupt descriptors can convey certain combinations of events and errors,
but no more than one event and one error. Because multiple information can be
conveyed via a single interrupt descriptor, always look at both the event and error
fields when servicing interrupt descriptors. Following is a list of possible
combinations of events and errors.
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5.2 Descriptors
Items Issued Separately
Items That Can Combine
The following items are issued separately in their own interrupt descriptors:
•
Events:
– SACK
– EOP
– CHABT
– CHIC
– FREC
– SINC
– SDEC
– SFILT
•
Errors:
– PERR
– PROT
– SUERR
In the list below, a single event can combine with a single error within the same
interrupt descriptor:
•
Events:
– EOB
– EOM
•
Errors:
– BUFF
– COFA
– ONR
– OOF
– FCS
– ALIGN
– ABT
– LNG
– SHT
The ILOST error is always piggybacked onto an existing interrupt descriptor
which can have an event, an error, or both bit fields set.
Table 5-31 lists details and descriptions of the interrupt descriptor.
Section 6.4.8 and 6.4.9 provide detailed explanations of the reasons, effects,
and recovery actions for events and errors.
Errors reported in the buffer status descriptor are also reported in the interrupt
descriptor. The occurrence in shared memory of a buffer status descriptor and the
interrupt descriptor conveying the same error condition is indeterminate. The
occurrence of an interrupt does not imply host ownership of the buffer status
descriptor. The host must always confirm ownership of the buffer status
descriptor before overwriting it.
5-40
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5.2 Descriptors
Maskable
Direction
Channel
Bit
Field
Field
Name
Value
31
DIR
0
Receive.
1
Transmit.
Description
Rx
Tx
Interrupt
Name
Group
Table 5-31. Interrupt Descriptor (1 of 4)
30:29
GRP[1:0]
0–3
Least significant 2 bits of the Group Number. The most
significant group number is defined in bit 14.
28:24
CH[4:0]
0–31
Channel Number.
23:20
EVENT[3:0]
0
NONE
V
V
V
V
No event to report in this interrupt.
1
SACK
V
V
V
V
Service Request Acknowledge. Generated at conclusion of
service request which was processed successfully. In case
of an error as a result of a service request being executed,
other interrupts can be generated; for example, PERR.
2
EOB
V
V
V
V
V
End of Buffer. Generated when current data buffer has been
completely processed, and EOBI bit field in associated
Transmit Buffer Descriptor or Receive Buffer Descriptor is
set. Also, EOB interrupt reports the correct number of
transmitted bytes in BLEN field.(1)
3
EOM
V
V
V
V
V
End of Message. Generated when data buffer which was
just processed contained last octet of message. “Transmit
EOM” means the last bit of data (not including FCS or
closing FLAG) has been output on the serial port, and
“Receive EOM” means the entire HDLC frame (including
FCS and closing FLAG) has been written to shared memory
buffer.(1)
4
EOP
V
V
V
V
V
End of Padfill. Generated when the pad-count is enabled
with non-0 value in a transmit channel, and last idle code
octet is sent. This interrupt is conditioned on the end of
padfill-enabled bit being set in the Transmit Channel
Configuration Descriptor.
5
CHABT
V
V
V
V
Change To Abort Code. Generated when a received pad fill
code changes from 7Eh to FFh – abort code.
6
CHIC
V
V
V
V
Change to Idle Code. Generated when a received pad fill
code changes from FFh to 7Eh – idle code.
7
FREC
V
V
V
V
Frame Recovery. Generated when serial port transitions
from Out-of-Frame (OOF) back to in-frame.
8
SINC
V
V
V
V
SS7 SUERM Octet Count Increment. Generated when in
SS7 mode and Signal Unit Error Rate Monitor counter
increments.
9
SDEC
V
V
V
V
SS7 SUERM Octet Count Decrement. Generated when in
SS7 mode and Signal Unit Error Rate Monitor counter
decrements.
10
SFILT
V
V
V
V
SS7 Filtered Message. Generated when in SS7 mode and
just-received message is identical to one previous
message. The current message is not written to shared
memory.
23:20
EVENT[3:0]
11-15
100660E
Reserved.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Bit
Field
Field
Name
Value
Interrupt
Name
Group
Channel
Tx
Rx
Maskable
Direction
Table 5-31. Interrupt Descriptor (2 of 4)
19:16
ERROR[3:0]
0
NONE
V
V
V
V
1
BUFF(2)
V
V
V
V
V
Buffer Error. Data is lost. MUSYCC has no place to read or
write data internally. If from transmitter, then internal buffer
underflow. If from receiver, internal buffer overflow.
2
COFA(2)
V
V
V
V
Change of Frame Alignment. Generated when serial port is
configured in channelized mode and transmitter or receiver
synchronization signal assertion is detected during a
bit-time, and the synchronization signal is misaligned with
internal flywheel mechanism in serial interface. This
condition affects all channels in the group.
TCOFA - immediately deactivates all tx channels in the
affected group (that includes multiple groups if non-zero
PORTMAP). Therefore, after a TCOFA, MUSYCC does not
update any tx message descriptor and does not generate
any EOB/EOM interrupts unless the message is already sent
or buffer already processed. MUSYCC stops polling any
active tx channel’s descriptor and the transmit serial data
(TDAT) output should immediately go to the deactivated
state (either all ones or three-state) ascending to TRITX
setting.
RCOFA - every channel currently receiving message will
have its message terminated with COFA error. Every active
channel will be left activated.
3
ONR
V
V
V
V
V
Owner-Bit Error. Generated when next message
pointer/descriptor is not available to MUSYCC when
expected. This error is similar to BUFF error except that
MUSYCC has no place to read or write data in shared
memory, for example, when MUSYCC can not write out a
Buffer Status Descriptor.
4
PROT
V
V
V
V
V
Memory Protection Violation. Generated when memory
protection is enabled, and MUSYCC attempts a PCI master
mode access to an address outside the memory region
specified in a group’s Memory Protection Descriptor. The
memory access is inhibited.
No error to report in this interrupt.
5-7
8
5-42
Description
Reserved.
OOF(2)
V
V
V
Out of Frame. Generated when serial port is configured in
channelized mode, and receiver-out-of-frame (ROOF) input
signal assertion is detected.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
Field
Name
Value
Interrupt
Name
Channel
19:16
ERROR[3:0]
9
FCS(2)
V
V
V
V
Frame Check Sequence Error. Generated when received
HDLC frame is terminated with octet-aligned 7Eh flag, but
computed FCS does not match received FCS.
10
ALIGN(2)
V
V
V
V
Octet Alignment Error. Generated when message payload
size, after zero extraction, is not a multiple of 8 bits. This
generally occurs with an FCS error. This interrupt also
implies an FCS error. The FCS interrupt will not be
generated if the ALIGN interrupt is issued.
11
ABT(2)
V
V
V
V
Abort Termination. Generated when received message is
terminated with an abort sequence—seven sequential
1s—instead of a specific closing flag – 7Eh.
12
LNG(2)
V
V
V
V
Long Message. Generated when received message length
(after zero extraction) is greater than selected maximum
message size. Message reception is terminated and not
transferred to shared memory.
13
SHT
V
V
V
V
Short Message. Generated when received message length
(after zero extraction) is less than or equal to number of
bits in FCS field. The message data is not transferred to
shared memory.
14
SUERR
V
V
V
V
SS7 Signal Unit Error Rate Interrupt. Generated when in
SS7 mode and error monitor, SUERM, value rises past the
threshold value, SUET.
15
PERR
PCI Bus Parity Error. Generated when MUSYCC detects a
parity error on data transferred into MUSYCC either from
another PCI agent writing into MUSYCC, or from MUSYCC
reading data from shared memory. This error is specific to
the data phase of a PCI transfer while MUSYCC is receiving
data. Note: PCI system error signal, SERR*, is ignored by
MUSYCC. NOTE: To mask the PERR interrupt, MUSYCC’s
PCI Configuration Space, Function 0, Register 1, Parity
Error Response field must be set to 0.(3)
0
ILOST
No interrupts have been lost.
15
ILOST
1
100660E
Description
Rx
Tx
Bit
Field
Group
Maskable
Direction
Table 5-31. Interrupt Descriptor (3 of 4)
Interrupt Lost. Generated when internal interrupt queue is
full, and additional interrupt conditions are detected.
Because MUSYCC cannot store the newest interrupt
descriptors, it discards the new interrupts and overwrites
this bit in the last interrupt in an internal queue prior to that
interrupt being transferred out to shared memory. The
integrity of the descriptor being overwritten is maintained.
Conexant
5-43
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
BLEN[13:0]
Maskable
13:0
Direction
GRP[2]
Interrupt
Name
Description
Rx
14
Value
Tx
Field
Name
Channel
Bit
Field
Group
Table 5-31. Interrupt Descriptor (4 of 4)
MSB of Group number.
This field is relevant when EVENT field is EOB (Rx and Tx)
or EOM (Rx only). For Rx, it is equal to the number of octets
received. For Tx, it is the size of the buffer length targeted
for transmission and not necessarily the number of octets
transmitted. This field is 0 all other times.
NOTE(S):
(1)
(2)
(3)
Receive EOB and Receive EOM are concurrent events and are reported as a single interrupt; whereas Transmit EOB and EOM
are separate events and are reported as separate interrupts (two interrupt events).
Interrupt names are also reported in an error field within a receive Buffer Status Descriptor which indicates the transfer status
of a message currently being processed on a channel. The order of appearance in shared memory of a Buffer Status Descriptor
and an Interrupt Descriptor carrying the same error condition information is indeterminate. The host should confirm that both
an Interrupt Descriptor and a Buffer Status Descriptor reports the error condition.
Previously existed in bit 14 of 8474, 8472.
5.2.5.3 Interrupt Status
Descriptor
The Interrupt Status Descriptor is located in a fixed position within MUSYCC’s
internal registers. MUSYCC updates this descriptor after each transfer of
interrupt descriptors from its internal queue to the Interrupt Queue in shared
memory. The host must read this descriptor from MUSYCC registers before it
processes any interrupts. The interrupt status descriptor’s contents are reset on
hardware reset, soft chip reset, or when any field in the Interrupt Queue
Descriptor is modified.
Table 5-32 lists the details of the Interrupt Status Descriptor.
Table 5-32. Interrupt Status Descriptor
Bit
Field
Name
Value
31
RSVD
0
30:16
NEXTINT[14:0]
15
INTFULL
14:0
INTCNT[14:0]
Description
Reserved.
Next Interrupt Index. 15-bit dword index from start of Interrupt Queue up to where the
host has serviced Interrupt Descriptors.
The host can read this value to get the location of the first unserviced descriptor in
the queue. As the queue is circular, care must be taken to ensure roll-over cases at
beginning and end of queue. Only the host updates this value. The NEXTINT is a
read/write bit field. This is a 0-based number and equals the dword offset from Interrupt
Queue Pointer.
0
Interrupt Queue Not Full—shared memory.(1)
1
Interrupt Queue Full—shared memory.(1)
Interrupt Count. 15-bit value indicates the number of interrupts pushed into the
Interrupt Queue since the last reading of the Interrupt Status Descriptor. All writes to
this bit field register are ignored.
NOTE(S):
(1)
The INTFULL status is read—cleared bit field.
5-44
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
5.2.6 Interrupt Handling
5.2.6.1 Initialization
Interrupt management resources are automatically reset upon the following:
•
•
•
•
•
•
Hardware reset
Soft-chip reset service request
Global initialization service request
Read Interrupt Queue Descriptor service request
Direct memory write to Interrupt Queue Pointer
Direct memory write to Interrupt Queue Length
MUSYCC uses two interrupt queues: one is internal to MUSYCC and is
controlled exclusively by the interrupt controller logic; the other is the Interrupt
Queue in shared memory, which is allocated and administered by the host, but
written to by MUSYCC.
Upon initialization, the data in the status descriptor is reset to 0s, indicating
the first location for next descriptor, the queue is not full, and no descriptors are
in the queue. Any existing descriptors in the internal queue are discarded.
The Interrupt Status Descriptor stores the location of the next descriptor to be
read by the host, a queue full indicator, and a count of interrupts last written into
shared memory since the last read of the Interrupt Status Descriptor.
The host must allocate sufficient shared memory space for the Interrupt
Queue. Up to 32,768 dwords of queue space are accessible by MUSYCC, setting
the upper limit for the queue size. MUSYCC requires a minimum of two dwords
of queue space, setting the lower limit for the queue size.
The host must store the pointer to the queue and the queue’s length in dwords
in MUSYCC within the Interrupt Queue Descriptor register. This is done by
issuing the appropriate service request to MUSYCC. As MUSYCC takes in the
new values, it automatically resets the controller logic as indicated above. This
mechanism can also be used to switch interrupt queues while MUSYCC is in full
operation.
5.2.6.2 Interrupt
Descriptor Generation
100660E
Interrupt conditions are detected in both error and non-error cases. MUSYCC
makes a determination based on channel group, channel, and device
configuration, whether reporting the condition is to be masked or whether an
Interrupt Descriptor is to be sent to the host. If the interrupt is not masked,
MUSYCC generates a descriptor and stores it internally prior to transfer to the
Interrupt Queue in shared memory.
The internal queue is capable of holding 128 descriptors while MUSYCC
arbitrates to master the PCI bus and transfer the descriptors into the Interrupt
Queue in shared memory.
As the PCI bus is mastered and after descriptors are transferred to shared
memory, MUSYCC updates the Interrupt Status Descriptor. In making the
INTCNT field in the descriptor non-0, MUSYCC asserts the PCI INTA* signal
line.
If, during the transfer of descriptors, the Interrupt Queue in shared memory
becomes full, MUSYCC stops transferring descriptors until the host indicates
more descriptors can be written out. MUSYCC indicates it cannot transfer more
descriptors into shared memory by setting the bit field INTFULL in the Interrupt
Status Descriptor. MUSYCC has enough internal space to store 128 additional
descriptors.
Conexant
5-45
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
In cases where both shared memory queue and internal queue are full and new
descriptors are generated, those descriptors are discarded. MUSYCC indicates it
has lost interrupts internally by overwriting the bit field ILOST in the last
Interrupt Descriptor in the internal queue. The ILOST indication represents one
or more lost descriptors.
5.2.6.3 INTA* Signal
Line
The host must monitor the INTA* signal line at all times. An assertion on this line
signifies the INTCNT filed in the Interrupt Status Descriptor is non-0. A non-0
INTCNT signifies that Interrupt Descriptors have been written to the Interrupt
Queue in shared memory.
Upon detection of the INTA* assertion, the host must perform a direct read of
the Interrupt Status Descriptor from within MUSYCC. This descriptor provides
the offset to the location of the first unserviced descriptor in the queue, the
number of unserviced descriptors, and determines if the queue is full.
The INTCNT field is reset on each read of the Interrupt Status Descriptor.
As the INTCNT is reset, the INTA* signal is deasserted.
The host applies its interrupt service routines to service each of the
descriptors. As the host finishes servicing a number of descriptors, it writes the
offset to the location of the last serviced descriptor to the Interrupt Status
Descriptor, NEXTINT. A write to this field indicates to MUSYCC that descriptor
locations previously unserviced now have been serviced, and new descriptors can
be written. MUSYCC continues to write to available space whether the host
updates the NEXTINT field or not.
NOTE:
5.2.6.4 INTB* Signal
Line
5-46
After reading the Interrupt Status Descriptor, the host services all
unserviced descriptors (count of INTCNT starting at NEXTINT) in the
queue at the time of the read. If the host is unsuccessful in servicing this
set of descriptors, the host must provide an alternate method of tracking
unserviced descriptors. Every read of the status descriptors provides
information only on new descriptors placed in the queue autonomously by
MUSYCC since the last time the status descriptor was read.
A second interrupt signal line, the PCI INTB* signal line, is asserted by
MUSYCC when it detects an assertion on the EBUS EINT* signal line.
MUSYCC does not generate descriptors or use the interrupt queue for this
condition because it does not know the source or reason for the interrupt. The
reason is external to MUSYCC. This signal acts as an interrupt line pass-through
for devices connected to the EBUS. The EINT* signal line can be tied to interrupt
one or more output pins of one or more peripheral devices. As MUSYCC detects
EINT* assertion, MUSYCC asserts the INTB* towards the host as long as the
EINT* remains asserted.
Conexant
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5.0 Memory Organization
Multichannel Synchronous Communications Controller (MUSYCC™)
5.2 Descriptors
The Figure 5-2 illustrates the operation of EINT*.
Figure 5-2. Interrupt Notification To Host
MUSYCC
External Logic
Device on EBUS
Drives Interrupt Line
EINT*
Host
INTB*
Interrupt
Logic
INTA*
Interrupt
Logic
Internal Logic
Unserviced Interrupt
Descriptors in the
Interrupt Queue
Memory
Interrupt Queue
8478_022
100660E
Conexant
5-47
CN8478/CN8474A/CN8472A/CN8471A
5.0 Memory Organization
5.2 Descriptors
5-48
Multichannel Synchronous Communications Controller (MUSYCC™)
Conexant
100660E
6
6.0 Basic Operation
6.1 Reset
There are five levels of reset state:
•
•
•
•
•
Hard PCI Reset
Soft Chip Reset
Soft Group Reset
Channel Activation
Channel Deactivation
There are two ways to assert a reset:
1.
2.
Assert the PCI reset signal pin, PRST*.
Assert a service request through the host interface to perform the soft chip
reset, soft group reset, channel activation, or channel deactivation.
6.1.1 Hard PCI Reset
The PCI reset is the most thorough level of reset in MUSYCC. All subsystems
enter into their initial states. PCI reset is accomplished by asserting the PCI
signal, PRST*.
The PRST* signal is an asynchronous signal on the PCI bus. The reset signal
can be activated in several ways. The system must always assert the reset signal
on power-up. Also, a host bus to a PCI bus bridging device should provide a way
for software to assert the reset signal. Additionally, software-controlled circuitry
can be included in the system design to specifically assert the reset signal on
demand.
Asserting PRST* towards MUSYCC guarantees that data transfer operations
and PCI device operations will not begin until MUSYCC has been properly
initialized for operation. Upon entering the PCI reset state, MUSYCC outputs a
three-stated signal on all output pins and stops activity on all subsystems
including the host interface, serial interface, and expansion bus.
A PCI reset signal in MUSYCC takes one PCI clock cycle to complete, after
which the host can communicate with MUSYCC using the PCI configuration
cycles.
100660E
Conexant
6-1
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.1 Reset
6.1.2 Soft Chip Reset
A Soft Chip Reset (SCR) is a device-wide reset without the host interface’s PCI
state being reset. Serial interface operations and EBUS operations are stopped.
The soft chip reset state is entered in one of two ways:
•
•
as a result of the PCI reset
as a result of a soft chip reset service request
A SCR performs the following functions:
•
•
•
•
•
•
Sets all bits to 0 in Global Configuration Descriptor register except for
PORTMAP [1:0], which retains its current value.
Sets all bits to 0 in Interrupt Status register, including NEXTINT,
INTFULL, and INTCNT.
Sets all bits to 0 in Group Configuration Descriptor register except
MSKCOFA and MSKOOF which are set to 1. Thus, all supported groups
(both directions) are disabled.
Resets the interrupt write index to 0. Hence, the next interrupt is written at
the location pointed to by the value of Interrupt Queue Pointer. (Present
values of the Interrupt Queue Pointer and Interrupt Queue Length remain
intact.)
Deactivates all 32 channels (both directions) of each group. This action
remains pending until two serial port clocks have been applied on the
respective channel group input.
Sets all bits to 0 in the following registers:
1.
2.
3.
4.
NOTE:
Port Configuration Descriptor
Memory Protection Descriptor
Message Length Descriptor
Service Request Descriptor
SCR does not affect any PCI configuration register contents.
