CS89712
High-Performance, Low-Power System-on-Chip with 10BASE-T Ethernet Controller
Features
Description
l ARM720T (ARM7 TDMI) processor
The low-power high-performance CS89712 is designed
for ultra-low-power communication applications such as
VoIP telephones, industrial control, data acquisition,
special purpose servers and RF to Ethernet bridges. The
core-logic functionality of the device is built around an
ARM720T processor with 8 Kbytes of four-way set-associative unified cache and a write buffer. Incorporated into
the ARM720T is an enhanced memory management unit
(MMU) which allows for support of sophisticated operating systems like embedded Linux.
– 8 Kbytes of four-way set-associative cache
– MMU with 64-entry TLB
– Write Buffer
– Thumb code support enabled
l Dynamically clocked at 18, 36, 49 or 74 MHz
l 10 Mbit Ethernet Controller with integrated PHY
l Comprehensive Suite of Software Drivers
l On-Chip Transmit and Receive RAM Buffers
l 10BASE-T Port with Analog Filters provides
automatic polarity detection and correction
l Programmable Transmit Features:
– Automatic Re-transmission on Collision
– Automatic Padding and CRC Generation
l Programmable Receive Features:
– Early Interrupts for Frame Pre-Processing
– Automatic Rejection of Erroneous Packets
The CS89712 Ethernet port includes on-chip RAM and
10BASE-T transmit and receive filters.
ORDERING INFO
CS89712-CB
0 to 70° C
256 Ball PBGA 17x17 mm
10BASE-T
ETHERNET
3.6864 MHZ
PLL
INTERNAL DATA BUS
D[0-31]
ARM720T
32.768 KHZ
NPOR, RUN,
RESET, WAKEUP
32.768-KHZ
OSCILLATOR
POWER
MANAGEMENT
EINT[1-2], FIQ,
MEDCHG
INTERRUPT
CONTROLLER
SSI (ADC)
INTERFACE
CL-PS6700
INTFCE.
STATE CNTRL
BATOK, EXPWR
PWRFL, BATCHG
FLASHING LED DRIVE
PORTS A, B, D (8-BIT)
PORT E (3-BIT)
KEYBD DRIVERS (0–7)
BUZZER DRIVE
DC-TO-DC
MEMORY CONTROLLER
ARM7TD
8-KBYTE
CACHE
EXPANSION
CONTROL
MMU
RTC
SDRAM CNTRL
WRITE
BUFFER
INTERNAL ADDRESS BUS
LCD
ICE-JTAG
GPIO
TIMER
LCD
CONTROLLER
PWM
ON-CHIP
BOOT ROM
SSI1 (ADC)
ON-CHIP SRAM
48K BYTES
DAI
EPB
SSI2
DAI / SSI / ADC
INTERFACE
CODE
Preliminary Product Information
P.O. Box 17847, Austin, Texas 78760
(512) 445 7222 FAX: (512) 445 7581
http://www.cirrus.com
PB[0:1], NCS[4:5]
EXPCLK, WORD,
NCS[0:3], EXPRDY,
WRITE
MOE, MWE, SDCLK,
SDQM[0:1], SDRAS,
SDCAS
A[0-27],
DRA[0-14]
TEST AND
DEVELOPMENT
LCD DRIVE
IrDA
LED AND
PHOTODIODE
UART
ASYNC
INTERFACE 1
UART
ASYNC
INTERFACE
EPB BUS
2
This document contains information for a new product.
Cirrus Logic reserves the right to modify this product without notice.
Copyright Cirrus Logic, Inc. 2001
(All Rights Reserved)
FEB ‘01
DS502PP2
1
CS89712
Table Of Contents
1. OVERVIEW ............................................................................................................................... 4
2. FUNCTIONAL DESCRIPTION ................................................................................................. 7
2.1 CPU Core ............................................................................................................................ 7
2.2 State Control ....................................................................................................................... 7
2.3 Power-Up Sequence ......................................................................................................... 10
2.4 Resets ............................................................................................................................... 10
2.5 Ethernet Port Reset and Initialization ................................................................................ 11
2.6 Ethernet EEPROM Configurations .................................................................................... 12
2.7 Clocks ............................................................................................................................... 16
2.8 Interrupt Controller ............................................................................................................ 17
2.9 Boot ROM ......................................................................................................................... 21
2.10 Memory Map ................................................................................................................... 21
2.11 Memory and I/O Expansion Interface .............................................................................. 23
2.12 SDRAM Controller ........................................................................................................... 23
2.13 SDRAM Initialization ....................................................................................................... 26
2.14 CL-PS6700 PC Card Interface ........................................................................................ 26
2.15 Endianness ..................................................................................................................... 29
2.16 Internal UARTs and SIR Encoder ................................................................................... 30
2.17 Synchronous Serial Interfaces ........................................................................................ 31
2.18 LCD Controller ................................................................................................................ 39
2.19 Timer Counters ............................................................................................................... 41
2.20 Real-Time Clock .............................................................................................................. 43
2.21 Dedicated LED Flasher ................................................................................................... 43
2.22 PWM Interfaces ............................................................................................................... 43
2.23 Ethernet Port Architecture ............................................................................................... 44
2.24 Ethernet Port Functional Description .............................................................................. 45
2.25 Programming the EEPROM ............................................................................................ 46
2.26 Ethernet LEDs ................................................................................................................. 48
2.27 Media Access Control Engine ......................................................................................... 48
2.28 Encoder/Decoder (ENDEC) ............................................................................................ 53
2.29 10BASE-T Transceiver ................................................................................................... 54
2.30 Basic Transmit Operation ................................................................................................ 56
2.31 Basic Receive Operation ................................................................................................. 56
2.32 Managing Interrupts & Status Queue .............................................................................. 57
2.33 Basic Receive Operation ................................................................................................. 57
2.34 Receive Frame Address Filtering .................................................................................... 63
2.35 Transmit Operation ......................................................................................................... 66
2.36 Full Duplex Considerations ............................................................................................. 69
2.37 Auto-Negotiation Considerations .................................................................................... 69
Contacting Cirrus Logic Support
For a complete listing of Direct Sales, Distributor, and Sales Representative contacts, visit the Cirrus Logic web site at:
http://www.cirrus.com/corporate/contacts/sales.cfm
Preliminary product information describes products which are in production, but for which full characterization data is not yet available. Advance product information describes products which are in development and subject to development changes. Cirrus Logic, Inc. has made best efforts to ensure that the information
contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided “AS IS” without warranty of
any kind (express or implied). No responsibility is assumed by Cirrus Logic, Inc. for the use of this information, nor for infringements of patents or other rights
of third parties. This document is the property of Cirrus Logic, Inc. and implies no license under patents, copyrights, trademarks, or trade secrets. No part of
this publication may be copied, reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photographic, or
otherwise) without the prior written consent of Cirrus Logic, Inc. Items from any Cirrus Logic website or disk may be printed for use by the user. However, no
part of the printout or electronic files may be copied, reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical,
photographic, or otherwise) without the prior written consent of Cirrus Logic, Inc.Furthermore, no part of this publication may be used as a basis for manufacture
or sale of any items without the prior written consent of Cirrus Logic, Inc. The names of products of Cirrus Logic, Inc. or other vendors and suppliers appearing
in this document may be trademarks or service marks of their respective owners which may be registered in some jurisdictions. A list of Cirrus Logic, Inc. trademarks and service marks can be found at http://www.cirrus.com.
2
DS502PP2
CS89712
3. REGISTER SET ...................................................................................................................... 70
3.1 Internal Registers .............................................................................................................. 70
3.2 Accessing Ethernet Port Registers ................................................................................... 73
3.3 Ethernet Port Internal Memory Map .................................................................................. 77
3.4 I/O Port Data Registers ..................................................................................................... 78
3.5 System Control Registers ................................................................................................. 79
3.6 Interrupt Registers ............................................................................................................ 89
3.7 Expansion Memory Configuration Registers ..................................................................... 92
3.8 Timer / Counter Registers ................................................................................................. 95
3.9 Miscellaneous Registers ................................................................................................... 95
3.10 UART Registers .............................................................................................................. 98
3.11 LCD Registers ............................................................................................................... 100
3.12 SSI Register .................................................................................................................. 103
3.13 End Of Interrupt Locations ............................................................................................ 104
3.14 State Control Registers ................................................................................................. 105
3.15 SS2 Registers ............................................................................................................... 106
3.16 DAI Registers ................................................................................................................ 106
3.17 Ethernet Bus Interface Registers .................................................................................. 117
3.18 Ethernet Port Status/Control Registers ......................................................................... 117
4. TEST & DEBUG MODES ..................................................................................................... 137
4.1 Entering test modes ........................................................................................................ 137
4.2 Boundary Scan ............................................................................................................... 139
4.3 In-Circuit Emulation ......................................................................................................... 140
5. MECHANICAL INFORMATION ............................................................................................ 142
5.1 256-PBGA Pin Diagram .................................................................................................. 142
5.2 256-Ball PBGA Ball Listing ............................................................................................. 143
5.3 External Signal Functions
.......................................................................................... 147
5.4 Output Bi-Directional Pins ............................................................................................... 151
5.5 256 PBGA Package Dimensions .................................................................................... 153
6. ELECTRICAL/THERMAL INFO ........................................................................................... 154
6.1 Absolute Maximum Ratings ............................................................................................ 154
6.2 DC Characteristics .......................................................................................................... 154
6.3 AC Characteristics .......................................................................................................... 157
6.4 I/O Buffer Strength & Characteristics .............................................................................. 169
7. ORDERING INFORMATION ................................................................................................ 170
DS502PP2
3
CS89712
1. Overview
CRYSTAL
MOSCIN
CRYSTAL
RTCIN
DD[3:0]
CL1
CL2
FM
M
CS[4]
PB0
EXPCLK
LCD MODULE
COL[7:0]
KEYBOARD
PA[7:0]
CL-PS6700
PC CARD
CONTROLLER
PC CARD
SOCKET
PB[7:0]
PD[7:0]
PE[2:0]
SDRAM
A[27:0]
SDQM[3:0]
SDCS0
SDCS1
SDCAS
SDRAS
CS89712
D[31:0]
POR
PWRFL
BATOK
EXTPWR
BATCHG
RUN
WAKEUP
DRIVE[1:0]
SDRAM
FB[1:0]
NCS[0]
NCS[1]
× 16
FLASH
× 16
FLASH
× 16
FLASH
× 16
FLASH
BUFFERS
CS[2]
CS[3]
ADDITIONAL I/O
BUFFERS
AND
LATCHES
ETHERNET
CRYSTAL
DC
INPUT
BATTERY
DC-TO-DC
CONVERTERS
SSICLK
SSITXFR
SSITXDA
SSIRXDA
CODEC/SSI2/
DAI
LEDDRV
PHDIN
IR LED AND
PHOTODIODE
MOE
WRITE
CS[n]
WORD
EXTERNAL MEMORYMAPPED EXPANSION
POWER
SUPPLY UNIT
AND
COMPARATORS
EXTL1
EXTL2
RxD1/2
TxD1/2
DSR
CTS
DCD
ADCCLK
ADCCS
ADCOUT
ADCIN
SMPCLK
RXDRXD+
TXDTXD+
2× RS-232
TRANSCEIVERS
ADC
DIGITIZER
ETHERNET
TRANSFORMER
Figure 1. A CS89712–Based System
4
DS502PP2
CS89712
The CS89712 contains a single-chip embedded
controller designed to be used in low-cost and ultra-low-power applications. Operating at 74 MHz,
the CS89712 delivers about 66 Dhrystone
2.1 MIPS sustained (74 MIPS peak).
-
10BASE-T transceiver including drivers,
receivers, and analog filters, for direct connection to low-cost isolation transformers.
The CS89712 contains the following features:
-
very low noise emission, shortening EMI
testing and qualification time.
•
ARM720T processor with:
-
•
It provides on-chip LED drivers for link status, bus status, and Ethernet line activity.
ARM7TDMI CPU core (supporting the
Thumb instruction set and with enhanced
multiplier) running at a dynamic clock
speeds of 18, 36, 49, or 74 MHz
-
Advanced power management
-
Memory Management Unit compatible
with the ARM710 core (and a 64-entry
translation lookaside buffer) with added
support for Windows CE
-
8 kbytes of unified instruction/data cache
with a four-way set associative controller
-
Write buffer
-
JTAG, core debug and full embedded ICE
•
48k bytes of on-chip SRAM sharable between
the LCD controller and general applications
•
Low power operation. Typical power dissipated is 270 mW at 74 MHz in the Operating State
and 160 mW in the Idle State (clock to the CPU
stopped, everything else running), with
<150 uW in the Standby State (realtime clock
‘on’, everything else stopped). The Ethernet
block has a Software Suspend state, disabling
the receiver and dropping current to the microampere range.
•
Advanced audio decoder / decompression supports multiple audio decompression algorithms
at all standard sample & bit rates. MPEG 1, 2,
and 2.5 layer 3 audio decoding is supported, including ISO compliant MPEG 1 and 2 layer 3
support. Adaptive bit rates are supported.
•
Up to 64 MHz of SDRAM can operate at up to
36.864 MHz with 16- or 32-bit wide accesses.
•
ROM / SRAM / FLASH Memory controller decodes up to 5 separate memory segments each
up to 256 Mbytes. Each segment can be configured as 8, 16, or 32 bits wide with page-mode
access support and programmable access times.
Supports removable FLASH card interface for
addition of expansion FLASH modules.
•
27 general-purpose I/O bits; three 8-bit and one
3-bit port support scanning keyboard matrix.
•
Digital Audio Interface (DAI) for interfacing to
CD-quality DACs and CODECs.
•
Interrupt controller.
•
IrDA 115.2 kbps SIR protocol controller.
Full 10BaseT Ethernet port, with all the analog
& digital circuitry needed for a complete Ethernet circuit, having:
-
-
-
Media Access Control (MAC) IEEE 802.3
compliant full-duplex engine. It handles all
aspects of Ethernet frame transmission and
reception, including: collision detection,
preamble generation and detection, and
CRC generation and test. Features include
automatic retransmission on collision, and
automatic padding of transmitted frames.
4 kbyte page of on-chip memory, eliminating external memory chips.
serial EEPROM interface allowing configuration information storage for automatic
load at power-up.
A Manchester encoder/decoder, clock recovery circuit, and 10BASE-T transceiver.
DS502PP2
5
CS89712
•
•
LCD controller interfaces directly to a singlescan panel monochrome LCD. Panel width size
is programmable from 32 to 1024 pixels in 16pixel increments. Video frame buffer size programmable up to 128 kbytes with 1, 2, or 4 bits
per pixel supports 15-level grayscale operation.
Programmable frame buffer address allows a
system with only internal SRAM for memory.
•
On-chip boot ROM programmed with serial
load boot sequence.
•
Two 16-bit general purpose timer counters.
•
32-bit Real-Time Clock and comparator.
•
Dedicated LED flasher pin driven from the
RTC with programmable duty ratio (multiplexed with a GPIO pin).
•
Two 16550 type UARTs:
-
support bit rates up to 115.2 kbps
-
contain two 16-byte FIFOs for TX and RX
-
UART1 supports modem control signals
•
Two synchronous serial interfaces for Microwire (128 kbps) or SPI peripherals such as
ADCs, one supporting both master/slave mode
and the other supporting master mode only.
•
PWM interface provides two 96 kHz clocks
with programmable 1/16 to 15/16 duty cycle
for driving a DC to DC converter.
6
•
An interface to one or two Cirrus Logic CLPS6700 PC Card controller devices to support
two PC Card slots.
•
Oscillator and phase-locked loop (PLL) to generate the core clock speeds of 18.432 MHz,
36.864 MHz, 49.152 MHz, and 73.728 MHz
from an external 3.6864 MHz crystal.
•
A low-power 32.768 kHz oscillator.
•
Suite of software drivers for immediate use
with most industry standard network operating
systems. In addition, complete evaluation kits
and manufacturing packages significantly reduce production cost and time.
•
Commercial 0 - 70C operating temperature.
The CS89712 design is optimized for low power
dissipation and is fabricated on a fully static
0.25 micron CMOS process. It is available in a
256-ball PBGA package.
A maximum configured system using the CS89712
is shown in Figure 1. This system assumes all of the
DRAMs and ROMs are 16-bit wide devices. The
keyboard may be connected to more GPIO bits than
shown to allow greater than 64 keys, however these
extra pins will not be wired into the WAKEUP pin
functionality. Note that only one of the CODEC,
SSI2, or DAI interfaces may be used at a time.
DS502PP2
CS89712
2. FUNCTIONAL DESCRIPTION
2.1 CPU Core
The ARM720T consists of an ARM7TDMI 32-bit
RISC processor, a unified 8 kbyte cache, and a
memory management unit (MMU). The cache is
four-way set associative organized as 512 lines
with each line being 16 bytes. The cache is directly
connected to the ARM7TDMI, and therefore caches the virtual address from the CPU. When the
cache misses, the MMU translates the virtual address into a physical address. A 64-entry translation
lookaside buffer (TLB) is utilized to speed the address translation process and reduce bus traffic necessary to read the page table. The MMU saves
power by only translating cache misses.
See the ARM720T Data sheet for a complete description of the various logic blocks that make up
the processor, as well as all internal registers.
2.2 State Control
The CS89712 supports the following Power Management States: Operating, Idle, and Standby (see
Figure 2). There is also a state called the Doze
State, however it is a temporary execution state.
The normal program execution state is the Operating State, which is a full performance state where
all of the clocks and peripheral logic are enabled.
The Idle State is the same as the Operating State
with the exception of the CPU clock being halted,
and only an external interrupt will return it back to
the Operating State. The Standby State has the lowest power consumption of the three states. By selecting this mode the main oscillator shuts down,
leaving only the Real-Time Clock and its associated logic powered. When the CS89712 is in Standby
all power and ground pins should remain connected
to power and ground in order to have a proper system wake-up. The only state that Standby can transition to is the Operating State.
2.2.1
Standby State
The Standby State equates to the system being
switched "off" (i.e., no display, and the main oscillator is shut down). The PLL will be shut down.
In the Standby State, all the system memory and
state is maintained and the system time is kept upto-date. The PLL/on-chip oscillator or external oscillator is disabled and the system is static, except
for the low-power watch crystal (32 kHz) oscillator
and divider chain to the RTC and LED flasher. The
RUN signal is driven low, therefore this signal can
be used externally in the system to power down
other system modules.
Whenever the CS89712 is in the Standby State, the
external address and data buses are forced low internally by the RUN signal. This is done to prevent
peripherals that are powered down from draining
Interrupt or rising wakeup
Standby
Operating
Write to standby location,
power fail, or user reset
I
nPOR, power fail,
or user reset
pt
ru
er
t
n
Write to halt location
Idle
Figure 2. State Diagram
DS502PP2
7
CS89712
Address (W/B)
Operating
Idle
Standby
nPOR
RESET
nURESET
RESET
SDRAM Control
On
On
SELFREF
Off
N/A
UARTs
On
On
Off
Reset
Reset
LCD FIFO
On
On
Reset
Reset
Reset
LCD
On
On
Off
Reset
Reset
ADC Interface
On
On
Off
Reset
Reset
SSI2 Interface
On
On
Off
Reset
Reset
DAI Interface
On
On
Off
Reset
Reset
CODEC
On
On
Off
Reset
Reset
Timers
On
On
Off
Reset
Reset
RTC
On
On
On
On
On
LED Flasher
On
On
On
Reset
Reset
DC-to-DC
On
On
Off
Reset
Reset
CPU
On
Off
Off
Reset
Reset
Interrupt Control
On
On
On
Reset
Reset
PLL/CLKEN Signal
On
On
Off
Off
Off
Table 1. Peripheral Status in Different Power Management States
current. Also, the internal peripheral’s signals get
set to their Reset State.
When first powered, or reset by the nPOR (Power
On Reset, active low) signal, the CS89712 is forced
into the Standby State. This is known as a cold reset, and when leaving the Standby State after a cold
reset, external wake up is the only way to wake up
the device. When leaving the Standby State after
non-cold reset conditions (i.e., the software has
forced the device into the Standby State), the transition to the Operating State can be caused by a rising edge on the WAKEUP input signal or by an
enabled interrupt. Normally, when entering the
Standby State from the Operating State, the software will leave some interrupt sources enabled.
Note:
The CPU cannot be awakened by the TINT,
WEINT, and BLINT interrupts when in the
Standby State.
Typically, software writes to the Standby internal
memory location to cause the transition from the
Operating State to the Standby State. Before enter8
ing the Standby State, if external I/O devices (such
as the CL-PS6700s connected to nCS[4] or nCS[5])
are in use, the software must ensure that they are
idle before writing to the Standby State location.
Before entering the Standby State, the software
must properly disable the DAI. Failing to do so will
result in higher than expected power consumption
in the Standby State, as well as unpredictable operation of the DAI. The DAI can be re-enabled after
transitioning back to the Operating State.
The system can also be forced into the Standby
State by hardware if the nPWRFL or nURESET inputs are forced low. The only exit from the Standby
State is to the Operating State.
The system will only transition to the Operating
State from the Standby State under the following
conditions: when the nPWRFL input pin is high,
when the nEXTPWR input pin is low, or when the
BATOK input pin is high. This prevents the system
from starting when the power supply is inadequate
DS502PP2
CS89712
(i.e., the main batteries are low), corresponding to
a low level on nPWRFL or BATOK.
From the Standby State, if the WAKEUP signal is
applied with no clock except the 32 kHz clock running, the CS89712 will be initialized into a state
where it is ready to start and is waiting for the CPU
to start receiving its clock. The CPU will still be
held in reset at this point. After the first clock is applied, there will be a delay of about eight clock cycles before the CPU is enabled. This delay allows
the CPU clock to settle.
2.2.1.1
UART in Standby State
During the Standby State, the UARTs are disabled
and cannot detect any activity (i.e., start bit) on the
receiver. If this functionality is required then this
can be accomplished in software by the following
method:
1) Permanently connect the RX pin to one of the
active low external interrupt pins.
Operating State and execute the next instruction.
The WAKEUP signal can not be used to exit the
Idle State. It is only used to exit the Standby State.
In the Idle State, the device functions just like it
does when in the Operating State. However, the
CPU clock is halted while it waits for an event such
as a key press to generate an interrupt. The PLL always remains active in the Idle State.
2.2.3
For the case of the keyboard interrupt, the following options are available and are selectable according to bits 1 and 3 of the SYSCON2 register (refer
to Section 3.5.2 for register details).