After the host requests a SCR by writing to the Service Request Descriptor,
MUSYCC does not acknowledge SCR execution with any Service Request
Acknowledge (SACK) Interrupt Descriptor. Although no SACK is generated,
MUSYCC will have completed execution of the transmit and receive serial port
SCR functions after two clock pulses are applied to the respective TCLK and
RCLK serial port inputs. These serial port clocks do not have to be present when
the SCR write occurs.
When writing an SCR service request, the host must ensure at least one PCI
bus clock cycle has elapsed before writing another service request. To meet this
minimum elapsed service request write timing interval, it is recommended that
the host follow any SCR write with another service request read from the same
address. Reading back the Service Request Descriptor prevents a PCI burst write
from sequentially writing different values into that descriptor.
6-2
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.1 Reset
6.1.3 Soft Group Reset
Every supported channel group within MUSYCC has the ability to reset (or
deactivate) a specific direction for all channels in the group using a single service
request: the soft group reset service request.
When a soft group reset is requested, a direction (either transmit or receive) is
specified in the request, and all channels in the specified group and direction are
deactivated. For the transmit direction, output signal TDAT is three-stated.
The host must allow two line clock periods of the clock connected to the
associated serial port to elapse for this reset to complete before issuing another
service request.
When a soft group reset is requested by the host, the service request
mechanism is used. Normally, every service request is acknowledged by
MUSYCC with a SACK Interrupt Descriptor. In this case, the host should follow
up the reset request with a Global Initialization service request.
6.1.4 Initialization Sequence Example
The typical power-up or reset initialization sequence is as follows:
1.
2.
3.
4.
5.
6.
7.
8.
9.
PCI configuration.
Soft Chip Reset.
Allocate Shared Memory.
Initialize Shared Memory Channel Group Descriptors and time slot map.
Write the Group Base Pointer values.
Allocate interrupt queue and initialize it.
Set Message Descriptor pointers.
Perform Global Initialization, waiting for SACK.
Perform Group Initialization, waiting for SACK between each service
request.
– Group Initialization - Receive Group 0–8
– Group Initialization - Transmit Group 0–8
NOTE:
100660E
SACK for Global Initialization is not written until the Global and Interrupt
Queue Descriptors are read from memory.
Conexant
6-3
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.2 Configuration
6.2 Configuration
A sequence of hierarchical initializations must occur after resets. The levels of
hierarchy are as follows:
PCI Configuration—only after hardware reset
Global Configuration
3. Interrupt Queue Configuration
4. Channel Group(s) Configuration
1.
2.
6.2.1 PCI Configuration
After power-up or a PCI reset sequence, MUSYCC enters a holding pattern,
waiting for PCI configuration cycles directed specifically for MUSYCC at the
PCI bus and PCI slot MUSYCC resides in.
PCI configuration involves PCI read and write cycles initiated by the host and
performed by a host-bus-to-PCI-bus bridge device. The cycles are executed at the
hardware signal level by the bridge device. The bridge device polls all possible
slots on the bus it controls for a PCI device and then iteratively reads the
configuration space for all supported functions on each device. All information
from the basic configuration sequence is forwarded to the system controller or
host processor controlling the bridge device.
During PCI configuration, the host can perform the following configuration
for MUSYCC’s Function 0, HDLC Network Controller function:
•
•
•
•
•
•
•
•
•
Read PCI configuration space (Device Identification, Vendor
Identification, Class Code, and Revision Identification).
Allocate 1 MB system memory range and assign the Base Address register
using this memory range.
Allow fast back-to-back transactions.
Enable PCI system error signal line, SERR*.
Allow response for PCI parity error detection.
Allow PCI bus-master mode.
Allow PCI bus-slave mode.
Assign latency.
Assign interrupt line routing.
During PCI configuration, the host can perform the following configuration
for MUSYCC’s Function 1, PCI to EBUS bridge:
•
•
•
•
•
6-4
Read PCI configuration space (Device Identification, Vendor
Identification, Class Code, and Revision Identification).
Allocate 1 MB system memory range and assign the Base Address register
using this memory range.
Allow response for PCI parity error detection.
Assign latency.
Assign interrupt line routing.
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.2 Configuration
6.2.2 Global Configuration
After PCI configuration is complete, a set of hierarchical configuration sequences
must be executed to begin operation at the channel level. Global configuration is
initiated by the host either issuing a service request or performing slave writes
into MUSYCC resident Global Configuration Descriptor.
Global configuration specifies information used across the entire device
including all supported channel groups, all channels, and the EBUS (see
Table 5-6, Global Configuration Descriptor).
NOTE:
Device identification at the PCI Level Configuration must be used to
identify the number of supported channel groups and channels in
MUSYCC, which, in turn, affects how MUSYCC is eventually configured.
6.2.3 Interrupt Queue Configuration
Part of global configuration involves interrupt queue configuration (see
Table 5-28, Interrupt Queue Descriptor).
6.2.4 Channel Group(s) Configuration
After global configuration, more specific group configuration must be performed
for each supported channel group.
The relevant references are as follows:
•
•
•
•
•
•
•
Table 5-10, Group Configuration Descriptor
Table 5-11, Memory Protection Descriptor
Table 5-12, Port Configuration Descriptor
Table 5-13, Message Length Descriptor
Table 5-14, Transmit or Receive Time Slot Map
Table 5-16, Transmit or Receive Subchannel Map
Table 5-18, Channel Configuration Descriptor
6.2.5 Service Request Mechanism
The service request mechanism requires that the host perform a direct memory
write operation (slave write) into the appropriate channel group’s Service Request
Descriptor that is within MUSYCC’s internal registers.
The relevant references are as follows:
•
•
100660E
Table 5-1, MUSYCC Register Map
Table 5-9, Service Request Descriptor
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.2 Configuration
6.2.6 MUSYCC Internal Memory
MUSYCC has two areas of host-accessible internal memories. One is the Internal
RAM (IRAM) and is accessed through MUSYCC’s Direct Memory Access
Controller (DMAC). The IRAM area contains the following descriptors and
maps:
•
•
•
Table 5-14, Transmit or Receive Time Slot Map
Table 5-16, Transmit or Receive Subchannel Map
Table 5-18, Channel Configuration Descriptor (transmit or receive)
A second area of internal memories makes up the Host Interface registers.
This area is not accessed through MUSYCC’s DMAC. The Host Interface register
contains the following descriptors:
•
•
•
•
•
•
•
•
•
•
•
•
6.2.6.1 Memory
Operations—Inactive
Channels
6.2.6.2 Memory
Operations—Active
Channels
Table 5-6, Global Configuration Descriptor
Table 5-7, Dual Address Cycle Base Pointer
Table 5-8, Group Base Pointer
Table 5-9, Service Request Descriptor
Table 5-10, Group Configuration Descriptor
Table 5-11, Memory Protection Descriptor
Table 5-12, Port Configuration Descriptor
Table 5-13, Message Length Descriptor
Table 5-14, Transmit or Receive Time Slot Map
Table 5-16, Transmit or Receive Subchannel Map
Table 5-18, Channel Configuration Descriptor
Table 5-28, Interrupt Queue Descriptor
When all channels are deactivated, the IRAM and Host Interface registers can be
read and written. The IRAM registers require that the corresponding channel
group’s line clocks (TCLK, RCLK) are active. Reading from any IRAM register
with inactive line clocks returns the pattern DEAD ACCEh—conveying "dead
access". Writing to any IRAM register with inactive line clocks returns in the
writes being ignored.
Read operations to invalid (unsupported to reserved) addresses or write-only
registers return all 1s. Write operations to invalid (unsupported or reserved)
addresses or read-only register bits result in the write to that bit location being
ignored.
There are only a few locations that are allowed to be slave-accessed after
MUSYCC has an active channel:
•
•
•
•
Group Base Pointer
Service Request Descriptor
Interrupt Status Descriptor
Any EBUS function 1 location
The host must not perform PCI slave accesses to any other register after
MUSYCC has a channel activated on any group. Any attempt to read or write to
other MUSYCC registers as a PCI slave device while channels are activated can
result in DMAC lock-up and spontaneous (unreported) channel deactivation.
This limitation is inclusive of all groups; for example, it is not acceptable to
perform a slave write to the group 2 time slot map while there is an active channel
on group 0.
6-6
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.2 Configuration
All of the slave writes can be accomplished with initial service requests after
setting the appropriate descriptor value in shared memory. Also, any value that
could be read directly from MUSYCC can more easily be read directly from the
descriptors in shared memory.
100660E
Conexant
6-7
6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
To start any channel processing, a series of shared memory segments must be
obtained by the host and initialized as specific descriptors which MUSYCC can
use to control its channel processing operations.
To illustrate the required MUSYCC configuration, assume the following:
•
•
•
•
•
Port 0 is physically wired to a PCM carrying E1 signal (2.048 Mbps).
EBUS is not used.
PCI configuration is displayed in Table 5-3, MUSYCC PCI Function
Memory Allocation.
Memory Protection is enabled for range 0x00100000 to 0x001FFFFF.
Application:
–
–
–
–
–
–
–
–
–
–
–
–
•
•
Port 0 is configured for 32 channel operation, E1 signal, 2.048 Mbps.
Transmit and Receive time slots are mapped identically.
Time slot 0 is mapped to logical channel 0 (64 kbps).
Time slot 1 bits 0–3 are mapped to logical channel 1 (32 kbps
subchannel).
Time slot 2–3 are mapped to logical channel 2 (128 kbps
hyperchannel).
16-bit FCS HDLC.
Maximum message length is 1024 octets for channel 0.
Maximum message length is 512 octets for channel 1.
Maximum message length check is disabled for channel 2.
No SS7 functions.
Idle Code = 7Eh.
Pad Fill Count = 0.
C-Language support.
Each section below builds on the previous sections.
6.3.1 Group Structure
A group structure (one per supported group) must be allocated in shared memory.
A data structure is instrumental in keeping the memory spaces for the various
descriptors required for a channel group configuration in a sequential order and at
exact offsets from the beginning of the group structure.
Once a group structure is allocated in shared memory, all descriptor spaces are
allocated within the group structure.
Service request handling within MUSYCC requires the group structure and
descriptor contents be at an exact offsets within the structure.
6-8
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
For this example, the following group structure declaration is used:
/* Reference: Chapter “Memory Organization” */
#define SIZE_OF_GROUP_STRUCTURE 1564
#define NUM_GROUPS 1
#define BOUNDARY 2048
#define MUSYCC_FUNC_0_BAR 0x00900000 /* system usually assigns this */
/* declare variable */
typedef struct tGROUP_STRUCTURE
{
unsigned long *pGroupBase;
unsigned long *pDualAddressCycleBase;
unsigned long ServiceRequestDescr;
unsigned long InterruptStatusDescr;
unsigned char Txtime slotMap[128];
unsigned char TxSubchannelMap[256];
unsigned char TxChannelConfigDescr[128];
unsigned char Rxtime slotMap[128];
unsigned char RxSubchannelMap[256];
unsigned char RxChannelConfigDescr[128];
unsigned long GlobalConfigDescr;
unsigned long InterruptDescr[2];
unsigned long GroupConfigDescr;
unsigned long MemoryProtectDescr;
unsigned long MessageLengthDescr;
unsigned long PortConfigDescr;
} tGROUP_STRUCTURE;
/*
/*
/*
/*
IMPORTANT NOTE: Byte padding within the structure would cause descriptor */
offsets from the beginning of the structure to move. MUSYCC requires every */
offset to be fixed at all times. Byte padding is an automatic function of */
many compilers. */
/* allocate space */
tGROUP_STRUCTURE GroupStr0; /* one per supported group */
/* fixed descriptor offsets into the group structure */
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
#define
100660E
GROUP_BASE_OFFSET...............0x00000000
DUAL_ADDRESS_CYCLE_BASE_OFFSET..0x00000004
SERVICE_REQUEST_OFFSET..........0x00000008
INTERRUPT_STATUS_OFFSET.........0x0000000C
TX_time slot_MAP_OFFSET..........0x00000200
TX_SUBCHANNEL_MAP_OFFSET........0x00000280
TX_CHANNEL_CONFIG_DESCR_OFFSET..0x00000380
RX_time slot_MAP_OFFSET..........0x00000400
RX_SUBCHANNEL_MAP_OFFSET........0x00000480
RX_CHANNEL_CONFIG_DESCR_OFFSET..0x00000580
GLOBAL_CONFIG_DESCR_OFFSET......0x00000600
INT_QUEUE_DESCR_OFFSET..........0x00000604
INT_QUEUE_POINTER_OFFSET........0x00000604
INT_QUEUE_LENGTH_OFFSET.........0x00000608
GROUP_CONFIG_DESCR_OFFSET.......0x0000060C
MEMORY_PROTECT_DESCR_OFFSET.....0x00000610
MESSAGE_LENGTH_DESCR_OFFSET.....0x00000614
PORT_CONFIG_DESCR_OFFSET........0x00000618
Conexant
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6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3.2 Group Base Pointer
For the Group Base Pointer the host must allocate a 2 kB bound memory segment
for Channel Group 0. The value calculated as the address for a Group Base
Structure must be written into MUSYCC’s Group 0 Base Pointer register using a
PCI write cycle. After PCI configuration, this is a simple memory access by the
host.
A service request does not exist to update this pointer in MUSYCC because
all service requests reference this pointer value to gain access to the shared
memory resident group structure and the descriptors within it.
The components of the Group Base Pointer are listed in Table 6-1.
#define SIZE_OF_GROUP_STRUCTURE 1564
#define GROUP_STR_BOUNDARY 2048
GroupStr0.pGroupBase = malloc( SIZE_OF_GROUP_STRUCTURE + GROUP_STR_BOUNDARY );
GroupStr0.pGroupBase = ( GroupStr0.pGroupBase + GROUP_STR_BOUNDARY ) &
~(GROUP_STR_BOUNDARY -1);
/*
/*
/*
/*
group base pointer pointers must be a 2K byte aligned address */
above, there is enough space to first move forward 2K bytes, then */
lop off the 2K automatically. This will bring the pointer back */
to the original address or give us the next 2K byte boundary address */
/* IMPORTANT NOTE: be sure to save away the original pointer returned by the */
/* memory access routine as that same value will be required to free the space.
*/
/* must write directly into MUSYCC register */
*(MUSYCC_FUNC_0_BAR + GROUP_BASE_OFFSET) = GroupStr0.pGroupBase;
Table 6-1. Example—Components of Group Base Pointer
6-10
Descriptor
Component of Descriptor
Value of Components
Group
Base
Pointer
Pointer to a shared memory segment large enough
for all configuration descriptors for Channel Group 0.
Return pointer from “malloc ( )” adjusted
to a 2 kB boundary.
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
6.3.3 Global Configuration Descriptor
/* CLOCK activity indicators - read only, writes are ignored */
/* MPU control - assume EBUS is not used and default values are fine */
/* PORTMAP = 0, PORT 0 mapped to CHANNEL GROUP 0 */
GroupStr0.GlobalConfigDescr = 0x00000000;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + GLOBAL_CONFIG_DESCR_OFFSET) =
GroupStr0.GlobalConfigDescr;
The components of the Global Configuration Descriptor are listed in Table 6-2.
Table 6-2. Example—Components of Global Configuration Descriptor
Descriptor
Global
Configuration
Descriptor
100660E
Component of
Descriptor
Value of Components
TXCLKACT0
TXCLKACT1
TXCLKACT2
TXCLKACT3
RXCLKACT0
RXCLKACT1
RXCLKACT2
RXCLKACT3
Read only values. Writes are ignored.
It would be ideal to read this descriptor first and verify that MUSYCC detects
clocks at the Rx and Tx ports being used.
BLAPSE
ECKEN
MPUSEL
ALAPSE
ELAPSE
0 = Don’t care.
0 = EBUS clock output disabled.
0 = Motorola-style protocol supported.
0 = Don’t care.
0 = Don’t care.
PORTMAP
Use 0 where the mapping is defined as:
Port 0 -> Channel Group 0
Port 1 -> Channel Group 1
Port 2 -> Channel Group 2
Port 3 -> Channel Group 3
Conexant
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6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3.4 Interrupt Queue Descriptor
#define
#define
#define
#define
BYTES_PER_INT_DESCR 4 /* recall, dword = 32-bits or 4 bytes */
NUM_INT_DESCR_NEEDED 10 /* assumption (min = 2, max = 32768) */
SIZE_OF_INTERRUPT_QUEUE (BYTES_PER_INT_DESCR * NUM_INT_DESCR_NEEDED)
INT_QUEUE_BOUNDARY 4
/* local variables */
unsigned long *pIntQueue;
unsigned long IntQueueLen;
pIntQueue = malloc( SIZE_OF_INTERRUPT_QUEUE + INT_QUEUE_BOUNDARY );
pIntQueue = (pIntQueue + INT_QUEUE_BOUNDARY) & ~(INT_QUEUE_BOUNDARY – 1);
/*
/*
/*
/*
interrupt queue pointers must be a dword aligned address */
above, there is enough space to first move forward 4 bytes, then */
lop off the 4 automatically. This will bring the pointer back */
to the original address or give us the next 4 byte boundary address */
/* IMPORTANT NOTE: be sure to save away the original pointer returned by the */
/* memory access routine as that same value will be required to free the space.
*/
IntQueueLen = NUM_INT_DESCR_NEEDED - 1; /* 0-based */
GroupStr0.IntQueueDescr[0] = pIntQueue;
GroupStr0.IntQueueDescr[1] = IntQueueLen;
/* either write directly into MUSYCC register - or - use a service request */
/* for this descriptor, 2 dwords need to be written, so 2 write accesses */
*(MUSYCC_FUNC_0_BAR + INT_QUEUE_POINTER_OFFSET)= GroupStr0.IntQueueDescr[0];
*(MUSYCC_FUNC_0_BAR + INT_QUEUE_LENGTH_OFFSET) = GroupStr0.IntQueueDescr[1];
The components of the Interrupt Queue Descriptor are listed in Table 6-3.
Table 6-3. Example—Components of Interrupt Queue Descriptor
Descriptor
Interrupt
Queue
Descriptor
6-12
Component of
Descriptor
Value of Components
IQPTR
pIntQueue, provided by memory allocation functions and adjusted to
be dword bound
IQLEN
IntQueueLen, specified by #define (0-based)
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
6.3.5 Group Configuration Descriptor
/* signal unit error threshold = 0, no SS7 support required */
/* sf alignment = 0, use internal flywheel mechanism after initial frame sync */
/* poll throttle = 1, poll every 16th frame */
/* inhibit tx bsd = 0, do not inhibit */
/* inhibit rx bsd = 0, do not inhibit */
/* memory protection violation action = 0, reset group on detection
/* message config bit copy = 1, enable */
/* mask cofa interrupt = 0, do not mask */
/* mask oof interrupt = 0, do not mask */
/* oof message processing = 0, continue processing incoming messages */
/* subchanneling = 0, enabled */
/* transmitter enabled = 1, enabled */
/* receiver enabled = 1, enabled */
GroupStr0.GroupConfigDescr = 0x00000443;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + GROUP_CONFIG_DESCR_OFFSET) = GroupStr0.GroupConfigDescr;
The components of the Group Configuration Descriptor are listed in Table 6-4.
Table 6-4. Example—Components of Group Configuration Descriptor
Descriptor
Group
Configuration
Descriptor
100660E
Component of
Descriptor
Value of Components
SUET
0 = SS7 not being used
SFALIGN
0 = Use internal flywheel mechanism
POLLTH
1 = Poll buffer ownership every 16th frame per channel
INHTBSD
0 = Allow tx buffer status descriptor writes
INHRBSD
0 = Allow rx buffer status descriptor writes
MEMPVA
0 = On memory protection violation, reset group
MCENBL
1 = Message configuration bits copy enabled
MSKCOFA
0 = Do not mask COFA interrupt
MSKOOF
0 = Do not mask OOF interrupt
OOFABT
0 = On OOF detection, continue processing channel
SUBDSBL
0 = Subchanneling enabled
TXENBL
1 = Transmitter enabled
RXENBL
1 = Receiver enabled
Conexant
6-13
6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3.6 Memory Protection Descriptor
/* memory protection disabled = 0 */
GroupStr0.MemoryProtectDescr = 0x00000000;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + GROUP_CONFIG_DESCR_OFFSET) =
GroupStr0.MemoryProtectDescr;
The components of the Memory Protection Descriptor are listed in Table 6-5.