•
If the KBWEN bit (SYSCON2 bit 3) is set low,
then a keypress will cause a transition from a
power saving state only if the keyboard interrupt is non-masked (i.e., the interrupt mask register 2 (INTMR2 bit 0) is high).
•
When KBWEN is high, a keypress will cause
the device to wake up regardless of the state of
the interrupt mask register. This is called the
“Keyboard Direct Wakeup’ mode. In this
mode, the interrupt request may not get serviced. If the interrupt is masked (i.e., the interrupt mask register 2 (INTMR2 bit 0) is low),
the processor simply starts re-executing code
from where it left off before it entered the power saving state. If the interrupt is non-masked,
then the processor will service the interrupt.
•
When the KBD6 bit (SYSCON2 bit 1) is low,
all 8 Port A inputs are OR’ed together to produce the internal wakeup signal and keyboard
interrupt request. This is the default reset state.
•
When the KBD6 bit (SYSCON2 bit 1) is high,
only the lowest 6 bits of Port A are OR’ed together to produce the internal wakeup signal
and keyboard interrupt request. The two most
significant bits of Port A are available as GPIO
when this bit is set high.
2) Ensure that on entry to the Standby State, the
chosen interrupt source is not masked, and the
UART is enabled.
3) Send a preamble that consists of one start bit,
8 bits of zero, and one stop bit. This will cause
the CS89712 to wake and execute the enabled
interrupt vector.
The UART will automatically be re-enabled when
the processor re-enters the Operating State, and the
preamble will be received. Since the UART was
not awake at the start of the preamble, the timing of
the sample point will be off-center during the preamble byte. However, the next byte transmitted
will be correctly aligned. Thus, the actual first real
byte to be received by the UART will be correct.
2.2.2
Idle State
If in the Operating State, the Idle State can be entered by writing to a special internal memory location (HALT) in the CS89712. If an interrupt occurs,
the CS89712 will return immediately back to the
DS502PP2
Keyboard Interrupt Wakeup
9
CS89712
When both KBWEN and INTMR2 bit 0 are low,
the device can be awakened only by the external
WAKEUP pin or another enabled interrupt source.
The keyboard interrupt capability allows use of a
polled and/or interrupt-driven keyboard routine.
Notes:The keyboard interrupt is NOT deglitched.
2.2.4
Ethernet Port Software Suspend
The Ethernet port power features work in a different manner than detailed above. Suspend modemay be entered via software. During this mode, all
internal Ethernet circuits are shut off except the I/O
Base Address register (Ethernet Port offset address
0020h) and the SelfCTL register.
To enter Suspend mode, the SWSuspend bit (SelfCTL Register, bit 8) is set. To exit SW Suspend,
software must write to the CS89712 Ethernet (used
only to wake the Ethernet port, the Write data is ignored). Upon exit, the CS89712 Ethernet performs
a complete reset, and then goes through a normal
initialization procedure.
2.3 Power-Up Sequence
The following sequence should be followed to ensure proper start up. If any of the timing sequences
recommended below are violated, then the part
may not start up properly, requiring a hard reset to
recover.
1) Upon power, the signal nPOR must be held active (LOW) for a minimum of 100us, after VDD
has become settled.
2) After nPOR goes HIGH, the CS89712 will enter the Standby State (and only this state). In
this state, the PLL and CPU are not enabled.
The only method that can be used to allow the
CS89712 to exit the Standby State into the Operating State is by the WAKEUP signal going
active (HIGH).
Note:
10
It is not a requirement to use the nURESET
signal. If not used, the nURESET signal
must be HIGH, and it must have gone
HIGH prior to nPOR going HIGH. This is
due to the fact that nURESET is latched
into the device by the rising edge of nPOR.
When nURESET is LOW on the rising edge
of nPOR, it can force the device into one of
its Test Mode states.
3) After nPOR goes HIGH, the WAKEUP signal
cannot be detected as going HIGH, until after at
least two seconds. After two seconds, the
WAKEUP signal can become active, and it
must be HIGH for at least 125 us.
4) Before the WAKEUP signal is detected internally, it must go through a deglitching circuit.
This is why is must be active for at least 125us.
Then the PLL gets enabled. WAKEUP is ignored immediately after waking up the system.
It also ignores it while in the Idle or Operating
State. It can constantly toggle with no affect on
the device. It will only be read again if nPOR
goes low and then high again, or if software has
forced the device back into the Standby State.
5) A maximum of 250 msec will pass before the
CPU starts to fetch the first instruction.
2.4 Resets
There are three asynchronous resets to the
CS89712: nPOR (Power On Reset), nPWRFL, and
nURESET. If any of these are active, a system reset
is generated internally. This will reset all internal
registers in the CS89712 except the RTC data and
match registers. These registers are only cleared by
nPOR allowing the system time to be preserved
through a user reset or power fail condition.
NOTE: The Ethernet Port has different reset conditions
and considerations than described in this section. Refer to the following section for resetting
the Ethernet Port.
Any reset will also reset the CPU and cause it to
start execution at the reset vector when the
CS89712 returns to the Operating State.
Three signals are used to internally reset storage elements. These are nPOR, nSYSRES (System Reset) and nSTBY. nPOR is an external signal.
nSTBY is equivalent to the external RUN signal.
DS502PP2
CS89712
nPOR is the highest priority reset signal. When active (low), it will reset all storage elements in the
CS89712. nPOR active forces nSYSRES and nSTBY active. nPOR will only be active after the
CS89712 is first powered up and not during any
other resets. nPOR active clears all flags in the status register except for the cold reset flag (CLDFLG) bit (SYSFLG, bit 15), which is set.
2.5.1.1
nSYSRES is generated internally in the CS89712 if
either nPOR, nPWRFL, or nURESET are active. It
is the second highest priority reset signal, used to
asynchronously reset most internal registers.
nSYSRES activation forces nSTBY and RUN low,
and resets the CS89712 leaving it in the Standby
State.
There is a chip-wide reset whenever the RESET bit
(SelfCTL Register, Bit 6) is set.
The nSTBY and RUN signals are high when the
CS89712 is in the Operating or Idle States and low
when in the Standby State. The main system clock
is valid when nSTBY is high. The nSTBY signal
will disable any peripheral block that is clocked
from the master clock source (i.e., everything except for the RTC). However, when in Snooze State,
the LCD controller and the DC to DC converter interface peripherals will NOT be disabled.
2.5.2
In general, a system reset will clear all registers and
nSTBY will disable all peripherals that require a
main clock, with the exception of the Snooze State
operation as described above. The following peripherals are always disabled by a low level on
nSTBY: two UARTs and IrDA SIR encoder, timer
counters, telephony codec, and the two SSI interfaces. In addition, when in the Standby State, the
LCD controller and PWM drive are also disabled.
2.5 Ethernet Port Reset and Initialization
Different considerations apply to resetting and initializing the Ethernet Port.
2.5.1
Reset
Three different conditions cause the Ethernet port
to reset its Ethernet internal registers and circuits.
DS502PP2
Power-Up Reset
When power is applied, the Ethernet port maintains
reset until the voltage at the supply pins reaches approximately 2.5 V. The Ethernet port comes out of
reset once Vcc is greater than approximately 2.5 V
and the crystal oscillator has stabilized.
2.5.1.2
2.5.1.3
Software Initiated Reset
Software Suspend
Whenever the Ethernet port enters Software Suspend mode, all registers and circuits are reset.
Upon exit, there is a chip-wide reset.
Allowing Time for Reset Operation
After a reset, the Ethernet port goes through a self
configuration. This includes calibrating on-chip
analog circuitry, and reading EEPROM for validity
and configuration. Time required for the reset calibration is typically 10 ms. Software drivers should
not access registers internal to the CS89712 Ethernet during this time. When calibration is done, bit
INITD in the Self Status Register is set indicating
that initialization is complete, and the SIBUSY bit
in the same register is cleared indicating the EEPROM is no longer being read.
2.5.3
Initialization
After each reset (except EEPROM Reset), the
CS89712’s Ethernet port checks the sense of the
EEDataIn pin to see if an external EEPROM is
present. EEDI high indicates presence of an EEPROM and the Ethernet port automatically loads
the configuration data stored in the EEPROM into
its internal registers (see next section). If EEDI is
low, an EEPROM is not present and the Ethernet
port resets with the register values in Table 2.
An optional low-cost serial EEPROM can be used
to store configuration information that is automati-
11
CS89712
cally loaded into the Ethernet port after each reset
(except EEPROM reset).
The CS89712 Ethernet operates with any of six
standard EEPROMs shown in Table 3.
Ethernet Port
Address
Register
Contents
Register Descriptions
0020h
0300h
I/O Base Address
0022h
XXXX XXXX
XXXX X100
Interrupt Number
0102h
0003h
RxCFG Register
0104h
0005h
RxCTL Register
0106h
0007h
TxCFG Register
0108h
0009h
TxCMD Register
010Ah
000Bh
BufCFG Register
010Ch
Undefined
Reserved
010Eh
Undefined
Reserved
0110h
Undefined
Reserved
0112h
00013h
LineCTL Register
0114h
0015h
SelfCTL Register
0116h
0017h
BusCTL Register
0118h
0019h
TestCTL Register
EEPROM Interface
The EEPROM interface uses the signals shown in
Table 4.
Ethernet port
Pin
Ethernet port
Function
EEPROM
Pin
EECS
EEPROM Chip Select
Chip Select
EESK
1 MHz EEPROM
Serial Clock output
Clock
EEDO
EEPROM Data Out
(data to EEPROM)
Data In
EEDI
EEPROM Data in
(data from EEPROM)
2.6.2
Note: I/O base address is unaffected by Software
Suspend mode.
Size (16-bit words)
‘C46 (non-sequential)
64
‘CS46 (sequential)
64
‘C56 (non-sequential)
128
‘CS56 (sequential)
128
‘C66 (non-sequential)
256
‘CS66 (sequential)
256
Table 3. Supported EEPROM Types
12
2.6.1
Data Out
Table 4. EEPROM Interface
Table 2. Default Configuration
EEPROM Type
2.6 Ethernet EEPROM Configurations
EEPROM Memory Organization
If an EEPROM is used to store initial configuration
information for the Ethernet port, the EEPROM is
organized in one or more blocks of 16-bit words.
The first block in EEPROM, referred to as the Configuration Block, is used to configure the Ethernet
port after reset. An example of a typical Configuration Block is shown in Table 5. Additional blocks
containing user data may be stored in the EEPROM. However, the Configuration Block must
always start at address 00h and be stored in contiguous memory locations.
2.6.3
Reset Configuration Block
The first block in EEPROM, the Reset Configuration Block, is used to automatically program the
Ethernet port with an initial configuration after a
reset. Additional user data may also be stored in the
EEPROM if space is available. The additional data
are stored as 16-bit words and can occupy any EEPROM address space beginning immediately after
the end of the Reset Configuration Block up to address 7Fh, depending on EEPROM size. This additional data can only be accessed through software
control (refer to Section 2.24 for more information). Address space 80h to AFh is reserved.
DS502PP2
CS89712
Word Address
Value
Description
FIRST WORD in DATA BLOCK
00h
A120h
Configuration Block Header.
The high byte, A1h, indicates a ‘C46 EEPROM is attached. The Link
Byte, 20h, indicates the number of bytes to be used in this block of configuration data.
FIRST GROUP of WORDS
01h
2020h
Group Header for first group of words.
Three words to be loaded, beginning at 0020h in Ethernet Port memory.
02h
0300h
I/O Base Address
03h
0003h
Interrupt Number
04h
0001h
DMA Channel Number
SECOND GROUP of WORDS
05h
502Ch
Group Header for second group of words.
Six words to be loaded, beginning at 002Ch in Ethernet Port memory.
06h
E000h
Memory Base Address - low word
07
000Fh
Memory Base Address - high word
08h
0000h
Boot PROM Base Address - low word
09h
000Dh
Boot PROM Base Address - high word
0Ah
C000h
Boot PROM Address Mask - low word
0Bh
000Fh
Boot PROM Address Mask - high word
THIRD GROUP of WORDS
0Ch
2158h
Group Header for third group of words.
Three words to be loaded, beginning at 0158 in Ethernet Port memory.
0Dh
0010h
Individual Address - Octet 0 and 1
0Eh
0000h
Individual Address - Octet 2 and 3
0Fh
0000h
Individual Address - Octet 4 and 5
2800h
The high byte, 28h, is the Checksum Value. In this example, the checksum includes word addresses 00h through 0Fh. The hexadecimal sum of
the bytes is D8h, resulting in a 2’s complement of 28h. The low byte, 00h,
provides a pad to the word boundary.
CHECKSUM Value
10h
Note:
FFFFh is a special code indicating that there are no more words in the EEPROM.
Table 5. EEPROM Configuration Block Example
2.6.3.1
Reset Configuration Block Structure
The Reset Configuration Block is a block of contiguous 16-bit words starting at EEPROM address
00h. It can be divided into three logical sections: a
header, one or more groups of configuration data
DS502PP2
words, and a checksum value. All words in the Reset Configuration Block are read sequentially by
the Ethernet port after each reset, starting with the
header and ending with the checksum. Each group
of configuration data is used to program an Ether-
13
CS89712
net Port register (or set of Ethernet Port registers in
some cases) with an initial non-default value.
2.6.3.2
Reset Configuration Block Header
The header (first word of the block located at EEPROM address 00h) specifies the type of EEPROM used, if a Reset Configuration block is
present, and if so, how many bytes of configuration
data are stored in the Reset Configuration Block.
2.6.3.3
Determining the EEPROM Type
The LSB of the high byte of the header indicates
the type of EEPROM attached: sequential or nonsequential. An LSB of 0 (XXXX-XXX0) indicates
a sequential EEPROM, with a 1 (XXXX-XXX1)
indicating non-sequential EEPROM. The Ethernet
port functions with either type of EEPROM. The
Ethernet port will automatically generate sequential addresses while reading the Reset Configuration Block if a non-sequential EEPROM is used.
2.6.3.4
EEPROM Reset Configuration Block
The read-out of either a binary 101X-XXX0 or
101X-XXX1 from the high byte of the header indicates the presence of configuration data. Any other
readout value terminates initialization from the EEPROM. If an EEPROM is attached but not used for
configuration, the high byte of the first word should
be programmed with 00h in order to ensure that the
Ethernet port will not attempt to read configuration
data from the EEPROM.
2.6.3.5
Determining Number of Bytes in the
Reset Configuration Block
The low byte of the Reset Configuration Block
header is known as the link byte. The value of the
Link Byte represents the number of bytes of configuration data in the Reset Configuration Block. The
two bytes used for the header are excluded when
calculating the Link Byte value.
For example, a Reset Configuration Block header
of A104h indicates a non-sequential EEPROM pro-
14
grammed with a Reset Configuration Block containing 4 bytes of configuration data. This Reset
Configuration Block occupies 6 bytes (3 words) of
EEPROM space (2 bytes for the header and 4 bytes
of configuration data).
2.6.4
Groups of Configuration Data
Configuration data is arranged as groups of words.
Each group contains one or more words of data that
are to be loaded into Ethernet Port registers. The
first word of each group is referred to as the Group
Header. The Group Header indicates the number of
words in the group and the address of the Ethernet
Port register where the first data word in the group
is to be loaded. Any remaining words in the group
are stored in successive Ethernet Port registers.
2.6.4.1
Group Header
Bits F through C of the Group Header specify the
number of words in each group that are to be transferred to Ethernet Port registers (see Figure 3 for
the format). This value is two less than the total
number of words in the group, including the Group
Header. For example, if bits F through C contain
0001, there are three words in the group (a Group
Header and two words of configuration data).
Bits 8 through 0 of the Group Header specify a 9bit Ethernet Port Address. This address defines the
Ethernet Port register that will be loaded with the
first word of configuration data from the group.
Bits B though 9 of the Group Header are forced to
0, restricting the destination address range to the
first 512 bytes of Ethernet Port memory.
2.6.5
Reset Configuration Block Checksum
A checksum is stored in the high byte position of
the word immediately following the last group of
data in the Reset Configuration Block. (The EEPROM address of the checksum value can be determined by dividing the value stored in the Link Byte
by two.) The checksum value is the 2’s complement of the 8-bit sum (any carry out of eighth bit is
DS502PP2
CS89712
ignored) of all the bytes in the Reset Configuration
Block, excluding the checksum byte. This sum includes the Reset Configuration Block header at address 00h. Since the checksum is calculated as the
2’s complement of the sum of all preceding bytes in
the Reset Configuration Block, a total of 0 should
result when the checksum value is added to the sum
of the previous bytes.
2.6.7.1
2.6.6
The Ethernet port reads in the first word from the
EEPROM to determine if configuration data is contained in the EEPROM. If configuration data is not
stored in the EEPROM, the Ethernet port terminates initialization from EEPROM and operates using its default configuration (See Table 2). If
configuration data is stored in EEPROM, the Ethernet port automatically loads all configuration data
stored in the Reset Configuration Block into its internal Ethernet Port registers.
EEPROM Example
Table 5 shows an example of a Reset Configuration
Block stored in a C46 EEPROM. Note that littleendian word ordering is used, i.e., the least significant word of a multiword datum is located at the
lowest address.
2.6.7
EEPROM Read-out
If the EEDI pin is asserted high at the end of reset,
the Ethernet port reads the first word of EEPROM
data by:
1) Asserting EECS.
2) Clocking out a Read-Register-00h command
on EEDO (EESK provides a 1 MHz serial
clock signal).
3) Clocking the data in on EEDI.
If the EEDI pin is low at the end of the reset signal,
the Ethernet port does not perform an EEPROM
read-out (uses its default configuration).
Determining EEPROM Size
The Ethernet port determines the size of the EEPROM by checking the sense of EEDI on the tenth
rising edge of EESK. If EEDI is low, the EEPROM
is a ’C46 or ’CS46. If EEDI is high, the EEPROM
is a ’C56, ’CS56, ’C66, or ’CS66.
2.6.7.2
2.6.8
Loading Configuration Data
EEPROM Read-out Completion
Once all the configuration data are transferred to
the appropriate Ethernet Port registers, the Ethernet
port performs a checksum calculation to verify the
Reset Configuration Blocks data are valid. If the resulting total is 0, the read-out is considered valid.
Otherwise, the Ethernet port initiates a partial reset
to restore the default configuration.
If the read-out is valid, the EEPROMOK bit
(SelfST register, bit A) is set. EEPROMOK is
First Word of a Group of Words
F E D C B A 9 8 7 6 5 4 3 2 1 0
0
Number of Words
in Group
0
0
9-bit PacketPage Address
Figure 3. Group Header
DS502PP2
15
CS89712
cleared if a checksum error is detected. In this case,
the Ethernet port performs a partial reset and is restored to its default. Once initialization is complete
(configuration loaded from EEPROM or reset to
default configuration) the INITD bit (SelfST register, bit 7) is set .
2.7 Clocks
The clock source is the on-chip PLL, enabled by
strapping Port E pin 2 (PE[2]) low. This pin’s state
is latched at the rising edge of nPOR (power-up).
After power-up, PE[2] can be used as a GPIO.
The CS89712 contains several separate sections of
logic, each clocked according to its own clock frequency requirements. See each peripheral device
section for more details. The section below describes the clocking for both the ARM720T and address/data bus.
2.7.1
Note:
2.7.1.1
When the clock frequency is selected to be
36 MHz, both the ARM720T and the address/data
buses are clocked at 36 MHz. When the clock frequency is selected higher than 36 MHz, only the
ARM720T gets clocked at this higher speed. The
address/data will be fixed at 36 MHz. The clock
frequency used is selected by programming the
CLKCTL[1:0] bits in the SYSCON3 register. The
clock frequency selection does not effect the EPB
(external peripheral bus). Therefore, all the periph-
After modifying the CLKCTL[1:0] bits, the next
instruction should always be a ‘NOP’.
Characteristics of the PLL Interface
When connecting a crystal to the on-chip PLL interface pins (i.e. MOSCIN and MOSCOUT), the
crystal and circuit should conform to the following
requirements:
•
A 3.6864 MHz fundamental mode crystal
should be used.
•
A start-up resistor is not necessary, since one is
provided internally.
•
Start-up loading capacitors may be placed on
each side of the external crystal and ground.
Their value should be in the range of 10 pF.
However, their values should be selected based
upon the crystal specifications. The total sum of
the capacitance of the traces between the
CS89712’s clock pins, the capacitors, and the
crystal leads should be subtracted from the
crystal’s specifications when determining the
values for the loading capacitors.
•
The crystal frequency drift should be less than
100 ppm over the operating temperature range.
On-Chip PLL
The ARM720T clock can be programmed to
18.432 MHz, 36.864 MHz, 49.152 MHz, or
73.728 MHz with the PLL running at 147456 MHz,
twice the highest possible CPU clock frequency.
The PLL uses an external 3.6864 MHz crystal. By
default, the address/data buses run at 18.432 MHz.
16
eral clocks are fixed, regardless of the clock speed
selected for the ARM720T.
Alternatively, a digital clock source can be used to
drive the MOSCIN pin of the CS89712. With this
approach, the voltage levels of the clock source
should match that of the VDD supply for the
CS89712’s pads (i.e. the supply voltage level used
to drive all of the non-VDD core pins on the
CS89712). The output clock pin (i.e., MOSCOUT)
should be left floating.
DS502PP2
CS89712
2.7.2
Dynamic Clock Switching
The clock frequency used for the CPU and the buses is controlled by programming the CLKCTL[1:0]
bits in the SYSCON3 register. When this register is
written, clock switching logic waits until the clock
that is currently in use and the newly programmed
clock source are both low, and then switches from
the previous clock frequency to the new clock without a glitch on the clocks.
2.7.3
Ethernet Port Clock Oscillator
A 20 MHz quartz crystal or CMOS clock input is
required by the Ethernet port. If a CMOS clock input is used, it should be connected the to XTAL1
pin, with the XTAL2 pin left open. The clock signal should be 20 MHz ±0.01% with a duty cycle
between 40% and 60%. The specifications for the
crystal are described in Section 5.3.
2.8 Interrupt Controller
When unexpected events arise during the execution
of a program (i.e., interrupt or memory fault) an exception is usually generated. When these exceptions occur at the same time, a fixed priority system
determines the order in which they are handled.
Table 6 shows the priority order of the exceptions.
Priority
Exception
Highest
Reset
.