Table 6-5. Example—Components of Memory Protection Descriptor
Descriptor
Component of Descriptor
Memory Protection Descriptor
PROTENBL
Value of Components
0 = Memory protection disabled
6.3.7 Port Configuration Descriptor
/* three-state transmitter output = 0 */
/* rx out of frame signal active edge = 0,
/* rx synchronization signal active edge =
/* rx data signal active edge = 0, falling
/* tx synchronization signal active edge =
/* tx data signal active edge = 0, falling
/* port mode = 1, E1 32 time slot */
GroupStr0.PortConfigDescr = 0x00000001;
falling edge */
0, falling edge */
edge */
0, falling edge */
edge */
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + PORT_CONFIG_DESCR_OFFSET) = GroupStr0.PortConfigDescr;
The components of the Port Configuration Descriptor are listed in Table 6-6.
Table 6-6. Example—Components of Port Configuration Descriptor
Descriptor
Port
Configuration
Descriptor
6-14
Component of
Descriptor
Value of Components
TRITX
0 = Three-state output when transmitter enabled and time slot is not
mapped
ROOF_EDGE
RSYNC_EDGE
RDAT_EDGE
TSYNC_EDGE
TDAT_EDGE
0 = Active edge of signals is falling edge
PORTMD
1 = 32 channel with E1 signalling
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
6.3.8 Message Length Descriptor
/* maximum frame length register 2 = 0x200 */
/* maximum frame length register 1 = 0x400 */
GroupStr0.MessageLengthDescr = 0x02000400;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + MESSAGE_LENGTH_DESCR_OFFSET) =
GroupStr0.MessageLengthDescr;
The components of the Message Length Descriptor are listed in Table 6-7.
Table 6-7. Example—Components of Message Length Descriptor
Descriptor
Message
Length
Descriptor
Component of Descriptor
Value of Components
MAXFRM2
0x200, register 2 to 512 octets
MAXFRM1
0x400, register 1 to 1024 octets
6.3.9 Transmit Time Slot Map—Channel 0
/* each time slot descriptor contains 4 time slot assignments */
/* each byte in the dword descriptor is a time slot assignment */
/* byte 0/dword 0 is for time slot 0 */
/* byte 1/dword 0 is for time slot 1 */
/* byte 2/dword 0 is for time slot 2 */
/* byte 3/dword 0 is for time slot 3 */
/* for demonstration, assign each byte separately */
GroupStr0.Txtime slotMap[0] = 0; /* zero it out for demo purposes */
/* time slot 0, channel number assigned = 0 */
/* time slot 0, time slot enabled code = 4, enabled and 64 kbps */
GroupStr0.Txtime slotMap[0] |= 0x00000080;
/* time slot 1, channel number assigned = 1 */
/* time slot 1, time slot enabled code = 7, subchannel w/ 1st bit active */
GroupStr0.Txtime slotMap[1] |= 0x0000D100;
/* time slot 2, channel number assigned = 2 */
/* time slot 2, time slot enabled code = 4, enabled and 64 kbps */
GroupStr0.Txtime slotMap[2] |= 0x00820000;
/* time slot 3, channel number assigned = 2 */
/* time slot 3, time slot enabled code = 4, enabled and 64 kbps */
GroupStr0.Txtime slotMap[3] |= 0x82000000;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + TX_time slot_MAP_OFFSET) = GroupStr0.Txtime slotMap[0];
/* the value for the first dword becomes Tx time slot Map = 0x8282D180 */
100660E
Conexant
6-15
6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
The components of the Transmit Time Slot map are listed in Table 6-8.
Table 6-8. Example—Components of Transmit Time Slot Map – Channel 0
Descriptor
Time Slot
Map
Component of Descriptor
Value of Components
TSEN3/7
4 = Time slot enabled w/ 64 kbps mode
CH3/7
2 = Logical channel 2
TSEN2/6
4 = Time slot enabled w/ 64 kbps
CH2/6
2 = Logical channel 2
TSEN1/5
7 = Time slot enables subchannel mode w/ first bit
CH1/5
1 = Logical channel 1
TSEN0/4
4 = Time slot enabled w/ 64 kbps mode
CH0/4
0 = Logical channel 0
6.3.10 Transmit Subchannel Map
/* each subchannel descriptor is made up of 2 dwords */
/* dword 0 defines the configuration of 1st 4 subchannel bits */
/* dword 1 defines the configuration of 2nd 4 subchannel bits */
/* for demonstration, assign each byte separately */
/* for this example, only logical channel 1 is being subchanneled */
/* dword 0 and 1, for logical channel 0 */
/* dword 2 and 3, for logical channel 1 */
/* dword 4 and 5, for logical channel 2 */
GroupStr0.TxSubchannelMap[4] = 0; /* zero it out for demo purposes */
GroupStr0.TxSubchannelMap[5] = 0; /* zero it out for demo purposes */
/* time slot 1, bit-0 enabled and assigned to channel 1 in time slot map */
/* time slot 1, bit-1 enabled and assigned to channel 1 in subchannel map */
GroupStr0.TxSubchannelMap[4] |= 0x00008100;
/* time slot 1, bit-2 enabled and assigned to channel 1 in subchannel map */
GroupStr0.TxSubchannelMap[4] |= 0x00810000;
/* time slot 1, bit-3 enabled and assigned to channel 1 in subchannel map */
GroupStr0.TxSubchannelMap[4] |= 0x81000000;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + TX_SUBCHANNEL_MAP_OFFSET + 4) =
GroupStr0.TxSubchannelMap[0];
*(MUSYCC_FUNC_0_BAR + TX_SUBCHANNEL_MAP_OFFSET + 5) =
GroupStr0.TxSubchannelMap[0];
/* note +4 and +5 dword offsets into the subchannel map are for channel 1 bits
*/
/* the value for the 4th dword becomes Tx Subchannel Map = 0x81818100 */
/* the value for the 5th dword becomes Tx Subchannel Map = 0x00000000 */
6-16
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
The components of the Transmit Subchannel map are listed in Table 6-9.
Table 6-9. Example—Components of Transmit Subchannel Map
Descriptor
Subchannel
Map
(dword 4)
Subchannel
Map
(dword 5)
Component of Descriptor
Value of Components
BITEN3/7
1 = Bit 3 enabled
CH3/7
1 = Logical channel 1
BITEN2/6
1 = Bit 2 enabled
CH2/6
1 = Logical channel 1
BITEN1/5
1 = Bit 1 enabled
CH1/5
1 = Logical channel 1
BITEN0/4
0 = Bit 0 not assigned here, see Time Slot Map
CH0/4
0 = Bit 0 not assigned here see Time Slot Map
TSEN3/7
0 = Bit 7 disabled
CH3/7
0 = Don’t care
TSEN2/6
0 = Bit 6 disabled
CH2/6
0 = Don’t care
TSEN1/5
0 = Bit 5 disabled
CH1/5
0 = Don’t care
TSEN0/4
0 = Bit 4 disabled
CH0/4
0 = Don’t care
6.3.11 Transmit Channel Configuration Descriptor
100660E
/*
/*
/*
/*
/*
each transmit channel descriptor is made up of 1 dwords */
need to define channel 0, 1, and 2 - 3 dwords total */
dword 0 for logical channel 0 */
dword 1 for logical channel 1 */
dword 2 for logical channel 2 */
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
for logical channel 0 */
pad count adjustment = 0, disabled */
buffer location index = 0 */
data inversion = 0, disabled */
internal buffer length = 0 */
end of padfill interrupt = 0, disabled */
protocol = 2, hdlc-16-fcs */
message length check register = 1, use register 1 */
fcs transfer = 0, normal, do not transfer rx fcs into shared memory */
mask suerr interrupt = 0, do not mask, enable interrupt */
mask sinc. interrupt = 0, do not mask, enable interrupt */
mask sdec. interrupt = 0, do not mask, enable interrupt */
mask sfilt interrupt = 0, do not mask, enable interrupt */
mask idle. interrupt = 0, do not mask, enable interrupt */
mask msg interrupt = 0, do not mask, enable interrupt */
mask eom interrupt = 0, do not mask, enable interrupt */
mask buff. interrupt = 0, do not mask, enable interrupt */
Conexant
6-17
6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
GroupStr0.TxChannelConfigDescr[0] = 0x000024000;
/* for logical channel 1 */
/* everything same except as logical channel 0 */
/* buffer location index = 1 */
/* internal buffer length = 0 */
/* message length check register = 2, use register 2 */
GroupStr0.TxChannelConfigDescr[1] = 0x01002800;
/* for logical channel 2 */
/* everything same except as logical channel 0 */
/* buffer location index = 2 */
/* internal buffer length = 0 */
/* message length check register = 0, do not check */
GroupStr0.TxChannelConfigDescr[2] = 0x02002000;
/* either write directly into MUSYCC register - or - use a service request */
*(MUSYCC_FUNC_0_BAR + TX_CHANNEL_CONFIG_DESCR_OFFSET +0) =
GroupStr0.TxChannelConfigDescr[0];
*(MUSYCC_FUNC_0_BAR + TX_CHANNEL_CONFIG_DESCR_OFFSET +1) =
GroupStr0.TxChannelConfigDescr[1];
*(MUSYCC_FUNC_0_BAR + TX_CHANNEL_CONFIG_DESCR_OFFSET +2) =
GroupStr0.TxChannelConfigDescr[2];
The components of the Channel Configuration Descriptor are listed in Table 6-10.
Table 6-10. Example—Components of Channel Configuration Descriptor
Descriptor
Transmit
Channel
Configuration
Descriptor
6-18
Component of
Descriptor
Value of Components
PADJ
0 = Pad count adjustment disabled
BUFFLOC
0 = For logical channel 0
1 = For logical channel 1
2 = For logical channel 2
INV
0 = Data inversion disabled
BUFFLEN
0 = Total FIFO = (0+1)*2 = 2 dwords
EOPI
0 = End-of-padfill interrupt disabled
PROTOCOL
2 = HDLC w/ 16-bit FC
MAXSEL
1 = For logical channel 0 application
2 = For logical channel 1 application
0 = For logical channel 2 application
FCS
0 = FCS transfer normal
MSKSUERR
MSKSINC
MSKSDEC
MSKSFILT
MSKIDLE
MSKMSG
MSKEOM
MSKBUFF
0 = Interrupt masking disabled therefore enabling these interrupts
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
6.3.12 Receive Time Slot Map
Same as Transmit Time Slot Map.
6.3.13 Receive Subchannel Map
Same as Transmit Subchannel Map.
6.3.14 Receive Channel Configuration Descriptor
Same as Transmit Channel Configuration Descriptor.
6.3.15 Message Lists
Message lists contain data transmitted or received by MUSYCC. Message lists
always reside in shared memory. Upon channel activation, MUSYCC traverses
the list and either takes data from data buffers (Tx) or puts data into data buffers
(Rx). Each direction of a channel must be assigned a message list before the
direction of that channel is activated.
A message list is a singly-linked list of Message Descriptors. A Message
Descriptor consists of a Buffer Descriptor (1 dword), a Data Pointer (1 dword),
and a Next Descriptor Pointer (1 dword). (For further information, refer to
Table 5-19, Message Descriptor).
The Buffer Descriptor contains a set of bit fields which instruct MUSYCC
how to behave after the data is put in or taken out of a data buffer.
The Data Pointer contains an address in shared memory where MUSYCC can
take data to be transmitted or store data received from the corresponding channel.
The Next Descriptor Pointer contains an address of a Message Descriptor in
shared memory where MUSYCC can access the “next” Message Descriptor in the
linked list.
To terminate a message list, the contents of the Next Descriptor Pointer in the
last descriptor in a list can point either to the address of the last descriptor or to a
general purpose “terminate” Message Descriptor that can be used by any message
list to represent the end of the list. Thus, the OWNER bit field in the last
descriptor’s Buffer Descriptor must eventually indicate that the host owns the
buffer. This bit value is opposite for receive and transmit buffer ownership.
The OWNER bit field mechanism controls the termination of the message list
as MUSYCC reads in each Message Descriptor in the linked list: it first checks
the OWNER bit field to see if it, and not the host, owns the buffer. If it does own
the descriptor, after servicing the contents of this descriptor, MUSYCC reverses
the OWNER bit field to hand the descriptor back to the host; if it does not own the
buffer, the end of the message list is automatically concluded. The channel stays
active and, depending on other bit field values in the Buffer Descriptor,
MUSYCC either polls this last descriptor regularly to see if the OWNER bit value
has changed, or it idles the channel and awaits another channel activation or
channel jump request. The former is useful in continuing a message list while
retaining the original list. The latter is useful in starting a message list from the
top element in the list.
The host processor must never change a descriptor in a buffer to which it has
already granted MUSYCC ownership. The Owner bit is the only handshake
mechanism to prevent race conditions.
100660E
Conexant
6-19
6.0 Basic Operation
CN8478/CN8474A/CN8472A/CN8471A
6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
The following describes a general sequence for setting up the transmit
Message Descriptor for a single channel:
/* assume transmit channel is currently deactivated */
/* assume that a 1024-byte message is separated into four 256-byte data buffers
*/
/* Because four buffers will be used, four 12-byte segments [or one 48-byte */
/* of shared memory is required */
/* declare structures */
typedef tDATA_BUFFER
{
unsigned char Data[256];
} DATA_BUFFER;
typedef tMSG_DESCR
{
unsigned long BufferDescr;
struct DATA_BUFFER *pDataBuffer;
struct MSG_DESCR *pNextMsgDescr;
} MSG_DESCR;
/* allocate space */
MSG_DESCR *pTxMsgDescr[4];
DATA_BUFFER *pDataBuf[4];
/* link the message descriptors together. Terminate the message list by */
/* assigning the “next” pointer in the last descriptor to point to the last */
/* descriptor itself */
pTxMsgDescr[0]->pNextMsgDescr
pTxMsgDescr[1]->pNextMsgDescr
pTxMsgDescr[2]->pNextMsgDescr
pTxMsgDescr[3]->pNextMsgDescr
=
=
=
=
pTxMsgDescr[1];
pTxMsgDescr[2];
pTxMsgDescr[3];
pTxMsgDescr[0];
/* Note: last descriptor points to itself */
/* assign each message descriptor a data buffer */
pTxMsgDescr[0]->pDataBuffer[0] = pDataBuf[0];
pTxMsgDescr[1]->pDataBuffer[1] = pDataBuf[1];
pTxMsgDescr[2]->pDataBuffer[2] = pDataBuf[2];
pTxMsgDescr[3]->pDataBuffer[3] = pDataBuf[3];
/*
/*
/*
/*
/*
/*
/*
/*
/*
/*
set the value for each buffer descriptor in each message descriptor */
OWNER bit to MUSYCC, for tx buffers set to 1, for rx set to 0 */
NP bit to enable polling, set to 0 */
EOM bit if the last data buffer is associated with this descriptor */
EOBI bit to enable end-of-buffer interrupt, set to 1 */
IC field to set the idle-code to 7Eh, set to 0 */
PADEN field to disable pad fill, set to 0 */
PADCNT field to specify 0 pad fill codes, set to 0 */
REPEAT bit to disable message retransmission, set to 0 */
BLEN field set to the length of the data buffer, set to 256 */
/* msg descr 0 */
pTxMsgDescr[0]->BufferDescr = 0x90000200;
/* msg descr 1 */
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Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
pTxMsgDescr[1]->BufferDescr = 0x90000200;
/* msg descr 2 */
pTxMsgDescr[2]->BufferDescr = 0x90000200;
/* msg descr 3 */
/* only difference is EOM bit */
pTxMsgDescr[3]->BufferDescr = 0x92000200;
/* fill data buffer with outbound traffic. each buffer contains 256-bytes of
data */
/* set the head pointer, for example for channel 0, to point to the top of */
/* the just formed message descriptor list */
/* activate transmit channel by issuing a service request */
/* ServiceRequest( ACTIVATE_CHANNEL, Group, Channel, Direction ); */
6.3.16 Channel Activation
After the previous levels of configuration are completed, individual channels
within a channel group are ready to be activated. Service requests activate
channels.
Each channel within a channel group consists of a transmitter and receiver
section. Each section is independent of the other and maintains its own state
machine, configuration registers, and internal resources. To activate both
transmitter and receiver sections, two separate service requests are required, one
directed to the transmitter and one to the receiver. MUSYCC responds to each
service request with the SACK Interrupt Descriptor, notifying the host that the
task was completed.
Channel Activation is an asynchronous command from the host interface to a
transmit or receive section of a channel to jump to a new message. Message
Descriptors in shared memory describe the attributes of the new message, what to
do between messages, and the location of message data buffers in memory to use
for transmit data or receive data.
6.3.16.1 Transmit
Channel Activation
The following describes what MUSYCC does when the transmit channel is
activated:
Reads the Tx Head Pointer for the channel from shared memory, and stores
it in the Internal Channel Descriptor map.
2. Reads the Message Descriptor pointed to by Tx Head Pointer, and stores it
in Internal Channel Descriptor map.
3. Checks bit field OWNER and NP in Buffer Descriptor.
If OWNER = 1, MUSYCC is the buffer owner. Load Channel Descriptor
map with data buffer pointer and data buffer length. Go to 4.
If OWNER = 0, MUSYCC is not the buffer owner. Can enter polling mode
until MUSYCC owns buffer or receives another service request to activate
channel or jump to new message. Repeat 3.
1.
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6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
Checks bit field INHTBSD in Group Configuration Descriptor.
If INHTBSD = 0 (i.e., MUSYCC is allowed to overwrite Buffer Descriptor
with a Buffer Status Descriptor), the address of the Buffer Descriptor is
stored in the Message Pointer slot in shared memory. After the current
message is completely processed, MUSYCC reads in the Next Message
Pointer and overwrites Buffer Descriptor. Go to 3.
If INHTBSD = 1 (i.e., MUSYCC is not allowed to overwrite Buffer
Descriptor), the address of Next Message Pointer is pre-fetched from the
current Message Descriptor and stored in the Message Pointer slot in
shared memory. After the current message is completely processed,
MUSYCC jumps to this pointer and starts processing a new message.
Go to 5 when current message is processed, otherwise repeat 4.
Simultaneously, MUSYCC masters the PCI bus and reads data into
transmit FIFO from shared memory, and the serial port outputs data using
the control lines TCLK, TSYNC, and TDAT as appropriate.
5. At end of message, Interrupt Descriptors and Buffer Status Descriptors can
be written out to shared memory (see 3)—depending on the masking of
interrupts and allowance of Buffer Descriptor overwrites.
6. Read Next Message Descriptor.
7. Go to 3.
4.
6.3.16.2 Receive
Channel Activation
The following describes what MUSYCC does when the receive channel is
activated:
Reads the Rx Head Pointer for the specified channel from shared memory,
and stores in the Internal Channel Descriptor map.
2. Reads the Message Descriptor pointed to by Head Pointer, and stores in the
Channel Descriptor map.
3. Check bit field OWNER and NP in Buffer Descriptor.
If OWNER = 0, MUSYCC is the buffer owner. Load Channel Descriptor
map with data buffer pointer and data buffer length. Go to 4.
If OWNER = 1, MUSYCC is not the buffer owner. May enter polling
mode until MUSYCC owns buffer or receives another service request to
activate channel. Repeat 3.
4. Check bit field INHRBSD in Group Configuration Descriptor.
If INHRBSD = 0 (i.e., MUSYCC is allowed to overwrite Buffer Descriptor
with a Buffer Status Descriptor), the address of the Buffer Descriptor is
stored in the Message Pointer slot in shared memory. After current
message is completely processed, MUSYCC reads in Next Message
Pointer and overwrites Buffer Descriptor. Go to 3.