Data Abort
.
FIQ
.
IRQ
.
Prefetch Abort
Lowest
Undefined Instruction,
Software Interrupt
Table 6. Exception Priority Handling
The CS89712 interrupt controller has two interrupt
types: interrupt request (IRQ) and fast interrupt request (FIQ). The interrupt controller has the ability
to control interrupts from 22 different FIQ and IRQ
sources. Of these, seventeen are mapped to the IRQ
input and five sources are mapped to the FIQ input.
FIQs have a higher priority than IRQs. If two interrupts are received from within the same group (IRQ
or FIQ), the order in which they are serviced must
be resolved in software. All interrupts are level sensitive; that is, they must conform to the following
sequence:
1) The interrupting device (either external or internal) asserts the appropriate interrupt.
2) If the appropriate bit is set in the interrupt mask
register, then either a FIQ or an IRQ will be as-
EXPCLK
(internal)
RUN
CLKEN
t42
Interrupt /
WAKEUP
Note: t42=0.125 sec. to 0.25 sec.
Figure 4. CLKEN Timing Exiting the Standby State
DS502PP2
17
CS89712
serted by the interrupt controller. (A description for each bit in this register can be found in
Section 3.6.1.
3) If interrupts are enabled the processor will
jump to the appropriate address.
4) Interrupt dispatch software reads the interrupt
status register to establish the source(s) of the
interrupt and calls the appropriate interrupt service routine(s).
5) Software in the interrupt service routine will
clear the interrupt source by some action specific to the device requesting the interrupt (i.e.,
reading the UART RX register).
18
The interrupt service routine may then re-enable interrupts, and any other pending interrupts will be
serviced in a similar way. Alternately, it may return
to the interrupt dispatch code, which can check for
any more pending interrupts and dispatch them accordingly. The “End of Interrupt” type interrupts
are latched. All other interrupt sources (i.e., external interrupt source) must be held active until its respective service routine starts executing. See
Section 3.13, “End Of Interrupt Locations” for
more details.
Table 7, Table 8, and Table 9 show the names and
allocation of interrupts in the CS89712.
DS502PP2
CS89712
Interrupt
Bit in INTMR1 and
INTSR1
Name
Comment
FIQ
0
EXTFIQ
FIQ
1
BLINT
Battery low interrupt
FIQ
2
WEINT
Tick Watchdog expired interrupt
FIQ
3
MCINT
Media changed interrupt
IRQ
4
CSINT
Codec sound interrupt
IRQ
5
EINT1
External interrupt input 1 (nEINT[1] pin)
IRQ
6
EINT2
External interrupt input 2 (nEINT[2] pin)
IRQ
8
TC1OI
TC1 underflow interrupt
IRQ
9
TC2OI
TC2 underflow interrupt
IRQ
10
RTCMI
RTC compare match interrupt
IRQ
11
TINT
IRQ
12
UTXINT1
Internal UART1 transmit FIFO empty interrupt
IRQ
13
URXINT1
Internal UART1 receive FIFO full interrupt
IRQ
14
UMSINT
Internal UART1 modem status changed interrupt
IRQ
15
SSEOTI
Synchronous serial interface 1 end of transfer interrupt
External fast interrupt input (nEXTFIQ pin)
64 Hz tick interrupt
Table 7. Interrupt Allocation in the First Interrupt Register
Interrupt
Bit in INTMR2 and
INTSR2
Name
Comment
IRQ
0
KBDINT
Key press interrupt
IRQ
1
SS2RX
Master / slave SSI 16 bytes received
IRQ
2
SS2TX
Master / slave SSI 16 bytes transmitted
IRQ
12
UTXINT2
UART2 transmit FIFO empty interrupt
IRQ
13
URXINT2
UART2 receive FIFO full interrupt
Table 8. Interrupt Allocation in the Second Interrupt Register
Interrupt
Bit in INTMR3 and
INTSR3
Name
FIQ
0
DAIINT
Comment
DAI interface interrupt
Table 9. Interrupt Allocation in the Third Interrupt Register
DS502PP2
19
CS89712
2.8.1
2.8.1.1
Interrupt Latencies
Operating State
The ARM720T core checks for a low level on its
FIQ and IRQ inputs at each instruction boundary.
The interrupt latency is therefore directly related to
the amount of time it takes to complete execution
of the current instruction when the interrupt condition is detected. First, there is a one to two clock cycle synchronization penalty. For the case where the
CS89712 is operating with a 16-bit external memory system, and the program stored in one wait
state FLASH memory, the worst-case interrupt latency is 251 clock cycles. This includes a delay for
cache line fills for instruction prefetches, and a data
abort occurring at the end of the LDM instruction,
and the LDM being non-quad word aligned. In addition, the worst-case interrupt latency assumes
that LCD DMA cycles to support a panel size of
320 x 240 at 4 bits-per-pixel, 60 Hz refresh rate, is
in progress. This would give a worst-case interrupt
latency of about 3.4 µs for 74 MHz operation. For
operation at different frequencies and/or with
32 bit wide external memory, the latency will
change accordingly.
For the nMEDCHG signal, this figure is substantially increased by the maximum time required to
pass through the deglitcher, approximately 125 µs
(2 cycles of the 16.384 kHz clock derived from the
RTC oscillator). This results in an absolute worstcase latency of approximately 128 µs. Refer to
Table 10 for a summary.
All the serial data transfer peripherals included in
the CS89712 (except for the master-only SSI1)
have local buffering to ensure a reasonable interrupt latency response requirement for the OS of <
1 ms. This assumes that the design data rates do not
exceed the data rates described in this specification.
If the OS cannot meet this requirement, there will
be a risk of data over/underflow occurring.
20
2.8.1.2
Idle State
When leaving the Idle State as a result of an interrupt, the CPU clock is restarted after approximately
two clock cycles. However, there is still potentially
up to a 251 clock latency as described in the first
section above, unless the code is written to include
at least two single cycle instructions immediately
after the write to the IDLE register (in which case
the latency drops to a few microseconds). This is
important, as the Idle State can only be left because
of a pending interrupt, which has to be synchronized by the processor before it can be serviced.
2.8.1.3
Standby State
In the Standby State, the latency will depend on
whether the system clock is shut down and if the
FASTWAKE bit in the SYSCON3 register is set. If
the system is configured to run from the internal
PLL clock, then the PLL will always be shut down
when in the Standby State. In this case, if the
FASTWAKE bit is cleared, then there will be a latency of between 0.125 sec to 0.25 sec. If the
FASTWAKE bit is set, then there will be a latency
of between 250 µsec to 500 µsec.
Whenever the CS89712 is in the Standby State, the
external address and data buses are driven low. The
RUN signal is used internally to force these buses
to be driven low. This prevents de-powered peripherals from draining current. Also, the internal peripheral’s signals are set to their Reset State.
2.8.1.4
Snooze State
In Snooze State, the latency will be reduced to the
same as for the Idle State described above. This is
true at any frequency because the PLL or external
clock source is not stopped. All clocks except the
minimum required for LCD refresh from the internal SRAM are disabled to save further power.
To drastically reduce the potential worst case latency when leaving Snooze State to a few microseconds, ensure that the code contains two single cycle
DS502PP2
CS89712
instructions immediately after the write to the
SNOOZE register location.
2.8.1.5
Doze State
Since Doze State can be considered a preliminary
state between Snooze State and Operating State,
the only requirement for existing this state into the
Operating State is for a few instructions to be executed. Therefore, the latency is based solely upon
the time required to execute these instructions.
Table 10 summarizes the five external interrupt
sources and their effect on the processor interrupts.
2.9 Boot ROM
The 128 bytes of on-chip Boot ROM contain an instruction sequence that initializes the device and
then configures UART1 to receive 2048 bytes of
serial data that will then be placed in the on-chip
SRAM. Once the download is complete, execution
jumps to the start of the on-chip SRAM. This
would allow, for example, code to be downloaded
to program system FLASH during a product’s
manufacturing process. See Section , “Appendix B:
Boot Code” for details of the ROM Boot Code with
comments to describe the stages of execution.
Interrupt
Pin
Input State
Operating State
Latency
nEXTFIQ
Not deglitched; must be Worst-case 3.4 µsec
active for 251 clock
at 74 MHz
cycles to ensure detection
nEINT1–2
Not deglitched
nMEDCHG
Deglitched by 16 kHz
Worst-case latency
clock; must be active
of 128 µsec at 74
for at least 125 µs to be MHz
detected
Selection of the Boot ROM option is determined by
the state of the nMEDCHG pin during a power on
reset. If nMEDCHG is high while nPOR is active,
then the CS89712 will boot from an external memory device connected to CS[0] (normal boot mode).
If nMEDCHG is low, then the boot will be from the
on-chip ROM. Note that in both cases, following
the de-assertion of nPOR, the CS89712 will be in
the Standby State and require a low-to-high transition on the external WAKEUP pin in order to actually start the boot sequence.
The effect of booting from the on-chip Boot ROM
is to reverse the decoding for all chip selects internally. Table 11 shows this decoding. The control
signal for the boot option is latched by nPOR,
which means that the remapping of addresses and
bus widths will continue to apply until nPOR is asserted again. After booting from the Boot ROM,
the contents of the Boot ROM can be read back
from address 0x0000.0000 onwards, and in normal
state of operation the Boot ROM contents can be
read back from address range 0x7000.0000.
2.10 Memory Map
The lower 2 GByte of the address space is allocated
to memory. The 512 MBytes of address space from
Idle State
Latency
Worst-case 251
clocks: if only
single cycle
instructions, less
than 1 µsec
Worst-case 3.4 µsec As above
at 74 MHz
Worst-case
80 µsec: if only
single cycle
instructions,
125 µsec
Standby State Latency
Including PLL / osc. settling time, ~
0.25 sec when FASTWAKE = 0, or
approx. 500 µsec when FASTWAKE = 1
As above
As above
Table 10. External Interrupt Source Latencies
DS502PP2
21
CS89712
Address Range
MMU should be programmed to generate an abort
exception for access to this area.
Chip Select
0000.0000–0FFF.FFFF
CS[7]
(Internal only)
1000.0000–1FFF.FFFF
CS[6]
(Internal only)
2000.0000–2FFF.FFFF
nCS[5]
3000.0000–3FFF.FFFF
nCS[4]
4000.0000–4FFF.FFFF
nCS[3]
5000.0000–5FFF.FFFF
nCS[2]
6000.0000–6FFF.FFFF
nCS[1]
7000.0000–7FFF.FFFF
nCS[0]
Internal peripherals are addressed through a set of
internal registers from address 0x8000.0000 to
0x8000.3FFF.
Table 11. Chip Select Address Ranges After Boot From
On-Chip Boot ROM
0xC000.0000 to 0xDFFF.FFFF is allocated to
SDRAM. The 1.5 GByte, less 8 kbytes for internal
registers, is not accessible in the CS89712. The
Table 12 shows how the 4-Gbyte address range of
the ARM720T processor (as configured within this
chip) is mapped. The memory map shown assumes
that two CL-PS6700 PC Card controllers are connected. If this functionality is not required, then the
nCS[4] and nCS[5] memory is available. The external boot ROM is not fully decoded (i.e., the boot
code will repeat within the 256 Mbyte space from
0x7000.0000 to 0x8000.0000).
When booted from on chip boot ROM, the SRAM
is fully decoded up to 128 kbytes. Access to any location above this range will wrap within the range.
Address
Contents
Size
0xF000.0000
Reserved
256 Mbytes
0xE000.0000
Reserved
256 Mbytes
0xD000.0000
Reserved
256 Mbytes
0xC000.0000
SDRAM
64 Mbytes
0x8000.4000
Unused
~1 Gbyte
0x8000.2000
Internal registers
8 kbytes
0x8000.0000
Internal registers
8 kbytes
0x7000.0000
Boot ROM (nCS[7])
128 bytes
0x6000.0000
SRAM (nCS[6])
48k bytes
0x5000.0000
PCMCIA-1 (nCS[5])
4 x 64 Mbytes
0x4000.0000
PCMCIA-0 (nCS[4])
4 x 64 Mbytes
0x3000.0000
Expansion (nCS[3])
256 Mbytes
0x2000.0000-0x2000.02FF
Expansion (nCS[2])
0x2000.0300-0x2000.030F
Ethernet Port (on nCS[2])
0x2000.0310-0x2FFF.FFFF
Expansion (nCS[2]) cont.
0x1000.0000
ROM Bank 1 (nCS[1])
256 Mbytes
0x0000.0000
ROM Bank 0 (nCS[0])
256 Mbytes
256 Mbytes
Table 12. CS89712 Memory Map in External Boot Mode
22
DS502PP2
CS89712
2.11 Memory and I/O Expansion Interface
Six separate linear memory or expansion segments
are decoded by the CS89712, two of which can be
reserved for two PC Cards, each interfacing to a
separate single CL-PS6700 device. Each segment
is 256 Mbytes in size. Two additional segments (in
addition to these six) are dedicated to the on-chip
SRAM and ROM. The on-chip ROM space is fully
decoded, and the SRAM space is decoded up to the
maximum size of the video frame buffer programmed in the LCDCON register (128 kbytes).
Beyond this address range the SRAM space is not
fully decoded (i.e., any accesses beyond 128 kbyte
range get wrapped around to within 128 kbyte
range). Any of the six segments are configured to
interface to a conventional SRAM-like interface,
and can be individually programmed to be 8-, 16-,
or 32-bits wide, to support page mode access, and
to execute from 1 to 8 wait states for non-sequential
accesses and 0 to 3 for burst mode accesses. The
zero wait state sequential access feature is designed
to support burst mode ROMs. For writable memory
devices which use the nMWE pin, zero wait state
sequential accesses are not permitted and one wait
state is the minimum which should be programmed
in the sequential field of the appropriate MEMCFG
register. Bus cycles can also be extended using the
EXPRDY input signal.
Page mode access is accomplished by setting
SQAEN = 1, enabling accesses of one random address followed by three sequential addresses, etc.,
while keeping nCS asserted. These sequential
bursts can be up to four words long before nCS is
released to allow DMA and refreshes to take place.
This can significantly improve bus bandwidth to
devices such as ROMs which support page mode.
When SQAEN = 0, all accesses to memory are by
random access without nCS being de-asserted between accesses. Again nCS is de-asserted after four
consecutive accesses to allow DMA.
DS502PP2
Bits 5 and 6 of the SYSCON2 register independently enable the interfaces to the CL-PS6700 (PC Card
slot drivers). When either of these interfaces are enabled, the corresponding chip select (nCS4 and/or
nCS5) becomes dedicated to that CL-PS6700 interface. The state of SYSCON2 bit 5 determines the
function of chip select nCS4 (i.e., CL-PS6700 interface or standard chip select functionality); bit 6
controls nCS5 in a similar way. There is no interaction between these bits.
For applications that require a display buffer smaller than 48k bytes, the on-chip SRAM can be used
as the frame buffer.
Before entering the Snooze State, the SRAM at
0x6000.0000 must be updated, under program control, with data to be displayed during the Snooze
State. In a system using the on-chip SRAM as the
frame buffer in normal operation, Snooze State can
be entered without requiring any data transfer first,
assuming data is stored in the on-chip SRAM in 1bit -per-pixel format.
The width of the boot device can be chosen by selecting values of PE[1] and PE[0] during power on
reset. The inputs in Table 13 are latched by the rising edge of nPOR to select the boot option.
PE[1]
PE[0]
Boot Block
(nCS0)
0
0
32-bit
0
1
8-bit
1
0
16-bit
1
1
Undefined
Table 13. Boot Options
2.12 SDRAM Controller
The SDRAM controller provides all the connections to directly interface to up to two banks of
SDRAM, and the width of the memory interface is
programmable from 16 to 32 bits wide. Both banks
have to be of the same width. Each of the two banks
supported can be up to 256 Mbits in size. The sig23
CS89712
nals nRAS nCAS, and nWE are provided for
SDRAM. Two chip selects are provided for supporting up to 2 rows of SDRAMs. The SDRAM
devices are put into self-refresh mode when the
SDRAM controller is put into standby. The
SDRAM clock is halted as well.
Chip selects for row 1 SDRAMs should be connected to nSDCS[0]. If row 2 is used, these devices
should connect to nSDCS[1].
For 32-bit memory access, four SDQM data byte
mask selects are provided to control individual byte
lanes within each row. For 16-bit memory access
only, SDQM[1:0] are used. For a 32-bit memory
access configuration with each row containing two
16-bit wide SDRAMs, the high order SDRAM
should have UDQM (upper SDQM) connected to
SDQM[3] and LDQM (lower SDQM) connected to
SDQM[2]. The low order SDRAM follows the
same convention: USDQM is connected to
SDQM[1], and LDQM is connected to SDQM[0].
The controller supports read, write, refresh, precharge and mode register write requests to the
SDRAM. Data is transferred to and from the
SDRAM as unbroken quad accesses (either quad
word or for 16 bit memory, quad halfword), which
is a convenient data packet size for the ARM cache
line fills. For the CPU to read smaller than a quad
access, the SDRAM controller will discard the extra data. For CPU writes smaller than a quad access, the SDQM pins (SDRAM data byte mask
selects) are used to force the SDRAMs to ignore invalid data. For CPU access sizes larger than a quad
access, multiple quad accesses are issued to the
SDRAM.
Memory address line multiplexing is done internally so that the address mapping is contiguous.
Table 16 indicates how the SDRAM address pins
are connected to the CPU’s address pins. Note that
small SDRAM devices will not use all of these
pins. For example, A[12:11] may not be required.
However, the bank select pins BA[1:0], are required by all SDRAMs. Smaller devices may only
have one bank, so BA1 may not be needed.
The SDRAM controller can access a total memory
size of 2-64 Mbytes. Each individual SDRAM
should be NEC or compatible SDRAM memory in
sizes of 16-256 Mbits, arranged as shown in
Table 14 and Table 15.
Arrangement of SDRAMs
(C = # Columns of SDRAM, R = # Rows of SDRAM, D = # of SDRAMs)
SDRAM details
4 Mbytes
Density
(Mbits)
Width
(bits)
16
4
C
R
8 Mbytes
D
8
16
64
C
4
2
1
R
1
16 Mbytes
D
C
R
D
8
1
8
C
R
D
C
R
D
8
1
8
4
2
8
4
1
4
2
4
16
32
64 Mbytes
4
8
128
32 Mbytes
1
1
1
2
1
2
1
2
2
4
1
4
2
2
4
4
8
Table 14. SDRAM Configurations (SDRAM 32-Bit Memory Interface)
24
DS502PP2
CS89712
16
256
2
1
2
2
2
4
2
1
2
4
8
16
Table 14. SDRAM Configurations (SDRAM 32-Bit Memory Interface)
SDRAM Details
Arrangement of SDRAMs
(C = # Columns of SDRAM, R = # Rows of SDRAM, D = # of SDRAMs)
2 Mbytes
Density
(Mbits)
Width
(bits)
16
4
C
R
D
8
16
64
4 Mbytes
C
2
1
1
R
1
D
8 Mbytes
C
R
D
4
1
4
32 Mbytes
64 Mbytes
C
C
R
D
C
R
D
4
1
4
4
2
8
2
2
4
4
1
4
2
2
4
2
1
2
1
2
2
R
D
2
1
4
8
16
128
16 Mbytes
1
1
1
2
1
2
1
2
2
4
8
16
256
1
1
1
2
1
2
1
2
2
4
8
16
1
1
1
Table 15. SDRAM Configurations (SDRAM 16-Bit Memory Interface)
DS502PP2
25
CS89712
SDRAM Address
Pins
CS89712 Pin Names
3) Once the precharge is complete, and the minimum tRP is satisfied, the mode register can be
programmed. After the mode register set cycle,
tRSC (2 CLK minimum) pause must be satisfied as well. (Only required for NEC SDRAM)
A0.
a27/dra0
A1.
a26/dra1
A2.
a25/dra2
A3.
a24/dra3
A4.
a23/dra4
2.14 CL-PS6700 PC Card Interface
A5.
a22/dra5
A6.
a21/dra6
A7.
a20/dra7
A8.
a19/dra8
A9.
a18/dra9
A10.
a17/dra10
A11.
a16/dra11
A12.
a15/dra12
BA0.
a14/dra13
BA1.
a13/dra14
Two of the expansion memory areas are dedicated
to supporting up to two CL-PS6700 PC Card controller devices. These are selected by nCS4 and
nCS5 (must first be enabled by bits 5 and 6 of
SYSCON2). For efficient, low power operation,
both address and data are carried on the lower 16
bits of the CS89712 data bus. Accesses are initiated
by a write or read from the area of memory allocated for nCS4 or nCS5. The memory map within
each of these areas is segmented to allow different
types of PC Card accesses to take place, for attribute, I/O, and common memory space. The CLPS6700 internal registers are memory mapped
within the address space as shown in Table 17.
4) Eight or more refresh cycles must be performed.
Table 16. SDRAM Address Pin Connections
2.13 SDRAM Initialization
The SDRAM is initialized in the power-on sequence as follows:
1) To stabilize internal circuits when power is applied, a 200+ µs pause must precede any signal
toggling.
2) After the pause, all banks must be precharged
using the Precharge command (including the
precharge all banks command).
Access Type
Note:
Due to the operating speed of the CL-PS6700,
this interface is supported only for a processor
speed of 18 MHz.
A complete description of the protocol and AC timing characteristics can be found in the CL-PS6700
data sheet. A transaction is initiated by an access to
the nCS4 or nCS5 area. The chip select is asserted,
and on the first clock, the upper 10 bits of the PC
Card address, along with 6 bits of size, space, and
slot information are put out onto the lower 16 bits
Addresses for CL-PS6700 Interface 1
Addresses for CL-PS6700 Interface 2
Attribute
0x4000.0000–0x43FF.FFFF
0x5000.0000– 0x53FF.FFFF
I/O
0x4400.0000–0x47FF.FFFF
0x5400.0000–0x57FF.FFFF
Common memory
0x4800.0000–0x4BFF.FFFF
0x5800.0000–0x5BFF.FFFF
CL-PS6700 registers
0x4C00.0000–0x4FFF.FFFF
0x5C00.0000–0x5FFF.FFFF
Table 17. CL-PS6700 Memory Map
26
DS502PP2
CS89712
of the CS89712’s data bus. Only word (i.e., 4-byte)
and single-byte accesses are supported, and the slot
field is hardcoded to 11, since the slot field is defined as a ‘Reserved field’ by the CL-PS6700. The
chip selects are used to select the device to be accessed. The space field is made directly from the
A26 and A27 CPU address bits, according to the
decode shown in Table 18. The size field is forced
to 11 if a word access is required, or to 00 if a byte
access is required. This avoids the need to configure the interface after a reset. On the second clock
cycle, the remaining 16 bits of the PC Card address
are multiplexed out onto the lower 16 bits of the
data bus. If the transaction selected is a CL-PS6700
register transaction, or a write to the PC Card (assuming there is space available in the CL-PS6700’s
internal write buffer) then the access will continue
on the following two clock cycles. During these
following two clock cycles the upper and lower
halves of the word to be read or written will be put
onto the lower 16 bits of the main data bus.