If INHRBSD = 1 (i.e., MUSYCC is not allowed to overwrite Buffer
Descriptor), the address of Next Message Pointer is pre-fetched from the
current Message Descriptor and stored in the Message Pointer slot in
shared memory. After the current message is completely processed,
MUSYCC jumps to this pointer and starts processing the new message.
Go to 5 when current message is processed, otherwise repeat 4.
Simultaneously, the receiver is configured and data is sampled in from the
serial port using control lines RCLK, RSYNC, RDAT, and ROOF as
appropriate, and, MUSYCC masters the PCI bus and transfers data from
the internal FIFO to shared memory.
1.
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6.3 Channel Operation
At end of message, Interrupt Descriptors and Buffer Status Descriptors can
be written out to shared memory (see 3)—depending on the masking of
interrupts and allowance of Buffer Descriptor overwrites.
6. Read Next Message Descriptor.
7. Go to 3.
5.
NOTE:
MUSYCC responds to either a JUMP or ACTIVATE service request by
reading first the head pointer and then the Message Descriptor pointed to
by the Head Pointer. Therefore, software must set up the new head pointer
and Message Descriptors (i.e., buffer list) before issuing either a JUMP or
ACTIVATE service request.
6.3.17 Channel Deactivation
After the channel has been activated, channel deactivation via a service request
suspends activity on an individual channel-direction by stopping that channel’s
processing of the current buffer list. The only indication that MUSYCC has
completely stopped its list processing is a SACK interrupt. Therefore, the host
must wait for a SACK before setting up the new buffer list.
Each channel within a channel group consists of a transmitter and receiver
section. Each section is independent of the other and maintains its own state
machine and configuration registers. To deactivate both transmitter and receiver
sections, two separate service requests are required—one directed to the
transmitter and one to the receiver. MUSYCC responds to each service request
with the SACK Interrupt Descriptor, which notifies the host that the task was
completed.
A channel deactivation is an asynchronous command from the host interface
to a transmit or receive section of a channel to suspend bit-level processing and
halt memory transfers into shared memory.
6.3.17.1 Transmit
Channel Deactivation
The following describes what MUSYCC does when the transmit channel is
deactivated:
Current message processing is terminated destructively; that is, data can be
lost and messages prematurely aborted.
2. The bit-level processor responsible for handling outbound bits to the serial
port is immediately and asynchronously disabled. The data output pin,
TDAT, is three-stated or held at logic 1, depending on the bit field TRITX
in the Port Configuration Descriptor. Data transfers from shared memory
are halted.
3. The channel direction remains in the suspended state until the channel is
activated. The current channel direction configuration is maintained.
1.
6.3.17.2 Receive
Channel Deactivation
The following describes what MUSYCC does when the receive channel is
deactivated:
Current message processing is terminated destructively; that is, data can be
lost and messages prematurely aborted.
2. The bit-level processor responsible for handling inbound bits from the
serial port is immediately and asynchronously disabled. Data transfers to
shared memory are halted.
3. The channel direction remains in the suspended state until the channel is
activated. The current channel direction configuration is maintained.
1.
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Multichannel Synchronous Communications Controller (MUSYCC™)
6.3.18 Channel Jump
A channel jump request is issued by the host via a service request. For a receiver,
channel jumps are the same as channel activation.
For a transmitter, channel jumps are non-destructive to currently serviced
messages. The channel state is not reset as in the channel activate sequence.
Therefore, a transmitter channel must be activated first, then subsequent jump
requests can be made using the channel jump service request. For a transmitter,
channel jumps provide a non-destructive way to start transmitting a new message
list. MUSYCC waits until the completion of the current message before jumping
to a message list pointed to by a new Head Pointer.
A jump request is issued by the host via a service request towards a channel in
a channel group in MUSYCC.
NOTE:
The service request acknowledge (via the SACK Interrupt Descriptor) for
the jump service request—specifically for the transmit direction—will not
be output towards the host until after the current message is transmitted.
For applications with long messages to transmit, the jump service request
must be used with care.
6.3.19 Frame Alignment
Each serial port frame consists of a fixed number of bits grouped into time
slots according to the frame alignment supplied by the serial port TSYNC and
RSYNC signals. MUSYCC must be provided at least one external
synchronization pulse on the TSYNC and RSYNC input pins after the respective
channel group is enabled. After this initial sync pulse, MUSYCC tracks
subsequent serial port frame boundaries using its internal flywheel mechanism or
the next applied sync pulse.
NOTE:
Nx64 serial port mode does not operate the internal flywheel and therefore
requires periodic TSYNC and RSYNC pulses to keep track of serial port
frame boundaries.
In addition to tracking serial port frame boundaries, the internal flywheel
generates a frame synchronization signal that can be selected to control the
channel group's alignment of Transparent mode channel data streams. By default,
the frame synchronization signal from the internal flywheel determines
Transparent mode channel data stream alignment. If external data stream
synchronization is preferred, the SFALIGN bit field in the Group Configuration
Descriptor can be set to expect this synchronization signal to come from the serial
port TSYNC and RSYNC input pins. While SFALIGN is set, the internal
flywheel continues to operate, but the synchronization signal from the flywheel is
not used to determine data stream alignment. Instead, alignment is provided by
the external framer device which is allowed to strobe the sync input pins at
periodic frame intervals or at any desired multiple of the frame interval
(i.e., superframe).
Each serial port frame carries stream data from one or more packetized HDLC
or unpacketized Transparent mode channels. Although channels are mapped to
specific time slots within the serial port frame, each channel's data streaming
process may or may not have a particular alignment with respect to that channel's
assigned time slot boundaries, depending upon whether the channel is configured
to operate in HDLC or Transparent mode.
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Multichannel Synchronous Communications Controller (MUSYCC™)
6.3 Channel Operation
For HDLC mode channels, data stream processing begins immediately upon
channel activation. Any type of alignment of a HDLC channel's data stream with
respect to its assigned serial port time slots is unnecessary, and MUSYCC
disables time slot synchronization for that channel. Therefore, no specific
alignment exists or needs to exist between the first bit of a HDLC message and
the first bit of the assigned channel time slot.
After activation of a Transparent mode channel, the SFALIGN setting selects
whether that channel's bit-level processor either waits for a frame synchronization
signal from the internal flywheel, or an external synchronization signal from the
serial port sync input pin before starting the data stream process. The selected
synchronization signal (internal or external) thus determines the alignment of that
channel's data stream with respect to its assigned serial port time slot. This time
slot alignment mechanism ensures Transparent mode channel's are able to
transfer sampled voice data streams to and from bytes stored in Shared Memory
while maintaining the alignment of those bytes with respect to the serial port time
slot. In Transparent mode MUSYCC is required to point to a MUSYCC-owned
buffer prior to a channel activation service request.
For Transparent mode hyperchannels, where multiple time slots are mapped to
a single channel, the first byte of data to and from the Shared Memory buffer is
aligned to the lowest numbered serial port time slot mapped to that hyperchannel.
If the lowest numbered time slot mapped to that hyperchannel equals time slot 12,
the bit-level processor aligns the first byte of Shared Memory buffer data to time
slot 12 and the next byte of data to the next higher numbered time slot that is also
mapped to that hyperchannel. This sequence of time slot mapped alignment is
true for all Transparent mode hyperchannel cases except when time slot 0 is the
lowest numbered time slot mapped. In which case, the first byte of Shared
Memory buffer data is transferred to the next higher numbered time slot. For
example, a Transparent mode hyperchannel mapped to time slot 0, and time slot 1
would output the first byte of Shared Memory data during time slot 1 and would
write receive data from time slot 1 into the first byte of the Shared Memory
buffer.
6.3.20 Descriptor Polling
Upon channel activation and any necessary frame alignment, MUSYCC must
fetch Message Descriptors from shared memory to start the flow of message bits
into and out of shared memory.
As a Buffer Descriptor is fetched, MUSYCC checks the owner-bit to verify if
the buffer is serviceable by MUSYCC. If the owner bit indicates that the host still
owns the buffer, the host has not yet prepared the data in the buffer for processing.
This may or may not be an error condition. In this case, MUSYCC also must
check the no-poll bit in the same descriptors to determine if polling for MUSYCC
ownership is enabled.
If the host owns the buffer and polling is disabled, the channel direction is
suspended from processing messages until the host intervenes with a subsequent
channel activation or channel jump request. The channel is not capable of leaving
this suspended state autonomously.
If the host owns the buffer and polling is enabled, the channel direction is
suspended from processing messages and MUSYCC periodically polls the owner
bit in the Buffer Descriptor to verify that the buffer is ready for MUSYCC. The
channel is capable of leaving this suspended state autonomously.
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6.3 Channel Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
The frequency of polling is controlled independently for each channel group
by the SFALIGN (superframe alignment) and POLLTH (poll throttle) bit fields in
the Group Configuration Descriptor.
The SFALIGN bit field defines the source of the synchronization event to be
used by MUSYCC. The source is either an internal flywheel method or an
external signal at the serial port.
NOTE:
Time slot counter or flywheel time base method uses a 7-bit counter. As
each bit is serviced, over 32 channels with 8 bits per channel in a
2.048 MHz data stream, the counter is incremented. When the counter
rolls over to 0, a Beginning of Frame is declared. At 2.048 MHz, 256 bits
represents 125 ms.
The POLLTH bit field specifies how often MUSYCC checks the owner bit in
a host-owned Buffer Descriptor. The values correspond to 1-, 16-, 32-, or
64-frame periods, or 125 µs, 2 ms, 4 ms, and 8 ms, respectively. The POLLTH bit
field is always used in conjunction with the SFALIGN bit field. Table 6-11 lists
the various polling frequencies and times.
If the serial port is configured for Nx64 mode (a variable number of 64 kbps
channels assigned to form one logical channel), the Time Slot Counter is reset
only when the inputs TSYNC or RSYNC are asserted. In this case, the SFALIGN
bit field is always ignored.
Table 6-11. Polling Frequency Using a Time Slot Counter Method
Standard Channelized Input
Poll Throttle Value (Multiples of Frames)
Name
Rate (MHz)
Bits Per Frame
0 (x1)
1 (x16)
2 (x32)
3 (x64)
T1
1.536
192
125 µs
2 ms
4 ms
8 ms
E1
2.048
256
125 µs
2 ms
4 ms
8 ms
2 E1
4.096
512
125 µs
2 ms
4 ms
8 ms
4 E1
8.192
1024
125 µs
2 ms
4 ms
8 ms
6.3.21 Repeat Message Transmission
MUSYCC provides a mechanism to repeatedly transmit a single message. A
transmitter channel enters the repeat mode if the REPEAT bit field is 1, and the
EOM bit field is 1 in a Transmit Buffer Descriptor.
NOTE:
The message being repeatedly transmitted be specified completely by a
single Message Descriptor and not by a linked list of descriptors.
A repeating message either fits entirely in the internal FIFO buffer space
allocated for the transmitter channel, or the message is accessed in pieces over the
PCI bus and then re-accessed from the beginning when the end of buffer is
reached. The determination of whether the message fits entirely in the FIFO
buffer or not is automatically performed each time MUSYCC enters repeat mode.
MUSYCC compares the BLEN bit field (which specifies the number of bytes in
the message) from the Transmit Buffer Descriptor to [(BUFFLEN + 1) x 2]
(which specifies the number of dwords in the FIFO buffer) from the Channel
Configuration Descriptor.
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6.3 Channel Operation
To exit repeat mode after the current message is completely transmitted and
before the next repetition (gracefully or non-destructively), a channel jump
service request must be issued. Prior to the jump request, the host must initialize
the channel’s Transmit Head Pointer with a new Message Descriptor.
To exit repeat mode, regardless of the message being processed, a channel
activate or a channel deactivate service request can be issued. Either is considered
destructive because the current message transmission is aborted.
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Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
6.4 Protocol Support
6.4.1 Frame Check Sequence
MUSYCC is configurable to calculate either a 16- or 32-bit Frame Check
Sequence (FCS) for HDLC packets ranging in size from a minimum of 2 octets to
a maximum of 16,384 octets. The FCS always applies to the entire packet length.
For all HDLC modes which require FCS calculations, the polynomials used to
calculate the FCS are according to ITU-T Q.921 and ISO 3309-1984.
•
CRC-16:
x
•
16
+x
12
5
+x +1
CRC-32:
x
32
+x
26
+x
23
+x
22
+x
16
+x
12
+x
11
+x
10
8
7
5
4
2
+x +x +x +x +x +x+1
6.4.2 Opening/Closing Flags
For HDLC modes only, MUSYCC supports the use of opening and closing
message flags. The 7Eh (01111110b) flag is the opening and closing flag. An
HDLC message is always bounded by this flag at the beginning and the end of the
message.
MUSYCC supports receiving a shared flag where the closing flag of one
message can act as the opening of the next message. MUSYCC also supports
receiving a shared 0 bit between two flags, i.e., the last 0 bit of one flag is used as
the first 0 bit of the next flag.
MUSYCC can be configured to transmit a shared flag between successive
messages by configuring the bit field PADEN in each Transmit Buffer Descriptor.
MUSYCC does not transmit shared 0 bits between successive flags.
6.4.3 Abort Codes
Seven consecutive 1s constitute an abort flag. Receiving the abort code causes the
current frame processing to be aborted and terminates further data transfer into
shared memory. After detecting the abort code, MUSYCC enters a mode
searching for a new opening flag.
Notification of this detected condition is provided by the receive Buffer Status
Descriptor or an Interrupt Descriptor, indicating the error condition Abort Flag
Termination.
In cases where received idle codes transition to an abort code, an Interrupt
Descriptor is generated toward the host indicating the informational event Change
to Abort Code. All received abort codes are discarded.
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6.4 Protocol Support
6.4.4 Zero-Bit Insertion/Deletion
MUSYCC provides 0-bit insertion and deletion when it encounters five
consecutive 1s within a frame. In the receiver, a 0 bit is de-inserted, and in the
transmitter a 0 bit is inserted after five 1s are seen.
6.4.5 Message Configuration Bits
A group of bits specified in a Transmit Buffer Descriptor specifies the data to be
transmitted at the transmit channel after the end of a current message has been
transmitted. The bits are collectively known as the Message Configuration
Descriptor and include the specifications for the following:
•
•
•
•
6.4.5.1 Idle Code
Idle Code specification, IC
Inter-message Pad Fill Enable, PADEN
Inter-message Pad Fill Count, PADCNT
Repeat Message Transmission, REPEAT
The Idle Code (IC) specification allows an idle code to be transmitted after the
current message in case the next message is not available to be transmitted or
inter-message pad fill is requested via PADEN.
6.4.5.2 Inter-message
Pad Fill
The Pad Enable (PADEN) and Pad Count (PADCNT) specifications allow pad fill
octets (a sequence of one or more specified idle codes) to be transmitted between
messages. PADEN enables or disables the pad fill octet transmission feature.
PADCNT is the minimum number of fill octets to be transmitted between the
closing flag of one message and the opening flag of the next message.
6.4.5.3 Repeat Message
Transmission
The Repeat Message Transmission (REPEAT) specification allows a single
message to be transmitted repeatedly without additional host intervention. This
feature is required to support SS7 message retransmission. In the SS7 application,
a retransmitted message is usually 3, 4, or 5 octets in length. Message
retransmission in MUSYCC requires that the entire message be held in a single
shared memory message buffer, versus being spread across multiple buffers. The
message retransmission feature is not limited to SS7 applications.
6.4.6 Message Configuration Bits Copy Enable/Disable
The message configuration bits described above are used in special data
communication applications requiring the following attributes specified on a
per-message basis:
•
•
•
Specific idle code is to be transmitted between messages.
Inter-message pad fill is required.
Repeat message transmission is required.
If at least one transmit channel in a channel group is supporting an application
which requires any one of the above attributes, the Message Configuration Bits
Copy must be enabled for the entire channel group by setting the MCENBL
bit field to 1.
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6.4 Protocol Support
Setting MCENBL to 0 prevents MUSYCC from copying the Message
Configuration Bits from the Transmit Buffer Descriptor and has the following
effect on transmit channel operations throughout the channel group:
•
•
PADEN and PADCNT are set to 0, thereby facilitating back-to-back
message transmission.
REPEAT is set to 0, thereby disabling automatic message retransmission.
Any of the Message Configuration Bits can be changed by writing new values
for these bit fields directly into a channel group’s Transmit Configuration Table.
However, the exact time the new bit field values are applied by the transmitter is
unrelated to the message being serviced. If the channel is idle, any change to the
message configuration bits in the Configuration Table will apply to subsequent
messages.
To write new configuration bits into the Transmit Message Configuration
Table, a PCI dword operation is required. Tables 6-12 and 6-13 list the address
map and the Message Configuration Descriptor layouts.
Table 6-12. Memory Map for Message Configuration Descriptor Table
Channel
Number
(0–31)
Location of Message Configuration Descriptor
in Specific Group (0–3) (Byte offset from Base Address Register)
0
1
2
3
4
5
6
7
0
06180h
06980h
07180h
07980h
16180h
16980h
17180h
17980h
1
06184h
06984h
07184h
07984h
16184h
16984h
17184h
17984h
x
Address of Message Configuration Descriptor for a
channel in a group
06180h + (Group_Number[0:3]•00800h) +
(Channel_Number[31:0]•00008h)
Address of Message Configuration Descriptor for a
channel in a group
16180h + (Group_Number[4:7]•00800h) +
(Channel_Number[31:0]•00008h)
31
061FCh
161FCh
069FCh
071FCh
079FCh
169FCh
171FCh
179FCh
Table 6-13. Message Configuration Descriptor (1 of 2)
6-30
Bit
Field
Name
Value
31:27
RSVD
0
Reserved.
26:25
IC
0
Idle Code Select –7Eh (0111 1110b)
1
Idle Code Select –FFh (1111 1111b)
2
Idle Code Select –00h (0000 0000b)
3
Idle Code Select –Reserved.
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6.4 Protocol Support
Table 6-13. Message Configuration Descriptor (2 of 2)
Bit
Field
Name
Value
24
PADEN
0
Pad Fill Disabled. One shared opening/closing flag
(7Eh) is inserted before sending next message
1
Pad Fill Enabled. Also, see PADCNT bit field.
Description
23:16
PADCNT[7:0]
0
Pad Count. When PADEN = 1, PADCNT indicates the
minimum number of idle codes to be inserted
between the closing flags and the next opening flag
(7Eh).
If PADCNT = 2 and IC = 1, for example, yields the
bit pattern 7Eh..FFh..FFh..7Eh
There is no indication by MUSYCC if more than
PADCNT number of idle codes are inserted.
15
REPEAT
0
Repeat Message Transmission Disabled.
1
Repeat Message Transmission Enabled.
0
Reserved.
14:0
RSVD
6.4.7 Bit-Level Operation
Each channel group provides two separate Bit-Level Processors (BLP) to service
the transmit and receive directions separately. Also, each channel group provides
two separate Direct Memory Access Controllers (DMAC) to service the transmit
and receive directions separately. The BLP and DMAC work in conjunction to
transfer serial data between the serial interface and shared memory. BLPs
perform the required bit-level processing based on the protocol mode assigned to
the channel and direction.
DMACs access the data to transmit or store the received data to shared
memory (via the host interface). Each DMAC seeks out the next Message
Descriptor to service for each active channel and direction. This information is
available from the Channel Group Descriptor in shared memory which has
information locating the message list for each channel direction. A Buffer
Descriptor within each Message Descriptor along with the protocol mode set for
the channel-direction drives the treatment of the receive and transmit bit stream.
Bit-level operations vary between HDLC and transparent modes. The
differences relate to protocol-specific support, as well as to the treatment of the
bit stream during abnormal conditions. Additionally, bit-level operations are
independent and sometimes differ between the transmitter and the receiver.
100660E
Conexant
6-31
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
The following items apply to all event and error handling as described in the
transmit and receive sections which follow:
•
•
•
•
6.4.7.1 Transmit
During bit level operations, events and errors can affect the outcome
message processing. Unless masked, all events and errors generate
Interrupt Descriptors within MUSYCC. Interrupt Descriptors identify the
error or event condition, the transmit or receive direction, and the channel
and channel group number affected.
If a channel is suspended, enters an idle mode, enters an abort mode, or is
autonomously turned off by MUSYCC during bit-level operations, a
channel reactivation must occur by either a Channel Activation Service
Request or a Channel Jump Service Request. This is referred to as
“requiring reactivation.”
The bit fields INHTBSD and INHRBSD in the Group Configuration
Descriptor specify whether or not MUSYCC can write a Buffer Status
Descriptor into a Message Descriptor to indicate that MUSYCC has
completed servicing the descriptor.
In cases where bit-level operations continue normally, the DMAC accesses
the Next Message Pointer from the current Message Descriptor. This
accesses the next Message Descriptor in the chain of descriptors for a
particular channel and direction. Each Message Descriptor indicates
whether or not the host or MUSYCC owns the descriptor.
The transmitter initiates data transfer from shared memory to the serial interface
only if the following conditions are true:
•
•
•
TXENBL bit is set to 1 in the Group Configuration Descriptor.
Transmit channel is mapped to logical channel(s) in Transmit Time Slot
Map.
Transmit channel is (re)activated (via service request).
If the TXENBL bit is set to 0, the output signal is a three-state signal. If the
channel is not mapped or is inactive, the transmitter either outputs a three-state or
an all 1s signal depending on the state of the bit field TRITX in the Group
Configuration Descriptor.
6.4.7.2 Receive
The receiver transfers data from the serial interface to memory buffers in shared
memory only if all the following conditions are true:
•
•
•
RXENBL bit is set to 1 in the Group Configuration Descriptor.
Receive channel is mapped to one or more logical channel(s) in Receive
Time Slot Map.
Receive channel is (re)activated (via service request).
If any one of the above conditions is not true, the receiver ignores the
incoming data stream.
Data transfer consists of MUSYCC first seeking out the next Message
Descriptor from the Channel Group Descriptor in shared memory for each active
channel. The Buffer Descriptor in each Message Descriptor plus the protocol
mode set for the channel dictates the treatment of the incoming bit stream.
6-32
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
6.4.8 HDLC Mode
MUSYCC supports three HDLC modes. The modes are assigned on a
per-channel and direction basis by setting the PROTOCOL bit field within the
Channel Configuration Descriptor. The HDLC modes are as follows:
•
•
•
SS7-HDLC-16CRC: specific SS7 support, HDLC support, 16-bit CRC.
HDLC-16CRC: HDLC support, 16-bit CRC.
HDLC-32CRC: HDLC support, 32-bit CRC.
HDLC support by the transmitter includes the following:
•
•
•
•
•
Generating opening, closing, and shared flags.
0-bit insertion after five consecutive 1s are transmitted.
Generating pad fill between frames and adjust for 0 insertions.
Generating 16- or 32-bit FCS.
Generating abort sequences upon data corruption in message.
HDLC support by the receiver includes the following:
•
•
•
•
•
•
•
•
Detection and extraction of opening, closing, and shared flags.
Detection of shared 0 between successive flags.
0-bit extraction after five consecutive 1s are received.
Detecting changes in pad fill idle codes.
Checking and extracting 16- or 32-bit FCS.
Checking frame length.
Checking for octet alignment.
Checking for abort sequence reception.
Bit Fields within the Transmit Buffer Descriptor specify inter-message bit
level operations. Specifically, when the EOM bit field is set to 1 within a Message
Descriptor by the host, it signifies that the descriptor represents the last buffer for
the current message being transmitted and the bit fields IC, PADEN, PADCNT,
and REPEAT take effect. These bits are collectively known as Message
Configuration Descriptor.
Additionally, the bit field NP in both the Receive and Transmit Buffer
Descriptors enables a polling scheme in case MUSYCC discovers that it does not
own the (next) Message Descriptor.
6.4.8.1 Transmit Events
End of Buffer (EOB]
Transmit events are informational in nature and do not require channel recovery
actions.
Reason:
•
DMAC reached the end of a buffer by servicing a number of octets equal
to the bit field BLEN in the Transmit Buffer Descriptor. The last EOB and
an EOM are coincident and result in two separate events being generated.
Effects:
•
•
100660E
Interrupt Descriptor in Interrupt Queue with EVENT = EOB, DIR = 1
(if EOBI = 1 in Transmit Buffer Descriptor).
BLP and DMAC continue with normal message processing. If the DMAC
does not receive more data from shared memory before the BLP must
output the next data bit, the BLP outputs another octet of idle code.
Conexant
6-33
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
End of Message (EOM]
Reason:
•
BLP has transmitted the last bit of a data buffer and the Transmit Buffer
Descriptor signified the end of a message by the bit field EOM in a
Transmit Buffer Descriptor. The last EOB and an EOM are coincident and
result in two separate events being generated.
Effects:
•
End of Padfill (EOP]
Interrupt Descriptor in Interrupt Queue with EVENT = EOM, DIR = 1
(if MSKEOM = 0 in Transmit Channel Configuration Descriptor).
• BLP and DMAC continue with normal message processing. If the DMAC
does not receive more data from shared memory before the BLP must
output the next data bit, the BLP outputs another octet of idle code.
Reason:
• BLP has transmitted the specified number of pad fill octets.
Effects:
•
•
6.4.8.2 Receive Events
End of Buffer (EOB)
Interrupt Descriptor in Interrupt Queue with EVENT = EOP, DIR = 1
(if EOPI = 1 in Transmit Channel Configuration Descriptor).
BLP and DMAC continue with normal message processing. If the DMAC
does not receive more data from shared memory before the BLP must
output the next data bit, the BLP outputs another octet of idle code.
Receive events are informational in nature and do not require channel recovery
actions.
Reason:
•
One message is stored across multiple message buffers. MUSYCC reached
the end of a buffer by servicing a number of octets equal to the bit field
BLEN in a Receive Buffer Descriptor.
Effects:
•
•
End of Message (EOM)
The Interrupt Descriptor in the Interrupt Queue with EVENT = EOB,
DIR = 0
(if EOBI = 1 in Receive Buffer Descriptor).
BLP and DMAC continue with normal message processing.
Reason:
•
BLP detected the end of a message (closing flag or an error condition) in
the received data stream. Error conditions include ABT, LNG, ALIGN,
BUFF, and ONR errors.
Effects:
•
•
•
6-34
Interrupt Descriptor in Interrupt Queue with EVENT = EOM, DIR = 0
(if MSKEOM = 0 in Receive Channel Configuration Descriptor).
DMAC sets bit field EOM = 1 in Receive Buffer Status Descriptor
(if INHRBSD = 0 in Receive Channel Configuration Descriptor).
BLP and DMAC continue with normal message processing.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
Change to Abort
Code (CHABT)
6.4 Protocol Support
Reason:
•
BLP detected received data changed from pad fill (7Eh) octets to abort
code (zero followed by seven consecutive 1s).
Effects:
•
•
Change to Idle Code (CHIC)
Interrupt Descriptor in Interrupt Queue with EVENT = CHABT, DIR = 0
(if MSKIDLE = 0 in Receive Channel Configuration Descriptor).
BLP and DMAC continue with normal message processing.
Reason:
•
BLP detected received data changed from abort code (0 followed by
seven 1s) to idle code (7Eh) octets.
Effects:
•
•
Frame Recovery (FREC)
Interrupt Descriptor in Interrupt Queue with EVENT = CHIC, DIR = 0
(if MSKIDLE = 0 in Receive Channel Configuration Descriptor).
BLP and DMAC continue with normal message processing.
Reason:
•
BLP detected that the serial interface has transitioned from an
out-of-frame to in-frame condition.
Effects:
•
SS7 SUERM Octet Count
Increment (SINC)
Interrupt Descriptor in Interrupt Queue with EVENT = FREC, DIR = 0
(if MSKOOF = 0 in Group Configuration Descriptor).
• BLP and DMAC continue with normal message processing.
Reasons:
•
BLP incremented the SUERM counter. The channel is in SS7 mode. The
reasons for SUERM counter to increment include reception of a short
message, octet alignment error, FCS mismatch, or an accumulation of
octet count errors. Each of these conditions may also generate an interrupt.
Effects:
•
SS7 SUERM Octet Count
Decrement (SDEC)
Interrupt Descriptor in Interrupt Queue with EVENT = SINC, DIR = 0
(if MSKSINC = 0 in Receive Channel Configuration Descriptor).
• BLP and DMAC continue with normal message processing.
Reasons:
•
BLP decremented the SUERM counter. The channel is in SS7 mode. The
SUERM counter decrements by one when MUSYCC receives 256
consecutive unerrored messages.
Effects:
•
SS7 Filtered Message
(SFILT)
100660E
Interrupt Descriptor in Interrupt Queue with EVENT = SDEC, DIR = 0
(if MSKSDEC = 0 in Receive Channel Configuration Descriptor).
• BLP and DMAC continue with normal message processing.
Reason:
•
BLP detected an unerrored 3, 4, or 5 octet message identical to the
previous message. The channel is in SS7 mode.
Conexant
6-35
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
Effects:
•
•
•
6.4.8.3 Transmit Errors
Underflow Due to Host
Ownership of Buffer (ONR)
Interrupt Descriptor in Interrupt Queue with EVENT = SFILT, DIR = 0
(if MSKSFILT = 0 in Receive Channel Configuration Descriptor).
BLP discards the received message in the FIFO.
BLP and DMAC continue with normal message processing.
Transmit errors are service-affecting and require a corrective action by a
controlling device to resume normal bit-level processing.
In this case, MUSYCC attempts to access the [next] Message Descriptor when the
prior descriptor contained only a portion of the message (EOM = 0), and
MUSYCC finds that ownership of the [next] descriptor has not been granted by
the host (i.e., the next buffer is host-owned).
This error results when currently transmitting an HDLC message, and no
additional descriptors are available in a timely manner.
Once a descriptor is granted, however, MUSYCC assumes ownership of the
message buffer and continues reading data until the end of buffer is reached. If the
host reclaims the buffer without MUSYCC granting ownership back to the host, a
host error occurs, and the effects are indeterminate.
Reason:
•
Degradation of the host subsystem or application software performance.
Effects:
•
•
•
•
•
•
Partial HDLC message transmission has occurred.
Interrupt Descriptor in Interrupt Queue with ERROR = ONR, DIR = 1
(if MSKBUFF = 0 in Transmit Channel Configuration Descriptor).
Transmit channel enters abort state where the BLP transmits a repetitive
abort sequence of 16 consecutive 1s.
Transmit Buffer Status Descriptor cannot be written.
Message polling is automatically disabled.
Transmit channel enters abort state.
Channel Level Recovery Actions:
Underflow Due to Internal
FIFO Buffer Under-Run
(BUFF)
• Transmit channel reactivation is required.
In the case of underflow due to internal FIFO buffer under-run, the internal FIFO
buffer becomes empty when MUSYCC transmits data bits (at the serial interface
clock rate), and MUSYCC has ownership of a message buffer in shared memory.
Reasons:
•
•
Degradation of the host subsystem or application software performance.
Congestion of the PCI bus.
Effects:
•
•
•
•
Interrupt Descriptor in Interrupt Queue with ERROR = BUFF, DIR = 1
(if MSKBUFF = 0 in Transmit Channel Configuration Descriptor).
Transmit channel enters abort state where the BLP transmits a repetitive
abort sequence of 16 consecutive 1s.
Message polling is automatically disabled.
Transmit Buffer Status Descriptor is not written.
Channel Level Recovery Actions:
•
6-36
Transmit channel reactivation is required.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
Change of Frame Alignment
(COFA) while Transmitting
HDLC Message
(T1/E1 modes)
6.4 Protocol Support
In the case of change of frame alignment while transmitting an HDLC message
(T1/E1 modes), the TSYNC input signal transitions from low to high when not
expected to do so by the frame synchronization flywheel mechanism. This error
only applies to ports configured for T1, E1, 2xE1 or 4xE1 signals. Frame
synchronization indicates the location of time slot 0 in the serial data stream.
Lacking frame synchronization, the transmitter cannot map and align time slots.
This error affects all active channels in the channel group.
Reason:
•
T1/E1 signal failure is detected by the physical interface providing the
serial data, clock frequency, and synchronization to the serial interface on
MUSYCC.
Effects:
•
•
•
•
•
Causes serial interface to enter COFA mode for one T1/E1 frame period
(125 µs)—not necessarily on a frame boundary.
For every activated channel transmitting an HDLC message, the Transmit
channel enters an abort state where the BLP transmits a repetitive abort
sequence of 16 consecutive 1s.
MUSYCC does not update the transmit Message Descriptor and does not
generate an EOB/EOM unless the message is already sent or the buffer is
already processed.
MUSYCC stops polling any active transmit channels descriptor.
After the COFA condition subsides, the channel is deactivated.
Channel Level Recovery Actions:
•
6.4.8.4 Receive Errors
Overflow Due to Host
Ownership of Buffer while
Receiving HDLC Message
(ONR)
100660E
Transmit channel reactivation is required.
Receive errors are service-affecting and require a corrective action by the host to
resume normal bit-level processing.
In the case of overflow due to host ownership of the buffer while receiving an
HDLC message, MUSYCC attempts to access the next Message Descriptor to
store a message or part of a message, and finds that ownership of the descriptor
has not been granted by the host.
This error results when currently receiving an HDLC message, and no
additional descriptors are available in a timely manner.
Conexant
6-37
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
Once a descriptor is granted, however, MUSYCC assumes ownership of the
message buffer and continues writing data until the end of buffer is reached. If the
host reclaims the buffer without MUSYCC granting ownership back to the host, a
host error occurs and the effects are indeterminate.
Reason:
•
Degradation of host subsystem or application software performance.
Effects:
•
•
•
•
•
Interrupt Descriptor in Interrupt Queue with ERROR = ONR, DIR = 0
(if MSKBUFF = 0 in Receive Channel Configuration Descriptor).
The received data in the internal FIFO buffer is discarded and lost to the
host.
The remainder of the HDLC message currently being received is
discarded.
The Receive Buffer Status Descriptor cannot be written.
The channel is deactivated.
Channel Level Recovery Actions:
•
•
Overflow Due to Internal FIFO
Buffer Overrun (BUFF)
Provide sufficient amount of shared memory to store received data using
the lists of Message Descriptors with ownership granted to MUSYCC.
Reactivate channel.
In the case of overflow due to internal FIFO buffer overrun, the internal FIFO
buffer has not been completely copied to shared memory before more data bits
arrive needing to be stored in the FIFO buffer. MUSYCC has access to a message
buffer space in shared memory in this case.
Reasons:
•
•
Degradation of host sub system performance.
Congestion of the PCI bus.
Effects:
•
•
•
•
•
•
•
6-38
The Interrupt Descriptor in Interrupt Queue with ERROR = BUFF,
DIR = 0 (if MSKBUFF = 0 in Receive Channel Configuration Descriptor).
The received data in the internal FIFO buffer is discarded and lost to the
host.
The remainder of HDLC message currently being received is discarded.
Access the Next Message Pointer from the Current Message Descriptor.
Return ownership of current Message Descriptor by writing the Receive
Buffer Status Descriptor with ONR = HOST, ERROR = BUFF (if
INHRBSD = 0 in Receive Channel Configuration Descriptor).
BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
Channel Level Recovery Actions:
•
•
•
If possible, increase internal FIFO buffer space for this channel. For this
action, the channel must be deactivated first.
If required, alleviate congestion of the PCI bus.
Change of Frame Alignment (COFA) while Receiving HDLC Message
(T1/E1 modes)
In the case of a Change of Frame Alignment while receiving an HDLC message
(T1/E1 modes), the RSYNC input signal transitions from low to high
unexpectedly by the “frame synchronization flywheel mechanism.” This error
applies only to ports configured for T1, E1, 2xE1, or 4xE1 signals. Frame
synchronization indicates the location of time slot 0 in the serial data stream.
Lacking frame synchronization, the received channelized data becomes unaligned
and unmappable. This error affects all active channels in the channel group.
Reason:
•
T1/E1 signal failure is detected by the physical interface providing the
serial data, clock frequency, and synchronization to the serial interface on
MUSYCC.
Effects:
•
•
•
•
•
•
•
Causes the serial interface to enter the COFA mode for one T1/E1 frame
period (125 µs).
For each activated channel receiving an HDLC message, the remainder of
the HDLC message currently being received is discarded, and the receiver
scans for the opening flag of the next HDLC message before attempting to
fill the channel’s FIFO buffer again.
For each activated channel receiving an HDLC message, the ownership of
the current Message Descriptor is granted back to the host by writing the
Receive Buffer Status Descriptor with ONR = HOST and
ERROR = COFA (if INHRBSD = 0 in Receive Channel Configuration
Descriptor).
After all activated channels are serviced, MUSYCC writes the Interrupt
Descriptor in Interrupt Queue with ERROR = COFA. DIR = 0
(if MSKCOFA = 0 in Group Configuration Descriptor).
After the COFA condition clears, normal bit-level operations continue.
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
•
100660E
None required.
Conexant
6-39
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
Out of Frame (OOF)
Out-of-frame or loss-of-frame indicates that the entire serial data stream is invalid
and data cannot be recovered from such a signal. In this case, out-of-frame of the
incoming signal occurred while in the midst of receiving an HDLC message and
copying the data to shared memory.
Reason:
•
MUSYCC writes the T1/E1 signal failure is detected by the physical
interface providing the serial data, clock frequency, and synchronization to
the serial interface on MUSYCC.
Effects:
•
•
•
•
•
•
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
ERROR = OOF, DIR = 0 (if MSKOOF = 0 in Group Configuration
Descriptor).
If bit field OOFABT = 0, BLP, and DMAC continue as if no errors
occurred and transfer received data into shared memory buffers normally.
If bit field OOFABT = 1 and is currently receiving an HDLC message, the
received data in the internal FIFO buffer is discarded and lost to the host.
DMAC accesses the Next Message Pointer from the current Message
Descriptor. MUSYCC returns ownership of the current Message
Descriptor by writing the Receive Buffer Status Descriptor with
ONR = HOST, ERROR = OOF (if INHRBSD = 0 in Receive Channel
Configuration Descriptor).
Regardless, the BLP continues scanning for opening flag.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Receive channel recovers automatically.
Channel Level Recovery Actions:
Frame Check
Sequence (FCS) Error
• None required.
In the case of an FCS error, the frame check sequence (or CRC) calculated for the
received HDLC message by MUSYCC does not match the FCS sent within the
HDLC message.
Reason:
•
Bit errors during transmission.
Effects:
•
•
•
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = FCS, DIR = 0
(if MSKMSG = 0 in Channel Configuration Descriptor).
The entire HDLC message already copied to shared memory buffers.
DMAC accesses the Next Message Pointer from the current Message
Descriptor.
Returns ownership of the current Message Descriptor to the host by
writing the Receive Buffer Status Descriptor with ONR = HOST,
ERROR = FCS (if INHRBSD = 0 in Channel Configuration Descriptor).
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
•
6-40
None required.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
Octet Alignment (ALIGN)
Error
6.4 Protocol Support
In the case of an Octet Alignment (ALIGN) error, the HDLC message size after
0-bit extraction is not a multiple of 8 bits.
Reasons:
•
•
Bit errors during transmission.
Incorrect transmission of HDLC messages from the distant end.
Effects:
•
•
•
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = ALIGN,
DIR = 0 (if MSKMSG = 0 in Receive Channel Configuration Descriptor).
The entire HDLC message is transferred to shared memory.
DMAC accesses the Next Message Pointer from the current Message
Descriptor.
Returns ownership of the current Message Descriptor to the host by
writing the Receive Buffer Status Descriptor with ONR = HOST,
ERROR = ALIGN (if INHRBSD = 0 in Receive Channel Configuration
Descriptor).
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
Abort Termination (ABT)
• None required.
In the case of an Abort Termination (ABT) error, the receiver detects an abort
sequence from the distant end. An abort sequence is defined as 0 followed by 7
consecutive 1s.