The ‘ptype’ signal on the CL-PS6700s should be
connected to the CS89712’s WRITE output pin.
During PC Card accesses, the polarity of this pin
changes, and it becomes low to signify a write and
high to signify a read. It is valid with the first half
word of the address. During the second half word
of the address, it is always forced high to indicate
to the CL-PS6700 that the CS89712 has initiated
either the write or read.
The PRDY signals from each of the two CLPS6700 devices are connected to Port B bits 0 and
1, respectively. When the PC CARD1 or PC
CARD2 control bits in the SYSCON2 register are
de-asserted, these port bits are available for GPIO.
When asserted, these port bits are used as the
PRDY signals. When the PRDY signal is de-asserted (i.e., low), it indicates that the CL-PS6700 is
busy accessing its card. If a PC CARD access is attempted while the device is busy, the PRDY signal
will cause the CS89712’s CPU to be stalled. The
CS89712’s CPU will have to wait for the card to
become available. DMA transfers to the LCD can
still continue in the background during this period
of time (as described below). The CS89712 can access the registers in the CL-PS6700, regardless of
the state of the PRDY signal. If the CS89712 needs
to access the PC CARD via the CL-PS6700, it
waits until the PRDY signal is high before initiating a transfer request. Once a request is sent, the
PRDY signal indicates if data is available.
In the case of a PC Card write, writes can be posted
to the CL-PS6700 device, with the same timing as
CL-PS6700 internal register writes. Writes will
normally be completed by the CL-PS6700 device
independent of the CS89712 processor activity. If a
posted write times out, or fails to complete for any
other reason, then the CL-PS6700 will issue an interrupt (i.e., a WR_FAIL interrupt). In the case
where the CL-PS6700 write buffer is already full,
the PRDY signal will be de-asserted (i.e., driven
low) and the transaction will be stalled pending an
available slot in the buffer. In this case, the
CS89712’s CPU will be stalled until the write can
Space Field Value
PC CARD Memory Space
00
Attribute
01
I/O
10
Common memory
11
CL-PS6700 registers
Table 18. Space Field Decoding
DS502PP2
27
CS89712
be posted successfully. While the PRDY signal is
de-asserted, the chip select to the CL-PS6700 will
be de-asserted and the main bus will be released so
that DMA transfers to the LCD controller can continue in the background.
In the case of a PC Card read, the PRDY signal
from the CL-PS6700 will be de-asserted until the
read data is ready. At this point, it will be reasserted
and the access will be completed in the same way
as for a register access. In the case of a byte access,
only one 16-bit data transfer will be required to
complete the access. While the PRDY signal is deasserted, the chip select to the CL-PS6700 will be
de-asserted, and the main bus will be released so
that DMA transfers to the LCD controller can continue in the background.
The CS89712 will re-arbitrate for the bus when the
PRDY signal is reasserted to indicate that the read
or write transaction can complete. The CPU will
stall until the PC Card access is completed.
A card read operation may be split into a request
cycle and a data cycle, or it may be combined into
a single request/data transfer cycle. This depends
on whether the requested data is available in the internal CL-PS6700 prefetch buffer.
The request portion of the cycle, for a card read, is
similar to the request phase for a card write (described above). If the requested data is available in
the prefetch buffer, the CL-PS6700 asserts the
PRDY signal before the rising edge of the third
clock and the CS89712 continues the cycle to read
the data. Otherwise, the PRDY signal is de-asserted, and the request cycle is stalled. The CS89712
may then allow the DMA address generator to gain
control of the bus, to allow LCD refreshes to continue. When the CL-PS6700 is ready with the data,
it asserts the PRDY signal. The CS89712 then arbitrates for the bus and, once the request is granted,
the suspended read cycle is resumed. The CS89712
resumes the cycle by asserting the appropriate chip
28
select, and data is transferred on the next two
clocks if a word read (one clock if a byte read).
There is no support within the CS89712 for detecting time-outs. The CL-PS6700 device must be programmed to force the cycle to be completed (with
invalid data for a read) and then generate an interrupt if a read or write access has timed out (i.e.,
RD_FAIL or WR_FAIL interrupt). The system
software can then determine which access was not
successfully completed by reading the status registers within the CL-PS6700.
The CL-PS6700 has support for DMA data transfers. However, DMA is supported only by software
emulation because the DMA address generator
built into the CS89712 is dedicated to the LCD
controller interface. If DMA is enabled within the
CL-PS6700, it will assert its PDREQ signal to
make a DMA request. This can be connected to one
of the CS89712’s external interrupts and be used to
interrupt the CPU for servicing the DMA request.
Each of the CL-PS6700 devices can generate an interrupt PIRQ. Since the PIRQ signal is an open
drain on the CL-PS6700 devices, two CL-PS6700
devices may be wired OR’ed to the same interrupt.
The circuit can then be connected to one of the
CS89712’s active low external interrupt sources.
On the receipt of an interrupt, the CPU can read the
interrupt status registers on the CL-PS6700 devices
to determine the cause of the interrupt.
All transactions are synchronized to the EXPCLK
output from the CS89712 in 18.432 MHz mode.
The EXPCLK should be permanently enabled, by
setting the EXCKEN bit in the SYSCON1 register,
when the CL-PS6700 is used. The reason for this is
that the PC Card interface and CL-PS6700 internal
write buffers need to be clocked after the CS89712
has completed its bus cycles.
A GPIO signal from the CS89712 can be connected
to the PSLEEP pin of the CL-PS6700 devices to allow them to be put into a power saving state before
the CS89712 enters the Standby State. It is essenDS502PP2
CS89712
Address (W/B) Data in Memory
(as seen by the
CS89712)
Byte Lanes to Memory / Ports / Registers
Big Endian Memory
R0 Contents
Little Endian Memory
7:0 15:8 23:16 31:24 7:0 15:8 23:16 31:24 Big Endian Little Endian
Word + 0 (W)
11223344
44
33
22
11
44
33
22
11
11223344
11223344
Word + 1 (W)
11223344
44
33
22
11
44
33
22
11
44112233
44112233
Word + 2 (W)
11223344
44
33
22
11
44
33
22
11
33441122
33441122
Word + 3 (W)
11223344
44
33
22
11
44
33
22
11
22334411
22334411
Word + 0 (H)
11223344
dc
dc
22
11
44
33
dc
dc
00001122
00003344
Word + 1 (H)
11223344
dc
dc
22
11
44
33
dc
dc
22000011
44000033
Word + 2 (H)
11223344
44
33
dc
dc
dc
dc
22
11
00003344
00001122
Word + 3 (H)
11223344
44
33
dc
dc
dc
dc
22
11
44000033
22000011
Word + 0 (B)
11223344
dc
dc
dc
11
44
dc
dc
dc
00000011
00000044
Word + 1 (B)
11223344
dc
dc
22
dc
dc
33
dc
dc
00000022
00000033
Word + 2 (B)
11223344
dc
33
dc
dc
dc
dc
22
dc
00000033
00000022
Word + 3 (B)
11223344
44
dc
dc
dc
dc
dc
dc
11
00000044
00000011
Note: dc = don’t care
Table 19. Effect of Endianness on Read Operations
tial that software monitors the appropriate status
registers within the CL-PS6700s to ensure that
there are no pending posted bus transactions before
the Standby State is entered. Failure to do this will
result in incomplete PC Card accesses.
2.15 Endianness
The CS89712 uses a little endian configuration for
internal registers. However, it is possible to connect the device to a big endian external memory
system. The big-endian / little-endian bit in the
ARM720T control register sets whether the
CS89712 treats words in memory as being stored in
big endian or little endian format. Memory is
viewed as a linear collection of bytes numbered upwards from zero. Bytes 0 to 3 hold the first stored
word, bytes 4 to 7 the second, and so on. In the little
endian scheme, the lowest numbered byte in a word
is considered to be the least significant byte of the
DS502PP2
word and the highest numbered byte is the most
significant. Byte 0 of the memory system should be
connected to D[7:0] in this case. In the big endian
scheme the most significant byte of a word is stored
at the lowest numbered byte, and the least significant byte is stored at the highest numbered byte.
Therefore, byte 0 of the memory system should be
connected to D[31:24]. Load and store are the only
instructions affected by the Endianness.
Table 19 and Table 20 demonstrate the behavior of
the CS89712 for read and write operations, including the effect of performing non-aligned word accesses. The register definition section defines the
behavior of the internal CS89712 registers in the
big endian mode in more detail. For further information, refer to ARM Application Note 61, “Big
and Little Endian Byte Addressing”.
29
CS89712
Address
(W/B)
Register
Contents
Byte Lanes to Memory / Ports / Registers
Big Endian Memory
Little Endian Memory
7:0
15:8
23:16
31:24
7:0
15:8
23:16
31:24
Word + 0 (W)
11223344
44
33
22
11
44
33
22
11
Word + 1 (W)
11223344
44
33
22
11
44
33
22
11
Word + 2 (W)
11223344
44
33
22
11
44
33
22
11
Word + 3 (W)
11223344
44
33
22
11
44
33
22
11
Word + 0 (H)
11223344
44
33
44
33
44
33
44
33
Word + 1 (H)
11223344
44
33
44
33
44
33
44
33
Word + 2 (H)
11223344
44
33
44
33
44
33
44
33
Word + 3 (H)
11223344
44
33
44
33
44
33
44
33
Word + 0 (B)
11223344
44
44
44
44
44
44
44
44
Word + 1 (B)
11223344
44
44
44
44
44
44
44
44
Word + 2 (B)
11223344
44
44
44
44
44
44
44
44
Word + 3 (B)
11223344
44
44
44
44
44
44
44
44
Note: Bold indicates active byte lane.
Table 20. Effect of Endianness on Write Operations
2.16 Internal UARTs and SIR Encoder
The CS89712 contains two built-in UARTs that offers similar functionality to National Semiconductor’s 16C550A device. Both UARTs can support
bit rates of up to 115.2 kbits/s and include two 16byte FIFOs: one for receive and one for transmit.
One of the UARTs (UART1) supports the three
modem control input signals CTS, DSR, and DCD.
The additional RI input, and RTS and DTR output
modem control lines are not explicitly supported
but can be implemented using GPIO ports in the
CS89712. UART2 has only the RX and TX pins.
UART operation and line speeds are controlled by
the UBLCR1 (UART bit rate and line control).
Three interrupts can be generated by UART1: RX,
TX, and modem status interrupts. Only two can be
generated by UART2: RX and TX. The RX interrupt is asserted when the RX FIFO becomes half
full or if the FIFO is non-empty for longer than
three character length times with no more charac30
ters being received. The TX interrupt is asserted if
the TX FIFO buffer reaches half empty. The modem status interrupt for UART1 is generated if any
of the modem status bits change state. Framing and
parity errors are detected as each byte is received
and pushed onto the RX FIFO. An overrun error
generates an RX interrupt immediately. All error
bits can be read from the 11-bit wide data register.