Reason:
•
The distant end can not complete transmission of HDLC message.
Effects:
•
•
•
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = ABT, DIR = 0
(if MSKMSG = 0 in Receive Channel Configuration Descriptor).
Partial HDLC message is transferred to shared memory.
DMAC accesses the Next Message Pointer from the current Message
Descriptor.
Returns ownership of the current Message Descriptor to the host by
writing the Receive Buffer Status Descriptor with ONR = HOST,
ERROR = ABT (if INHRBSD = 0 in Receive Channel Configuration
Descriptor).
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
•
100660E
None required.
Conexant
6-41
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
Long Message (LNG)
In the case of a Long Message (LNG) error, the received HDLC message size is
determined to be greater than the maximum allowed message size (per MAXSEL
in Channel Configuration Descriptor).
Reason:
•
Incorrect transmission of HDLC messages from the distant end.
Effects:
•
•
•
•
•
The Interrupt Descriptor in Interrupt Queue is ERROR = LNG, DIR = 0
(if MSKMSG = 0 in Receive Channel Configuration Descriptor).
DMAC accesses the Next Message Pointer from the current Message
Descriptor.
Returns ownership of the current Message Descriptor to the host by
writing the Receive Buffer Status Descriptor with ONR = HOST,
ERROR = LNG (if INHRBSD = 0 in Receive Channel Configuration
Descriptor).
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
•
Short Message (SHT)
None required.
In the case of a Short Message (SHT), the total received HDLC message size
(including FCS) is less than the number of FCS bits specified for the receive
channel. In other words, for a channel configured for 16-bit FCS, a minimum of
an 8-bit payload must be received to avoid a short message error. For this
example, three octets must be received—one octet for payload and two for FCS.
Receiving two octets would be considered a short message.
Reasons:
•
•
Bit errors during transmission.
Incorrect transmission of HDLC messages from the distant end.
Effects:
•
•
•
•
The Interrupt Descriptor in Interrupt Queue is ERROR = SHT, DIR = 0 (if
MSKIDLE = 0 in Receive Channel Configuration Descriptor).
Maintains ownership of current Message Descriptor.
The BLP resumes scanning for opening flag of the next HDLC message.
Simultaneously, MUSYCC checks for Message Descriptor ownership
before proceeding with bit-level operations.
Channel Level Recovery Actions:
•
6-42
None required.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
SS7 Signal Unit Error Rate
(SUERR) Interrupt
6.4 Protocol Support
In the case of an SS7 SUERR, an error is detected in SS7 mode which caused a
counter for SS7 related errors to equal or exceed the permitted threshold value.
The threshold is stored on a per-channel group basis in the bit field SUET in a
Group Configuration Descriptor.
Reasons:
•
•
•
•
NOTE:
A Short SS7 message increments the SS7 counter.
An FCS error in the SS7 message increments the SS7 counter.
An Octet alignment error in the SS7 message.
Accumulation of 16 “octet count” type errors increments counter.
Receiving 256 unerrored SS7 messages decrements the SS7counter.
Effects:
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = SUERR,
DIR = 0 (if MSKSUERR = 0 in Receive Channel Configuration
Descriptor).
The BLP scans for the opening flag of the next HDLC message.
Simultaneously, DMAC checks for Message Descriptor ownership before
transferring received data to shared memory.
Channel Level Recovery Actions:
•
None required.
6.4.9 Transparent Mode
MUSYCC supports a transparent mode where no distinction is made between
information and non-information bits in the data bit stream. This mode is
assigned on a per channel and direction basis by the bit field PROTOCOL in the
Channel Configuration Descriptor.
In transparent mode, the following characteristics apply:
•
•
•
All data bits are transferred between shared memory and the serial
interface without protocol support such as those listed for the HDLC
mode.
Host must maintain the necessary data transfer rates at all times by
providing Message Descriptors and data buffers for both the transmit and
receive channels.
The host must always set the bit field EOM to 0 in each Transmit Buffer
Descriptor. Setting EOM to 1 causes indeterminate results. Due to
EOM = 0, the other Transmit Buffer Descriptor bit fields—IC, PADEN,
PADCNT, and REPEAT—are ineffective.
Unlike HDLC mode, MUSYCC does not poll a host-owned Transmit Buffer
Descriptor during transparent mode.
When the internal buffer is empty and no more transmit data is available from
shared memory (i.e., host-owned buffer), MUSYCC does the following:
1.
2.
100660E
Issues an ONR error.
Enters the channel deactivate state, sending idle code on the affected
channel.
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
If the host wants to send any more data on that channel, the host must
reactivate any transparent mode transmit channel that has issued an ONR error.
Notice there is no mechanism for transparent mode channels to ever enter the
IDLE transmission state.
6.4.9.1 Transmit Events
Transmit events are informational and require no recovery actions.
End of Buffer (EOB)
Reason:
•
DMAC reached the end of a buffer by servicing a number of octets equal
to the BLEN bit field in a Transmit Buffer Descriptor. For the transparent
mode, EOM is not a valid event because there is no concept of messages.
Effects:
•
•
•
6.4.9.2 Receive Events
End of Buffer (EOB)
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
EVENT = EOB, DIR = 1 (per EOBI in Transmit Buffer Descriptor).
MUSYCC continues with normal transparent mode processing by
processing to the next message structure.
MUSYCC requires more data buffers.
Receive events are informational and require no recovery actions.
Reason:
•
BLP reached the end of a buffer by transferring into shared memory a
number of octets equal to the BLEN bit field in a Receive Buffer
Descriptor.
Effects:
•
Frame Recovery (FREC)
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
EVENT = EOB, DIR = 0 (per EOBI in Receive Buffer Descriptor).
Reason:
•
BLP detects that the serial interface transitions from an out-of-frame to an
in-frame condition.
Effects:
•
•
6-44
The Interrupt Descriptor in Interrupt Queue with EVENT = FREC,
DIR = 0 (per MSKOOF in Group Configuration Descriptor).
MUSYCC continues with normal transparent mode processing by
processing to the next message structure.
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4.9.3 Transmit Errors
Underflow Due to Host
Ownership of Buffer (ONR)
6.4 Protocol Support
Transmit Errors are service-affecting and require a corrective action by the host to
resume normal bit-level processing.
In the case of underflow due to host ownership of buffer (ONR), sufficient data
throughput from shared memory is not maintained to support the data rate of the
serial interface. That is, ownership of messages was not handed over to MUSYCC
in a timely manner.
Reason:
•
Degradation of the host subsystem or application software performance.
Effects:
•
•
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = ONR,
DIR = 1.
Data from Data Buffer not being read.
The Buffer Descriptor not overwriting the Buffer Status Descriptor.
No additional activity on the PCI bus for this channel direction.
Transmit channel activity is suspended.
Channel Level Recovery Actions:
•
Underflow Due to Internal
FIFO Buffer Under-Run
(BUFF)
Provide sufficient amount of data for transmission using lists of Message
Descriptors with ownership given to MUSYCC.
• Reactivate transmit channel.
In the case of underflow due to internal FIFO buffer under-run (BUFF), the
internal FIFO buffer becomes empty when MUSYCC must output data bits (at
the serial interface clock rate) and MUSYCC has ownership of a message buffer
in shared memory.
Reasons:
•
•
Degradation of the host subsystem or application software performance.
Congestion of the PCI bus.
Effects:
•
•
•
•
•
•
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
ERROR = BUFF, DIR = 1.
Continuous idle code transmission.
Data from data buffer not being read.
The Buffer Descriptor not overwriting the Buffer Status Descriptor.
No additional activity on the PCI bus for this channel direction.
Transmit channel activity is suspended.
Channel Level Recovery Actions:
•
•
100660E
Provide sufficient amount of data for transmission using lists of Message
Descriptors with ownership given to MUSYCC.
Reactivate transmit channel.
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4 Protocol Support
6.4.9.4 Receive Errors
Overflow Due to Host
Ownership of the Buffer
(ONR)
Receive errors are service-affecting and may require a corrective action by a
controlling device to resume normal bit-level processing.
In the case of overflow due to host ownership of the buffer, the host has not
provided sufficient data buffer space to store received data from the serial
interface, and the internal FIFO buffer overflows with received data bits.
Reasons:
•
•
Degradation of the host subsystem or application software performance.
Congestion of the PCI bus.
Effects:
•
•
•
The Interrupt Descriptor in Interrupt Queue with ERROR = ONR,
DIR = 0.
The received data in the internal FIFO buffer is discarded and lost to the
host.
The channel is deactivated.
Channel Level Recovery Actions:
Overflow Due to Internal FIFO
Buffer Overrun (BUFF)
• Reactivate the channel.
In the case of overflow due to internal FIFO buffer overrun, the internal FIFO
buffer is not completely copied to shared memory before more received data bits
must be stored in the FIFO buffer. MUSYCC has access to a shared memory
buffer in this case.
Reasons:
•
•
Degradation of the host subsystem or application software performance.
Congestion of the PCI bus.
Effects:
•
•
•
•
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
ERROR = BUFF, DIR = 0.
The received data in the internal FIFO is discarded and lost to the host.
No additional activity on the PCI bus for this channel direction.
Receive channel activity is suspended.
Channel Level Recovery Actions:
•
•
•
6-46
If possible, increase internal FIFO buffer space for this channel.
Alleviate loading of the PCI bus.
Reactivate receive channel with a channel activate or channel jump service
request or with a slave write into the Receive Channel Configuration
Table.
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
Change of Frame Alignment
(T1/E1 Modes) (COFA)
6.4 Protocol Support
In the case of a Change of Frame Alignment while receiving an HDLC message
(T1/E1 modes), the RSYNC input signal transitions from low to high
unexpectedly by the “frame synchronization flywheel mechanism.” This error
applies only to ports configured for T1, E1, 2xE1, or 4xE1 signals. Frame
synchronization indicates the location of time slot 0 in the serial data stream.
Lacking frame synchronization, the received channelized data becomes unaligned
and unmappable. This error affects all active channels in the channel group.
Reason:
•
A signal failure detected by the physical interface providing the serial data,
clock frequency, and synchronization to the serial interface on MUSYCC.
Effects:
•
•
•
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
ERROR = COFA, DIR = 0.
If OOFABT bit field is set to 0 in the Group Configuration Descriptor,
then continue channel activity. That is, received data bits are sampled and
eventually copied into shared memory.
If bit field OOFABT is set to 1 in the Group Configuration Descriptor,
suspend channel activity. Received data bits are discarded and lost to the
host processor.
Channel Level Recovery Actions:
•
Out of Frame (OOF)
If OOFABT = 1, once the received signal has recovered, reactivate receive
channel with a Channel Activate or Channel Jump Service Request or with
a slave write into the Receive Channel Configuration Table.
Out-of-frame or loss-of-frame indicates the entire serial data stream is invalid,
and data cannot be recovered from such a signal.
Reasons:
•
A signal failure detected by the physical interface providing the serial data,
clock frequency, and synchronization to the serial interface on MUSYCC.
Effects:
•
•
•
•
MUSYCC writes the Interrupt Descriptor in Interrupt Queue with
ERROR = OOF, DIR = 0.
The received data in the internal FIFO buffer is discarded and lost to the
host.
If OOFABT bit field is set to 0 in the Group Configuration Descriptor,
continue channel activity but transfer all 1s data into shared memory for
the duration of the OOF. When the OOF condition clears, normal bit-level
processing resumes automatically without host intervention.
If OOFABT bit field is set to 1 in the Group Configuration Descriptor,
channel activity suspends without transferring any data to shared memory.
Channel Level Recovery Actions:
•
100660E
When OOFABT selects receive message processing disabled, the host must
reactivate the receive channel after the OOF condition has cleared.
Reactivation is not required if OOFABT allows receive message
processing to continue.
Conexant
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6.0 Basic Operation
6.4 Protocol Support
Multichannel Synchronous Communications Controller (MUSYCC™)
6.4.10 Intersystem Link Protocol (ISLP)
ISLP is supported by setting the following bit field value referenced in
Table 5-18, Channel Configuration Descriptor:
FCS = 1, PROTOCOL = 2
6-48
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.5 Signaling System 7
6.5 Signaling System 7
6.5.1 SS7 Repeat Message Transmission
Signaling System 7 (SS7) requires the ability to continuously repeat a message
under certain circumstances. The Repeat Message Transmission section of this
document describes the repeat feature fully and is usable for an SS7 application.
6.5.2 Message Filtering
Message filtering is always enabled for a receive channel which is configured for
SS7-HDLC-CRC16 mode in Table 5-18, Channel Configuration Descriptor.
When receiving an unerrored message with a payload length of 3, 4, or 5
octets and the required 2-octet FCS, MUSYCC transfers the data into the memory
buffer as usual and then enters the message filtering mode. This mode does not
apply to messages with payloads greater than 5 octets.
In this mode, the next Message Descriptor is processed in the normal manner
(receive Buffer Status Descriptor is written, next pointer is used to read next
Message Descriptor, ONR and NP bits are checked, and so on). In this case, the
current memory buffer is not filled until MUSYCC exits the message filtering
mode.
The 3-, 4-, or 5-octet payload and the 2-octet FCS are stored inside MUSYCC
and are considered golden messages by being 3, 4, or 5 octets long. Subsequent
received messages are compared to this message.
Each bit of the subsequent message will be compared bit-wise to the contents
of the golden message. The following can occur:
•
•
If a match occurs, the payload and FCS of the golden message match the
current message before a closing flag is received for the current message.
The maskable interrupt MSKSFILT is generated to the host. MUSYCC
remains in message filtering mode, and the golden message is retained.
If a mismatch occurs, a bit-wise mismatch is detected between a bit in the
golden message and the corresponding bit in the current message before a
closing flag is received for the current message. MUSYCC immediately
exits the filter mode.
The treatment for the current message becomes a normal message treatment.
If the current message is unerrored and qualifies to become a golden message, it
is transferred to the current Receive Data Buffer and becomes the new golden
message internally to MUSYCC.
If the current message is unerrored and greater than 6 octets total, it cannot
become a golden message, and MUSYCC continues normal message treatment.
100660E
Conexant
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.5 Signaling System 7
6.5.3 Signal Unit Error Rate Monitoring
The Signal Unit Error Rate Monitor (SUERM) facility provides a 6-bit counter
which serves as a real-time figure-of-merit for the receive link integrity. It is
incremented and decremented in a “leaky-bucket” style, based upon integration
of good message and bad octet periods on the receive channel.
6.5.4 SUERM Counter Incrementing
The SUERM counter increments when any signal unit error occurs. A signal unit
error is defined as one of the following events:
•
•
•
•
SHT:
Short Frame error
ALIGN: Octet Alignment error
CRC:
FCS Mismatch error
Accumulation of 16 octet count errors
Short Frame errors, Octet Alignment errors, or CRC/FCS Mismatch errors
generate a maskable interrupt, SHT, LNG, CRC respectively, toward the host and
cause the SUERM counter to be incremented. Each time the SUERM counter is
incremented, the maskable interrupt SINC is generated to the host indicating this
condition.
6.5.5 SUERM Octet Counting
Octet counting mode is entered if seven consecutive 1s are detected (abort
condition), or the received message length exceeds the selected maximum
received-frame length register value (long frame error)
When in Octet counting mode, a 4-bit bad octet counter is incremented for
every received octet until a condition is met to exit this mode. As the counter rolls
over from 15 to 0, the SUERM counter is incremented by one. This mode is
exited when a correctly checked signal unit (unerrored message) is detected.
Each time the octet counting mode is entered, the value of 4-bit bad octet
counter is reset.
6.5.6 SUERM Counter Decrementing
The SUERM counter is decremented when 256 unerrored messages are received.
An unerrored message indicates that a short frame or long frame error was not
detected, no octet alignment error was detected, and no CRC error was detected.
Each unerrored message increments an 8-bit good message counter. When this
counter rolls over from 255 to 0, the SUERM counter is decremented by one.
While in octet counting mode, the value of the 8-bit good message counter is
maintained from the last non-octet counting mode and starts to increment again
from that value when a good message causes an exit from the octet counting
mode.
When the SUERM counter decrements, the maskable interrupt SDEC is
generated to the host indicating this condition.
6-50
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6.0 Basic Operation
Multichannel Synchronous Communications Controller (MUSYCC™)
6.6 Self-Servicing Buffers
6.6 Self-Servicing Buffers
The transmit and receive Buffer Descriptors and Buffer Status Descriptors are
designed to facilitate a mechanism known as “self-servicing buffers.” This
mechanism allows the host to configure MUSYCC to fill a linked list of data
buffers as it receives a complete message through a receive channel, and empty
that same list of data buffers through a transmit channel without any further host
intervention.
The mechanism works as follows:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
NOTE:
100660E
Host initializes linked list of Message Descriptors in shared memory.
Host configures receive channel to point to first Message Descriptor.
Host configures transmit channel to point to the same Message Descriptor.
The OWNER bit field in the Buffer Descriptor in the Message Descriptor
is set to 0. Therefore, for the transmitter, the buffer is owned by the host;
for the receiver, the buffer is owned by MUSYCC.
Both receive and transmit channel are activated.
As the receiver detects a valid incoming message, it begins filling the first
data buffer from the linked list. The transmitter remains idle, polling the
OWNER bit in the Transmit Buffer Descriptor.
As the receiver fills the first buffer, it writes the Receive Buffer Status
Descriptor (and sets OWNER to 1) and moves to the Next Message Pointer
which identifies the next Receive Data Buffer on the linked list.
The transmit channel detects the OWNER set to 1 for the first Transmit
Data Buffer, assumes ownership of the buffer, and begins emptying data to
the serial port.
Upon detecting the end of a message, the receiver writes the Receive
Buffer Status Descriptor and marks this last buffer as containing the End of
Message and sets the buffer length field, BLEN to indicate the amount of
data received in this last buffer.
When the transmitter detects the End of Message marking in the last
buffer, the transmitter sends the final BLEN amount of data out the serial
port and writes the Transmit Buffer Status Descriptor (and sets OWNER
to 0) and moves into the idle state again.
Go to step 6 to continue processing the next message.
For self-servicing buffers, the host need not write to any descriptors for
receive or transmit operations. MUSYCC writes the Receive Buffer Status
Descriptor, which is subsequently used as the Transmit Buffer Descriptor.
Conexant
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6.0 Basic Operation
6.6 Self-Servicing Buffers
6-52
Multichannel Synchronous Communications Controller (MUSYCC™)
Conexant
100660E
7
7.0 Electrical and Mechanical
Specifications
7.1 Electrical and Environmental Specifications
7.1.1 Absolute Maximum Ratings
Stressing the device parameters above absolute maximum ratings may cause permanent damage to the
device. This is a stress rating only. Functional operation of the device at these or any other conditions beyond
those listed in the operational sections of this specification is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect device reliability.
Table 7-1. Absolute Maximum Ratings
Parameter
Symbol
Value
Unit
Vdd, Vddo
–0.5 to 4.6
V
Continuous Power Dissipation
Pd
750
mW
Operating Junction Temperature
Tjc
125
°C
Storage Temperature
Ts
–55 to +125
°C
5 V–Tolerant Supply
VGG
–0.5 to 6
V
Core Supply
VDDC
–0.5 to 3.3
V
5 V–Tolerant DC Input
Input, Hi–Z
Out
–0.5 to VGG + 0.5
(not to exceed 6 V)
V
5 V–Tolerant DC Output
Output Lo-Z
–0.5 to Vdd + 0.5
(not to exceed 4.6 V)
V
Supply Voltage
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Conexant
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7.0 Electrical and Mechanical Specifications
7.1 Electrical and Environmental Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.1.2 Recommended Operating Conditions
Table 7-2. Recommended Operating Conditions
Parameter
Supply Voltage
Symbol
Value
Unit
Vddi, Vddo
3.0 to 3.6
V
–40 to +85
°C
Ambient Operating Temperature
EPF
Tac
High-Level Input Voltage
Vih
2.0 to VGG + 0.3
V
Low-Level Input Voltage
Vil
–0.3 to 0.8
V
High-Level Output Current Source
Ioh
200 to 400
µA
Low-Level Output Current Sink
Iol
2 to 3
mA
Output Capacitive Loading
Cld
60
pF
5 V Tolerant Supply(1)
VGG
4.75 to 5.25
V
Core Supply
VDDC
2.3 to 2.7
V
Symbol
Value
Unit
High-Level Output Voltage
Voh
2.4
V
Low-Level Output Voltage
Vol
0.4
V
Input Leakage Current
Il
–1 to 1
µA
Three-state Leakage Current
Ioz
–10 to 10
µA
Resistive Pullup Current
Ipr
100 to 500
µA
Supply Current
Idd
130
µA
NOTE(S):
(1) V
GG
input can be supplied by VDD in the 3.3 V signaling environment.
7.1.3 Electrical Characteristics
Table 7-3. Electrical Operating Characteristics
Parameter
7-2
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7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
7.2 Timing and Switching Specifications
7.2.1 Overview
The major subsystems of MUSYCC are the host interface, the expansion bus
interface, and the serial interface. The host interface is PCI compliant. For other
references to PCI, see the PCI Local Bus Specification, Revision 2.1, June 1,
1995. The expansion bus and serial bus interfaces are similar to the host interface
timing characteristics; the differences and specific characteristics common to
either interface are further defined.
7.2.2 Host Interface (PCI) Timing and Switching Characteristic
Reference the PCI Local Bus Specification, Revision 2.1, June 1, 1995 for
information on:
•
•
•
•
•
•
Indeterminate inputs and metastability
Power requirements, sequencing, decoupling
PCI DC specifications
PCI AC specifications
PCI V/I curves
Maximum AC ratings and device protection
Table 7-4. PCI Interface DC Specifications (1 of 2)
Symbol
VDDi, VDDo
Parameter
Condition
Min
Max
Unit
3.6
V
VGG + 0.5
V
0.3VDD
V
Supply Voltage
—
3.0
Vih
Input High Voltage
—
0.5VDD
Vil
Input Low Voltage
—
Vipu
Input Pull-up Voltage(1)
—
0.7VDD
—
V
Iil
Input Leakage Current(2)
0 < Vin < VDD
—
±10
µA
Iout = –500 µA
0.9VDD
—
V
Voh
100660E
Output High Voltage
Conexant
–0.5
7-3
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7.0 Electrical and Mechanical Specifications
7.2 Timing and Switching Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
Table 7-4. PCI Interface DC Specifications (2 of 2)
Symbol
Parameter
Condition
Min
Max
Unit
Iout = 1500 µA
—
0.1 VDD
V
Vol
Output Low Voltage(3)
Cin
Input Pin Capacitance(4)
—
—
10
pF
Cclk
CLK Pin Capacitance
—
5
12
pF
IDSEL Pin Capacitance(5)
—
—
8
pF
Pin Inductance(6)
—
—
20
nH
CIDSEL
Lpin
NOTE(S):
(1)
(2)
(3)
(4)
(5)
(6)
Guaranteed by design. It is the minimum voltage to which pull-up resistors are calculated to pull a floated network.
Applications sensitive to static power utilization should ensure that the input buffer is conducting minimum current at this
input voltage.
Input leakage currents include hi-Z output leakage for all bidirectional buffers with three-state outputs.
Signals without pull-up resistors must have 3 mA low output current. Signals requiring pull-up must have 6 mA; the latter
includes FRAME*, TRDY*, IRDY*, DEVSEL*, STPP*, SERR*, and PERR*
Absolute maximum pin capacitance for a PCI input is 10 pF (except for CLK) with an exception granted to motherboard-only
devices, which could be up to 16 pF, in order to accommodate PGA packaging. This would mean, in general, that components
for expansion boards would need to use alternatives to ceramic PGA packaging – i.e., PQFP, SGA, etc.
Lower capacitance on this input-only pin allows for non-resistive coupling to AD[xx].
This is a recommendation, not an absolute requirement. The actual value should be provided with the component data sheet.
Table 7-5. PCI Clock (PCLK) Waveform Parameters, 33 MHz PCI Clock
Symbol
Parameter
Min
Max
Unit
Tcyc
Clock Cycle Time(1)
30
—
ns
Thigh
Clock High Time
11
—
ns
Tlow
Clock Low Time
11
—
ns
–
Clock Slew Rate(2)
1
4
V/ns
Vptp
Peak-to-Peak Voltage
0.4 Vdd
—
V
NOTE(S):
(1)
(2)
7-4
MUSYCC works with any clock frequency between DC and 66 MHz, nominally. The clock frequency can be changed at any
time during operation of the system as long as clock edges remain monotonic, and minimum cycle and high and low times
are not violated. The clock can only be stopped in a low state.
Rise and fall times are specified in terms of the edge rate measured in V/ns. This slew rate must be met across the minimum
peak-to-peak portion of the clock waveform.
Conexant
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7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Table 7-6. PCI Clock (PCLK) Waveform Parameters, 66 MHz PCI Clock
Symbol
Parameter
Min
Max
Unit
Tcyc
Clock Cycle Time(1)
15
—
ns
Thigh
Clock High Time
6
—
ns
Tlow
Clock Low Time
6
—
ns
—
Clock Slew Rate(2)
1
4
V/ns
Vptp
Peak-to-Peak Voltage
0.4 Vdd
—
V
NOTE(S):
(1)
(2)
MUSYCC works with any clock frequency between DC and 66 MHz, nominally. The clock frequency can be changed at any
time during operation of the system as long as clock edges remain monotonic, and minimum cycle and high and low times
are not violated. The clock can only be stopped in a low state.
Rise and fall times are specified in terms of the edge rate measured in V/ns. This slew rate must be met across the minimum
peak-to-peak portion of the clock waveform.
Figure 7-1. PCI Clock (PCLK) Waveform
0.6 Vdd
0.5Vdd V
Vptp
min
0.4Vdd
0.3Vdd
0.2 Vdd
Thigh
Tlow
Tcyc
8478_023
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7.0 Electrical and Mechanical Specifications
7.2 Timing and Switching Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
Table 7-7. PCI Reset Parameters
Symbol
Parameter
Min
Max
Unit
Trst
Reset Active Time after
Power Stable
1
—
ms
Trst_clk
Reset Active Time after
Clock Stable
100
—
µs
Vnom
Nominal Voltage Level(1)
—
—
V
—
RST* Slew Rate(2)
50
—
mV/ns
Tfail
Power Failure Detect Time(3)
—
—
—
Trst-off
Reset Active to Float Delay
—
40
ns
NOTE(S):
(1)
(2)
(3)
The nominal voltage level refers to a voltage test point in the power-up curve where the system can declare start of a “power
good” signal.
The minimum RST* slew rate applies only to the rising (deassertion) edge of the reset signal, and ensures that system noise
cannot render an otherwise monotonic signal to appear to bounce in the switching range.
The value of Tfail is the minimum of
a. 500 ns (max) from power rail going out of specification by exceeding specified tolerances by more than 500 mV.
b. 100 ns (max) from 5 V rail falling below 3.3 V rail by more than 300 mV.
Figure 7-2. PCI Reset Timing
Power
Power
Fail
Vnom
Tfail
PCLK
100 ms (typ)
PWR_GOOD
Trst
PRST*
Trst-clk
PCI
Signals
Trst-off
Three-state
8478_025
7-6
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7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Table 7-8. PCI I/O Timing Parameters, 33 MHz PCI Clock
Symbol
Parameter
Min
Max
Unit
Tval
PCLK to Signal Valid Delay—Bused Signal(1, 2, 4)
2
11
ns
Tval (ptp)
PCLK to Signal Valid Delay—Point To Point(1, 2)
2
12
ns
Ton
Float to Active Delay(3)
—
13
ns
Toff
Active to Float Delay(3)
—
28
ns
Tds
Input Setup Time to Clock—Bused Signal(2)
7
—
ns
Tsu (ptp)
Input Setup Time to Clock—Point To Point(2)
10, 12
—
ns
Tdh
Input Hold Time from Clock(5)
0
—
ns
NOTE(S):
(1)
(2)
(3)
(4)
(5)
Minimum and maximum times are evaluated at 80 pF equivalent load. Actual test capacitance may vary, and results should
be correlated to these specifications.
REQ* and GNT* are the only point-to-point signals and have different output valid delay and input setup times than bused
signals. GNT* has a setup of 10; REQ* has a setup of 12.
For purposes of active/float timing measurements, the high-Z or off state is when the total current delivered through the
component pin is less than or equal to the leakage current specification at 80 pF equivalent load.
TVAL = 17 ns max for INTA.
Tdh = 0.5 ns min for GNT, IDSEL, and IRDY.
Table 7-9. PCI I/O Timing Parameters, 66 MHz PCI Clock
Symbol
Parameter
Min
Max
Units
Tval
PCLK to Signal Valid Delay—Bused Signal(1, 2)
2
6
ns
Tval (ptp)
PCLK to Signal Valid Delay—Point To Point(1, 2)
2
6
ns
Ton
Float to Active Delay(3)
2
—
ns
Toff
Active to Float Delay(3)
—
14
ns
Tds
Input Setup Time to Clock—Bused Signal(2)
3
—
ns
Tsu (ptp)
Input Setup Time to Clock—Point To Point(2)
5
—
ns
Tdh
Input Hold Time from Clock
0
—
ns
NOTE(S):
(1)
(2)
(3)
Minimum and maximum times are evaluated at 80 pF equivalent load. Actual test capacitance may vary, and results should
be correlated to these specifications.
REQ* and GNT* are the only point-to-point signals and have different output valid delay and input setup times than bused
signals. GNT* has a setup of 10; REQ* has a setup of 12.
For purposes of active/float timing measurements, the high-Z or off state is when the total current delivered through the
component pin is less than or equal to the leakage current specification at 80 pF equivalent load.
100660E
Conexant
7-7
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Table 7-10. PCI I/O Measure Conditions
Symbol
Parameter
Value
Unit
Vth
Voltage Threshold High(1)
0.6 Vdd
V
Vtl
Voltage Threshold Low(1)
0.2 Vdd
V
Vtest
Voltage Test Point
0.4 Vdd
V
Vmax
Maximum Peak-to-Peak(2)
0.4 Vdd
V
—
Input Signal Edge Rate
1
V/ns
NOTE(S):
(1)
(2)
The input test is done with 0.1 Vdd of overdrive (over Vih and Vil). Timing parameters must be met with no more overdrive
than this. Production testing can use different voltage values, but must correlate results back to these parameters.
Vmax specifies the maximum peak-to-peak voltage waveform allowed for measuring input timing. Production testing can use
different voltage values, but must correlate results back to these parameters.
Figure 7-3. PCI Output Timing Waveform
Vth
PCLK
Vtest
Vtl
Tval
Output
Delay
Vtest
Output Current ≤ Leakage Current
Three-state
Output
Ton
Toff
8478_026
7-8
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-4. PCI Input Timing Waveform
Vth
CLK
Vtl
Tdh
Tds
Vth
Input
Inputs
Valid
Vtest
Vtl
Vmax
Vtest
8478_027
Figure 7-5. PCI Read Multiple Operation
PCLK
1
2
3
4
5
6
7
8
FRAME*
CBE[3:0]
Command
AD[31:0]
Address
Byte Enable
BE
Data 1
Data 2
PAR
IRDY*
TRDY*
DEVSEL*
8478_028
100660E
Conexant
7-9
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-6. PCI Write Multiple Operation
PCLK
1
2
3
4
5
6
FRAME*
CBE[3:0]
Command
BE
BE
AD[31:0]
Address
Data 1
Data 2
2
3
PAR
IRDY*
TRDY*
DEVSEL*
8478_029
Figure 7-7. PCI Write Single Operation
PCLK
1
4
FRAME*
CBE[3:0]
Command
BE
AD[31:0]
Address
Data 1
PAR
IRDY*
TRDY*
DEVSEL*
8478_030
7-10
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
7.2.3 Expansion Bus (EBUS) Timing and Switching Characteristic
The EBUS timing is derived from the PCI clock (PCLK) input to MUSYCC. The
ECLK output is either one-half of the PCI clock (M66EN = 1) or the same as the
PCI clock (M66EN = 0); the ECLK and PCLK relationship is shown in
Figures 7-8 and 7-9.
The EBUS I/O timing characteristics are identical to the PCI I/O timing
characteristics.
The EBUS clock waveform characteristics are identical to the PCI clock
waveform characteristics (refer to Tables 7-11 through 7-13 and Figures 7-10
through 7-12).
Figure 7-8. ECLK to PCLK Relationship (M66EN = 0)
Vth
PCLK
Vtest
Vtl
ECLK
Vtest
Vtl
Tde
8478_031
Figure 7-9. ECLK to PCKL Relationship (M66EN = 1)
PCLK
ECLK
Tde
8478_031a
Table 7-11. EBUS Reset Parameters
Symbol
Toff
Parameter
Active to Inactive Delay(1)
Min
Max
Units
—
30
ns
NOTE(S):
(1)
For purposes of active/float timing measurements, the high-Z or off state is when the total current delivered through the
component pin is less than or equal to the leakage current specification.
100660E
Conexant
7-11
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
7.2 Timing and Switching Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
Figure 7-10. EBUS Reset Timing
PCI
Reset
Reset Period
Toff
EBUS
Three-state
Output
Three-state
EBUS
Input
Input Ignored
8478_032
NOTE(S): The EBUS reset is dependent on the PRST* (PCI Reset) signal being asserted low.
Table 7-12. EBUS I/O Timing Parameters
Symbol
Parameter
Min
Max
Units
Tval
PCI Clock Fall to Signal Valid Delay—Bused
Signal(1)
2
15
ns
Tval (ptp)
PCI Clock Fall to Signal Valid Delay—Point To
Point(1)
2
15
ns
Ton
Float to Active Delay(2)
—
30
ns
Toff
Active to Float Delay(2)
—
30
ns
Tds
Input Setup Time to Clock—Bused Signal
3
—
ns
Tds (ptp)
Input Setup Time to Clock—Point To Point
3
—
ns
Tdh
Input Hold Time from Clock
7
—
ns
Tde
PCI Clock Fall to ECLK rising edge
—
7
ns
NOTE(S):
(1)
(2)
7-12
Minimum and maximum times are evaluated at 80 pF equivalent load. Actual test capacitance may vary, and results should
be correlated to these specifications.
For purposes of active/float timing measurements, the hi-z or off state is when the total current delivered through the
component pin is less than or equal to the leakage current specification at 80 pF equivalent load.
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Table 7-13. EBUS I/O Measure Conditions
Symbol
Parameter
Value
Units
Vth
Voltage Threshold High(1)
0.6 Vdd
V
Vtl
Voltage Threshold Low(1)
0.2 Vdd
V
Vtest
Voltage Test Point
0.4 Vdd
V
Vmax
Maximum Peak-to-Peak(2)
0.4 Vdd
V
—
Input Signal Edge Rate
1
V/ns
NOTE(S):
(1)
(2)
The input test for the 3.3 V environment is done with 0.1 Vdd of overdrive (over Vih and Vil). Timing parameters must be met
with no more overdrive than this. Production testing can use different voltage values, but must correlate results back to these
parameters.
Vmax specifies the maximum peak-to-peak voltage waveform allowed for measuring input timing. Production testing can use
different voltage values, but must correlate results back to these parameters.
Figure 7-11. EBUS Output Timing Waveform
Vth
PCLK
Vtest
Vtl
Tval
Output
Delay
Vtest
8478_033
Figure 7-12. EBUS Input Timing Waveform
Vth
PCLK
Vtest
Tds
Vth
Input
Vtl
Vtest
Vtl
Tdh
Vtest
Vmax
8478_034
100660E
Conexant
7-13
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
7.2.4 EBUS Arbitration Timing
Illustrated in Figures 7-13 and 7-14 are Intel- and Motorola-style write and read
transactions.
Figure 7-13. EBUS Write/Read Transactions, Intel-Style
See Notes
1
2
3
4
5
6
7
8
9
10
ECLK
HOLD
HLDA
EAD[31:0]
EBE[3:0]*
Address
Data
Byte Enables from PCI Data Phase
ALE
RD* (write)
WR* (write)
RD* (read)
WR* (read)
ALAPSE = 0
ELAPSE = 0
BLAPSE = 0
8478_035
NOTE(S):
1. HLDA assertion depends on the external bus arbiter. While HOLD and HLDA are both deasserted, MUSYCC places shared
EBUS signals in high impedance (three-state, shown as dashed lines).
2. MUSYCC outputs valid command bus signals: EBE, ALE, RD*, and WR* 1 ECLK cycle after HLDA assertion.
3. MUSYCC outputs valid EAD address signals, 2 ECLK cycles after HLDA assertion.
4. ALE assertion occurs 3 ECLK cycles after HOLD and HLDA are both asserted.ALAPSE inserts a variable number of ECLK
cycles to extend ALE high pulse width and EAD address interval.
5. EAD address remains valid for 1 ECLK cycle after ALE falling edge. During a write transaction, MUSYCC outputs valid EAD
write data 1 ECLK prior to WR* assertion. During a read transaction, EAD data lines are inputs.
6. ELAPSE inserts a variable number of ECLK cycles to extend RD*/WR* low pulse width and EAD data intervals. Read data
inputs are sampled on ECLK rising edge coincident with RD* deassertion.
7. EAD write data and EBE byte enables remain valid for 1 ECLK cycle after RD*/WR* deassertion.
8. HOLD is deasserted, and the bus is parked (command bus deasserted, EAD tristate) 1 ECLK after RD* or WR* deassertion.
The bus parked state ends when HLDA is deasserted, 1 ECLK after RD* or WR* deassertion.
9. Command bus is unparked (three-stated) one ECLK after HLDA deassertion; two different unpark phases are shown,
indicating the dependence on HLDA deassertion. If HLDA remained asserted until the next bus request, then command bus
remains parked until 1 ECLK cycle following the next HOLD assertion. Warning: Whenever HLDA is deasserted, all shared
EBUS signals are forced to three-state after 1 ECLK cycle, regardless of whether the EBUS transaction was completed.
MUSYCC will not reissue or repeat such an aborted transaction.
10. BLAPSE inserts a variable number of ECLK cycles to extend HOLD deassertion interval until the next bus request.
7-14
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-14. EBUS Write/Read Transactions, Motorola-Style
See Notes
1
2
3
4
5
6
7
8
9
10
ECLK
BR*
BG*
BGACK*
EAD[31:0]
EBE[3:0]*
Address
Data
Byte Enables from PCI Data Phase
AS*
R/WR* (read)
R/WR* (write)
DS*
8478_036
ALAPSE = 0
ELAPSE = 0
BLAPSE = 0
NOTE(S):
1. BG* assertion depends on the external bus arbiter. While BG* and BR* are both deasserted, MUSYCC places shared
EBUS signals in high impedance (three-state, as shown by dashed lines).
2. One ECLK cycle after BG* assertion, MUSYCC outputs valid command bus signals: EBE, AS*, R/WR*, and DS*.
3. Two ECLK cycles after BG* assertion, MUSYCC outputs valid EAD address signals. BGACK* assertion occurs three ECLK
cycles after BG* and BR* are both asserted.
4. ALAPSE inserts a variable number of ECLK cycles to extend AS* high pulse width and EAD address interval.
5. EAD address remains valid for one ECLK cycle after AS* falling edge. During a write transaction, MUSYCC asserts R/WR*
and outputs valid EAD write data one ECLK prior to DS* assertion. During a read transaction, EAD data lines are input.
6. ELAPSE inserts a variable number of ECLK cycles to extend DS* low pulse width and EAD data interval. Read data inputs
are sampled on ECLK rising edge coincident with DS* deassertion.
7. EAD write data, EBE, R/WR*, and AS* signals remain valid for one ECLK cycle after BGACK* and DS* are deasserted.
8. One ECLK cycle after BGACK* deassertion, the BR* output is deasserted and the bus is parked (command bus deasserted,
EAD three-state). The bus parked state ends when the external bus arbiter deasserts BG*.
9. Command bus is unparked (three-stated) one ECLK after BG* deassertion; two different unpark phases are shown,
indicating the dependence on BG* deassertion. If BG* remained asserted until the next bus request, then command bus
remains parked until one ECLK following the next BR* assertion. Warning: Whenever BG* is deasserted, all shared EBUS
signals are forced to three-state after one ECLK cycle, regardless of whether the EBUS transaction was completed.
MUSYCC will not reissue or repeat such an aborted transaction.
10. BLAPSE inserts a variable number of ECLK cycles to extend BR* deassertion interval until the next bus request.
100660E
Conexant
7-15
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
7.2.5 Serial Interface Timing and Switching Characteristics
Serial interface timing and switching characteristics are provided in Tables 7-14
through 7-17 and Figures 7-15 through 7-18.
Table 7-14. Serial Interface Clock (RCLK, TCLK) Parameters
Symbol
Parameter
Min
Max
Units
Fc
Clock Frequency
DC
8.192 ±10%
MHz
Tr
Clock Rise Time
—
2
ns
Tf
Clock Fall Time
—
2
ns
Min
Max
Units
Figure 7-15. Serial Interface Clock (RCLK,TCLK) Waveform
1/Fc
RCLK, TCLK
Tr
Tf
8478_037
Table 7-15. Serial Interface I/O Timing Parameters
Symbol
Parameter
Tval
Clock to Signal Valid Delay
2
20
ns
Tds
Data Setup Time
10
—
ns
Tdh
Data Hold Time
10
—
ns
Min
Max
Units
Table 7-16. Serial Interface Clock Hysteresis (RCLK, TCLK, with Schmitt Trigger)
Symbol
Parameter
VTH
High Threshold Voltage
0.7* VDDi
—
V
VTL
Low Threshold Voltage
0
0.3* VDDi
V
VH
Hysteresis
0.3
—
V
7-16
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-16. Serial Interface Clock (RCLK,TCLK) Waveform
Vth
8478_037a
RCLK, TCLK
Vh
Vtl
Table 7-17. Serial Interface I/O Measure Conditions for 3.3 V Signaling
Symbol
Parameter
Value
Units
Vth
Voltage Threshold High(1)
0.6 Vdd
V
Vtl
Voltage Threshold Low(1)
0.2 Vdd
V
Vtest
Voltage Test Point
0.4 Vdd
V
Vmax
Maximum Peak-to-Peak(2)
0.4 Vdd
V
—
Input Signal Edge Rate
1
V/ns
NOTE(S):
(1)
(2)
The input test for the 3.3 V environment is done with 0.1 Vdd of overdrive (over Vih and Vil). Timing parameters must be met
with no more overdrive than this. Production testing can use different voltage values, but must correlate results back to these
parameters.
Vmax specifies the maximum peak-to-peak voltage waveform allowed for measuring input timing. Production testing can use
different voltage values, but must correlate results back to these parameters.
Figure 7-17. Serial Interface Data Input Waveform
Vth
RCLK, TCLK
Vtest
Vtest
Tds
Vth
TSYNC, RSYNC, ROOF, RDAT
(Rising Edge)
Vtest
Vtl
Tval
Vtl
Tdh
Vtest
Vmax
Tval
Tds
Vth
Vtest
Vtest
Vtl
Vmax
8478_038
TSYNC, RSYNC, ROOF, RDAT
(Falling Edge)
Tdh
100660E
Conexant
7-17
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-18. Serial Interface Data Delay Output Waveform
TCLK
Vth
Vtest
Vtest
Vtl
Tval
Vth
TDAT
(Rising Edge)
Vtl
Vtest
Vtest
Vmax
Vtest
Vmax
Tval
Vth
TDAT
(Falling Edge)
Vtest
8478_039
Vtl
7.2.6 Package Thermal Specification
Table 7-18 lists the package thermal specifications.
Table 7-18. MUSYCC Package Thermal Resistance Characteristics
Package
Mounting
Conditions
Airflow–LFM (LMS)
0 (0.000)
50 (0.256)
100 (0.505)
200 (1.01)
400 (2.03)
Thermal Resistance (junction to ambient) = **C/W
208-BGA
Board-Mounted
26
22
19
18
17
208-Pin Quad
Flat Pack
Board–Mounted
21
19
17
16
14
208-Pin Quad
Flat Pack
Socket
23
21
19
18
16
NOTE(S):
1. LFM–linear feet per minute.
2. LMS–linear meters per second.
3. Junction to case temperature (°C): Tjc = T ac + ( θ ja × P d ) .
Tjc = θja x Pd(measured) + Tac(measured)
Where: Tjc = Junction Temperature (see Table 7-1).
θja = Thermal Resistance (θ-ja, see Table 7-18).
Tac = Ambient Case Temperature (see Table 7-2).
Pd = Power Dissipation = Vdd x Idd (Table 7-1).
7-18
Conexant
100660E
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
7.2.7 Mechanical Specifications
Figures 7-19 and 7-20 illustrate the mechanical specifications.
Figure 7-19. 208-Pin Metric Quad Flatpack (MQFP)
208 MQFP
TOP VIEW
BOTTOM VIEW
D
D1
D3
PIN #1
b
E3 E
E1
e
A
A2
S
Y
M
B
O
L
ALL DIMENSIONS IN MILLIMETERS
MIN.
NOM.
MAX.
4.07
A
----
3.70
A1
0.25
0.33
----
A2
3.20
3.37
3.60
D
30.60 BSC.
D1
28.00 BSC.
D3
25.50 REF.
E
30.60 BSC
E1
28.00 BSC.
E3
L
A1
e
L
0.60
0.75
0.50 BSC.
0.17
0.22
0.27
8478_040
b
1.30 REF.
100660E
25.50 REF.
0.50
Conexant
7-19
CN8478/CN8474A/CN8472A/CN8471A
7.0 Electrical and Mechanical Specifications
Multichannel Synchronous Communications Controller (MUSYCC™)
7.2 Timing and Switching Specifications
Figure 7-20. 208-Pin Plastic Ball Grid Array (PBGA)
A1 BALL PAD
CORNER
17.00
0.70
15.00 +
– 0.50
+ 0.10
0.50 – 0.10
17.00
0.70
15.00 +
– 0.50
30˚ TYP
0.80 ± 0.05
SEATING
PLANE
1.76 ± 0.21
45˚ CHAMFER
4 PLACES
0.40 ± 0.10
A1 BALL PAD
CORNER
0.56 ± 0.06
16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
T
1.00 REF
1.00 REF
1.00 REF
1.00 REF
0.50 R
3 PLACES
8478_048
7-20
Conexant
100660E
8
8.0 Terms, Definitions, and
Conventions
This document assumes the reader is familiar with the design and development of
PCI systems software and hardware, and with the message layout used in the
HDLC protocol. Most of the PCI reference material is located in the PCI Local
Bus Specification, Revision 2.1, June 1, 1995.
8.1 Applicable Specifications
The following documents were used as reference material for MUSYCC and this
document.
•
•
•
•
•
•
•
100660E
PCI Local Bus Specification
Revision 2.1, Version, June 1, 1995
ITU-T Recommendation Q.921 (03/93)
Digital Subscriber Signaling System No. 1
ITU-T Recommendation Q.703 (03/93)
Specification of Signaling System No. 7
ANSI T1.408-1990
ITU-T Recommendation G.704
IEEE Standard 1149.1-1990
Brooktree Bt8370 Specification
Conexant
8-1
CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
8.2 Numeric Notation
Multichannel Synchronous Communications Controller (MUSYCC™)
8.2 Numeric Notation
The general representation for numbers is listed in Table 8-1. The suffix can be
dropped for clarity when the context makes the intended radix obvious. The suffix
convention requires letters within hexadecimal numbers to be capitalized
[ABCDEF].
Table 8-1. Number Representation
8-2
Type
Suffix
Binary
b
01b, 1010b
Decimal
d
01d, 999d
Octal
o
01o, 174o
Hexadecimal
h
01h, 08E002FCh
Conexant
Example
100660E
CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.3 Bit Stream Transmission Convention
8.3 Bit Stream Transmission Convention
Digitized voice transmission represented by octets (8-bit fields) generally
numbers bits left to right, 0–7, respectively. Data is transmitted serially starting at
the most significant bit (left-most bit, numbered bit 0) and proceeding to the
right-most bit (least significant bit, numbered bit 8) of the sample. The receiver
receives the most significant bit first. Table 8-2 illustrates this sequence.
Table 8-2. Digitized Voice Transmission Convention
Bit
0 (MSB)
1
2
3
4
5
6
7 (LSB)
Data
1
0
1
0
1
1
1
1
Transmission Order
Bit Stream = 10101111......
MSB is transmitted first
Digital data transmission uses n-bit words and generally numbers bits right to
left, 0 to [n-1], respectively. Data is transmitted serially starting with the least
significant bit (right-most bit or bit 0) and proceeding to the most significant bit
(left-most bit or bit [n – 1]). The receiver receives the least significant bit first.
Table 8-3 illustrates this sequence.
Table 8-3. Digital Data Transmission Convention
Bit
7 (MSB)
6
5
4
3
2
1
0 (LSB)
Data
1
0
1
0
1
1
1
1
Transmission Order
Bit Stream = 11110101......
LSB is transmitted first
MUSYCC employs the digital data transmission convention. MUSYCC
extensively uses 32-bit wide dwords or double-words data transfers. The data is
transmitted and received as listed in Table 8-4.
Table 8-4. MUSYCC Byte Transmission Convention
Byte
Transmission and
Reception Order
100660E
3
MSB
Bits 7 <- 0
2
1
0
LSB
Bits 7 <- 0
Byte Stream = Byte 0, Byte 1, Byte 2, Byte 3......
Conexant
8-3
CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.4 Bit Stream Storage Convention
8.4 Bit Stream Storage Convention
MUSYCC stores and retrieves bit stream data to and from memory using little
endian-style byte ordering, which causes the least significant byte to be stored in
and retrieved from the lowest memory address.
Tables 8-5 and 8-6 list little and big endian byte ordering within a dword using
the 32-bit dword 7654321h.
Table 8-5. Little-Endian Storage Convention (Intel-style)
Address
x
x+1
Data
x+2
x+3
10h
32h
54h
76h
32h
10h
Table 8-6. Big-Endian Storage Convention (Motorola-style)
Address
x
8-4
x+1
Data
x+2
x+3
76h
Conexant
54h
100660E
CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.5 Acronyms
8.5 Acronyms
ABT
ALIGN
BLP
BPS (bps)
BUFF
CHABT
CHIC
Alignment error
Bit Level Processor
Bits Per Second
Buffer error
Change to Abort Code
Change to Idle Code
CMOS
Complementary Metal Oxide Semiconductor
COFA
Change of Frame Alignment
CRC
Cyclic Redundancy Check
DMA
Direct Memory Access
DMAC
DMI
dword
DXI
Direct Memory Access Controller
Digital Multiplexed Interface
Double Word
Data Exchange Interface
EBUS
Expansion Bus
EOB
End of Buffer
EOM
End of Message
EOP
End of Pad Fill
FCS
Frame Check Sequence
FIFO
First In First Out
FRAD
Frame Relay Access Devices
FREC
Frame Recovery
HDLC
High-Level Data Link Control
IC
Idle Code
INTC
Interrupt Controller
IRAM
Internal RAM
ISDN
100660E
Abort Termination error
Integrated Service Digital Network
Conexant
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8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.5 Acronyms
ISLP
ISO
JTAG
International Standard for Organization
Joint Test Action Group
kbps
Kilobits per Second
LNG
Long Message Error
LSB
Least Significant Bit or Byte
MB
Megabyte
MBPS (Mbps)
MSB
MUSYCC
Megabits Per Second
Most Significant Bit or Byte
Multichannel Synchronous Communication Controller
ONR
Host Ownership of Buffer
OOF
Out of Frame
OSI
Open System Interconnection
PCI
Peripheral Component Interface
PCM
Pulse Code Modulated
PQFP
Plastic Quad Flat Pack
ROOF
Receiver Out of Frame
RX (Rx)
SDEC
Receive/Receiver
SUERM Octet Count Decrement
SERI
Serial Port Interfaces
SFILT
SS7 Filtered Message
SHT
SINC
SS7
Short Message error
SUERM Octet Count Increment
Signaling System 7
SUERM
Signal Unit Error Rate Monitor
SUERR
Signal Unit Error Rate Interrupt
SUET
TS
TX (Tx)
8-6
Inter-System Link Protocol
Signal Unit Error Threshold
Time Slot
Transmit/Transmitter
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.6 Definitions
8.6 Definitions
bit field
byte
A field made up of 8 binary bits.
channel
A logical bit stream through MUSYCC. A channel has an associated transmit and
receive direction. The transmit direction is for the bit stream flowing from shared
memory towards the serial port. The receive direction is for the bit stream flowing
from the serial port to the shared memory. A channel within MUSYCC is
bidirectional. The rate of data flow is configurable and is specified in bits per
second.
channelized
A serial port configuration whereby a higher speed bit stream is partitioned into
lower speed bit streams or time slots. A frame synchronization signal is required
and allows mapping of individual bits within the time slots into logical channels.
This term is synonymous with PCM Highway.
channel group
data buffer
descriptor
dword
FIFO
flag
100660E
Any group of associated information bits that must always be viewed together to
provide the desired information. For example, in a 3-bit field, the 3 bits can
represent 8 related values and thus must always be viewed together.
MUSYCC is designed around four independent and full-duplexed sets of
channels. Each channel group supports up to 32 logical channels.
A block of shared memory where data messages are stored. As messages are
received from the serial port, MUSYCC writes the message to shared memory
data buffers. As messages are sent out on the serial port, MUSYCC takes
messages from shared memory data buffers.
A data structure used to specify attributes of a separate block of data.
A field consisting of 32 binary bits, or 2 words concatenated, or 4 bytes
concatenated.
A region of memory designed to facilitate the movement of bits of information in
a first-in-first-out manner.
As defined by HDLC protocol, an octet with the value 7Eh (01111110b).
frame
In the context of an HDLC bit stream, this term is synonymous with message and
packet. In terms of a serial interface, a frame is a grouping of synchronous bits
relative to a serial line clock and delimited by a synchronization signal. The frame
structure is defined by the physical interface providing the framed data.
hyperchannel
Concatenation of time slots into a single logical channel. The available bandwidth
for such a logical channel is the sum of bandwidth of each time slot.
idle code
An octet pattern used to fill the time between the closing flag of one message and the
opening flag of the subsequent message. The following idles codes are supported:
7Eh, FFh, and 00h.
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.6 Definitions
message
octet
pointer
subchannel
time slot
word
8-8
In the context of an HDLC protocol, a data message consists of a header field, an
address field, a control field, a payload field, and an FCS field delimited by an
opening and a closing flag—7Eh (01111110h). This term is synonymous with
frame and packet.
A field made up of 8 binary bits. Synonymous with byte.
A 32-bit field containing the address of another bit field, descriptor, dword, word,
or byte.
When a 64 kbps time slot (or channel) consists of lower rate bit streams (in
multiples of 8 kbps), each bit stream is said to be a subchannel of the original
channel.
An 8-bit portion of a channelized T1 or E1 frame which repeats every 125 µs and
represents a 64 kbps signal. In channelized T1 and E1 frames, 24 and 32 time
slots operate at 64 kbps.
A field made up of 16 binary bits or 2 bytes concatenated.
Conexant
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CN8478/CN8474A/CN8472A/CN8471A
8.0 Terms, Definitions, and Conventions
Multichannel Synchronous Communications Controller (MUSYCC™)
8.7 Revision History
8.7 Revision History
Table 8-7. CN8478 Data Sheet Revisions
Revision
Date
Change
Rev. A
01/25/99
—
Rev. B
—
03/12/99
Corrected grammar. Added BGA mechanical diagram and package thermal
specification.
Rev. C
—
07/29/99
Added BGA pinout, further defined pinout description, replaced BGA
mechanical diagram, and updated package thermal specification.
Rev. D
—
3/27/00
100660E
Description
Initial Release.
–Added 66 MHz PCI clock rate information.
–Removed Protected Memory function (Section 5.2.2.4).
–Removed POLLTH = 0 option.
–Added Section 6.2.6.1. and Section 6.2.6.2.
–Removed PCI Bus Utilization function (previously Section 4.7.2).
–Added details on interrupt processing at the end of Section 5.2.5.2.
–Changed MCENBL to 1 in Section 6.3.5.
–Changed TRST* to pulled low in normal operation.
Conexant
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8.0 Terms, Definitions, and Conventions
8.7 Revision History
8-10
Multichannel Synchronous Communications Controller (MUSYCC™)
Conexant
100660E
A
Appendix A JTAG Interface
The CN8478 supports boundary scan testing conforming to IEEE standard
1149.1a-1993 and supplement 1149.1b. 1994. This appendix is intended to assist
the customer in developing boundary scan tests for printed circuit boards and
systems that use the CN8478. It is assumed that the reader is familiar with
boundary scan terminology. For the latest version of the Boundary Scan
Description Language (BSDL) file, contact Technical Publications.
The JTAG Interface section of the CN8478 provides access to all external I/O
signals of the device for board and system level testing. This circuitry also
conforms to IEEE std 1149.1a-1993.
A.1 Instruction Register
The Instruction register (IR) is a 3-bit register. When the boundary scan circuitry
is reset, the IR is loaded with the BYPASS Instruction. The Capture-IR binary
value is 001.
The eight instructions include three IEEE 1149.1 mandatory public
instructions (BYPASS, EXTEST, and SAMPLE/PRELOAD) and five private
instructions for manufacturing use only. Bit 0 (LSB) is shifted into instruction
register first.
Table A-1. IEEE Std. 1149.1 Instructions
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Bit 2
Bit 1
Bit 0
Instruction
Register Accessed
0
0
0
EXTEST
Boundary Scan
0
0
1
SAMPLE/PRELOAD
Boundary Scan
0
1
0
Private
—
0
1
1
Private
—
1
0
0
Private
—
1
0
1
Private
—
1
1
0
Private
—
1
1
1
BYPASS
Bypass
Conexant
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Appendix A JTAG Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
A.2 BYPASS Register
A.2 BYPASS Register
The BYPASS register is a 1-bit shift register that passes TDI data to TDO, which
facilitates testing other devices in the scan path without having to shift the data
patterns through the compare Boundary Scan register of the CN8478.
Table A-2. JTAG Timing Table
Label
A-2
Description
Min
Max
Unit
—
100
ns
tper
Period, TCK
tpwl
Pulse Width Low, TCK
0.4 tper
0.6 tper
ns
tpwh
Pulse Width High, TCK
0.4 tper
0.6 tper
ns
trec
Recovery, the rising edge of TCK from the rising edge of TRST~
100
—
ns
ts
Setup, TMS, TDI to the rising edge of TCK
15
—
ns
th
Hold, TMS, TDI from the rising edge of TCK
15
—
ns
ten
Enable, TDO from the falling edge of TCK
—
15
ns
tpd
Propagation Delay, TDO from the falling edge of TCK
—
15
ns
tdis1
Disable, TDO from the falling edge of TCK
—
15
ns
tdis2
Disable, TDO from the falling edge of TRST~
—
100
ns
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CN8478/CN8474A/CN8472A/CN8471A
Appendix A JTAG Interface
Multichannel Synchronous Communications Controller (MUSYCC™)
A.2 BYPASS Register
Figure A-1. JTAG Timing Diagram
trec
TRST~
ts
th
ts
th
TMS
TDI
tpwh
tpwl
tper
TCK
tpd
ten
tdis1
tdis2
TDO
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Appendix A JTAG Interface
A.2 BYPASS Register
A-4
Multichannel Synchronous Communications Controller (MUSYCC™)
Conexant
100660E
0.0 Sales Offices
Further Information
[email protected]
(800) 854-8099 (North America)
(949) 483-6996 (International)
Printed in USA
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92660-3007
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