The FIFOs can also be programmed to be one byte
depth only (i.e., like a conventional 16450 UART
with double buffering).
The CS89712 also contains an IrDA (Infrared Data
Association) SIR protocol encoder as a post-processing stage on the output of UART1. This encoder can be optionally switched into the TX and RX
signals of UART1, so that these can be used to
drive an infrared interface directly. If the SIR protocol encoder is enabled, the UART TXD1 line is
held in the passive state and transitions of the
RXD1 line will have no effect. The IrDA output pin
DS502PP2
CS89712
is LEDDRV, and the input from the photodiode is
PHDIN. Modem status lines will cause an interrupt
(which can be masked) irrespective of whether the
SIR interface is being used.
Both the UARTs operate in a similar manner to the
industry standard 16C550A. When CTS is deasserted on the UART, the UART does not stop shifting the data. It relies on software to make an
appropriate response to the interrupt generated.
Baud rates supported for both the UARTs are dependent on frequency of operation. When operating from the internal PLL, the interface supports
various baud rates from 115.2 kbits/s downwards.
The master clock frequency is chosen so that most
of the required data rates are obtainable exactly.
Type
Comments
2.17 Synchronous Serial Interfaces
The CS89712 has the synchronous serial interfaces
shown in Table 21. Three sets of serial interface
(DAI, CODEC, and SSI2) pins are multiplexed together. On power up, both the DAISEL and SERSEL register bits are low, enabling the master /
slave SSI2 to these pins (and configuring it for
slave mode operation to avoid external contention).
Table 22 contains pin definition information for the
three multiplexed interfaces.
The internal names given to each of the three interfaces are unique to help differentiate them from
each other. The sections below that describe each
of the three interfaces will use their respective
unique internal pin names for clarity.
Referred To As
Max. Transfer Speed
SPI / Microwire 1
Master mode only
ADC Interface
128 kbits/s
SPI / Microwire 2
Master / slave mode
SSI2 Interface
512 kbits/s
DAI Interface
CD quality DACs and ADCs
DAI Interface
1.536 Mbits/s
CODEC
Interface
64 kbits/s
CODEC Interface
Table 21. Serial Interface Options
BGA
Ball
External
Pin Name
SSI2
Slave Mode
(Internal Name)
SSI2
Master Mode
CODEC
Internal Name
DAI
Internal Name
Strength
SSICLK
SSICLK = serial bit
clock; Input
Output
PCMCLK =
Output
SCLK =
Output
1
SSITXFR
SSITXFR = TX
frame sync; Input
Output
PCMSYNC = Output
LRCK = Output
1
SSITXDA
SSITXDA = TX
data; Output
Output
PCMOUT = Output
SDOUT = Output
1
SSIRXDA
SSIRXDA = RX
data; Input
Input
PCMIN = Input
SDIN = Input
SSIRXFR
SSIRXFR = RX
frame sync; Input
Output
p/u
(use a 10k pull-up)
MCLK
1
Table 22. Serial-Pin Assignments
DS502PP2
31
CS89712
that the interrupt generation will occur 1 msec
after one of the FIFOs is enabled. For example:
If the receive FIFO gets enabled first and the
transmit FIFO at a later time, the interrupt will
occur 1 msec after the receive FIFO is enabled.
After the first interrupt occurs, the receive FIFO
will be half full. However, it will not be possible
to know how full the transmit FIFO will be since
it was enabled at a later time. Thus, it is
possible to unintentionally overwrite data
already in the transmit FIFO (See Figure 5).
2.17.1 Codec Sound Interface
The codec interface allows direct connection of a
telephony type codec to the CS89712. It provides
all the necessary clocks and timing pulses. It also
performs a parallel to serial conversion or vice versa on the data stream to or from the external codec
device. The interface is full duplex and contains
two separate data FIFOs (16 deep by 8-bits, one for
the receive data, another for the transmit data).
Data is transferred to or from the codec at
64 kbits/s. The data is either written to or read from
the appropriate 16-byte FIFO. If enabled, a codec
interrupt (CSINT) will be generated after every
8 bytes are transferred (FIFO half full/empty). This
means the interrupt rate will be every 1 msec, with
a latency of 1 msec.
Transmit and receive modes are enabled by asserting high both the CDENRX and CDENTX codec
enable bits in the SYSCON1 register.
Note:
Both the CDENRX and CDENTX enable bits
should be asserted in tandem for data to be
transmitted or received. The reason for this is
2.17.1.1 Codec Interrupt Timing
After the CDENRX and CDENTX enable bits are
asserted, the corresponding FIFOs become enabled. When both FIFOs are disabled, the FIFO status flag CRXFE is set and CTXFF is cleared so that
the FIFOs appear empty. Additionally, if the
CDENTX bit is low, the PCMOUT output is disabled. Asserting either of the enable bits causes the
sync and interrupt generation logic to activate; otherwise they are disabled to conserve power.
Data is loaded into the transmit FIFO by writing to
the CODR register. At the beginning of a transmit
cycle, this data is loaded into a shift/load register.
CDENRX
CDENTX
CSINT
1 ms
Interrupt occurs
Interrupt occurs
1 ms
Interrupt occurs
1 ms
Figure 5. Codec Interrupt Timing
32
DS502PP2
CS89712
Just prior to the byte being transferred out, PCMSYNC goes high for one PCMCLK cycle. Then the
data is shifted out serially to PCMOUT, MSB first,
(with the MSB valid at the same time PCMSYNC
is asserted). Data is shifted on the rising edge of the
PCMCLK output.
Receiving of data is performed by taking data in serially through PCMIN, again MSB first, shifting it
through the shift/load register and loading the complete byte into the receive FIFO. If there is no data
available in the transmit FIFO, then a zero will be
loaded into the shift/load register. Input data is
sampled on the falling edge of PCMCLK. Data is
read from the CODR register.
Note:
After data is transmitted, the speaker amplifier
should be turned off to avoid audible noise. This
is needed because the CS89712 will continue
to transmit data from the FIFO even though it is
empty, thus causing noise. This will occur even
when receiving.
2.17.2 Digital Audio Interface
The DAI interface provides a high quality digital
audio connection to DAI compatible audio devices.
The DAI is a subset of I2S audio format that is supported by a number of manufacturers.
The DAI interface produces one 128-bit frame at
the audio sample frequency using a bit clock and
frame sync signal. Digital audio data is transferred,
full duplex, via separate transmit and receive data
lines. The bit clock frequency is programmable to
DAI 128/64 fs
CODEC
SSI2
64 fs or 128 fs. The sample frequency (fs) is now
programmable from 8-48Khz using either the onchip PLL (73.728MHz) or the external 11.2896
Mhz clock.
The DAI interface contains separate transmit and
receive FIFO’s. The transmit FIFO’s are 8 audio
samples deep and the receive FIFO’s are 12 audio
samples deep.
DAI programming centers around the selection of
the desired sample frequency (fs). All three clocks
(MCLK, LRCK, SCLK) become a multiple of the
selected sample frequency as illustrated on the previous page. The DAI share the same output with the
CODEC and SSI as shown in Figure 6. Please see
Table 23 for the MUX programming matrix.
2.17.2.1 DAI Operation
Following reset, the DAI logic is disabled. To enable the DAI, the applications program should first
clear the emergency underflow and overflow status
bits, which are set following the reset, by writing a
1 to these register bits (in the DAISR register).
Next, the DAI control register should be programmed with the desired mode of operation using
a word write. The transmit FIFOs can either be
“primed” by writing up to eight 16-bit values each,
or can be filled by the normal interrupt service routine which handles the DAI FIFOs. Finally, the
FIFOs for each channel must be enabled via writes
to DAIDR2. At this point, transmission/reception
of data begins on the transmit (SDOUT) and re-
SSICLK,
SSITXFR,
SSITXDA,
SSIRXDA ,
SSIRSFR
Figure 6. Portion of the CS89712 Block Diagram Showing Multiplexed Feature
DS502PP2
33
CS89712
ceive (SDIN) pins. This is synchronously controlled by either the PLL or the external clock.
These fixed frequencies pass through a programmable divider network which will create the appropriate values for SCLK, LRCLK, and MCLK for
the desired sample frequency. Examples of sample
frequencies are shown in Table 24. Register
DAI64Fs enables/disables the bit clock frequency
of 64 fs (and the other features as shown in Figure
7), but must be complemented by SYSCON3 bit 9
which will enable/disable 128 fs. To enable one
rate, you must disable the other.
2.17.2.2 DAI Frame Format
Each DAI frame is 128 bits long and comprises one
audio sample. Of this 128-bit frame, only 32 bits
are used for digital audio data. The remaining bits
are output as zeros. The LRCK signal is used as a
FEATURE
SYSCON3
DAIR (DAI)
DAI64 fs
SYSCON2
DAI –128 fs
DAISEL[3] (H)
DAIEN[16] (H)
I2SF64[0] (L)
(X)
DAIEN[16] (H)
I2SF64[0] (H)
(X)
128Fs[9] (H)
DAI-64 fs
DAISEL[3] (H)
128Fs[9] (L)
SSI2
DAISEL[3] (L)
DAIEN[16] (L)
(X)
SERSEL[0] (L)
CODEC
DAISEL[3] (L)
DAIEN[16] (L)
(X)
SERSEL[0] (H)
Table 23. Matrix for Programming the MUX
Note: To connect the port to any of the 4 features shown above, a minimum software configuration shown in the
table above must be observed. Each register column contains the bit name (bit #) that must be cleared or
set for each feature as shown in the column. This table does not complete the programming for each of the
features, but allows access to the port only. The interrupt masks for these features will have to be
programmed as well.
128 fs
Audio Bit
Clock (MHz)
64 fs
Audio Bit
Clock (MHz)
Clock Source
(MHz)
Sample
Frequency (KHz)
128 fs Divisor
(AUDDIV)
64 fs Divisor
(AUDDIV)
1.0240
0.5120
73.728
8
36
72
1.4112
0.7056
11.2896
11.025
8
16
1.5360
0.7680
73.728
16
18
36
2.8224
1.4112
11.2896
22.025
4
8
3.0720
1.5360
73.728
24
12
24
4.0960
2.0480
73.728
32
9
18
5,6448
2.8224
11.2896
44.1
2
4
6.1440
3.0720
73.728
48
6
12
Table 24. Relationship between Audio Clocks / Clock Source / Sample Frequencies
34
DS502PP2
CS89712
Programmable Divide
(AUDIV)
MUX
(AUDCLKSRC)
PLL
(73.728MHz)
128(fs)
/2
Audio
Sample
7-bit
counter Frequency
fixed at 4
(fs)
/32
Audio
Data
FIFO
Control
Audio Bit Clock 128/64(fs) SCLK
DAI
EXTCLK
(11.2896)
LRCLK(Fs)
256Fs
MCLK
BUZZ-PIN
BUZZ
Figure 7. Digital Audio Clock Generation
128 SCLKs
Left Channel
LRCK
Right Channel
SCLK
SDATA O
MSB
-1 -2 -3 -4 -5
+5 +4 +3 +2 +1
LSB
MSB
-1 -2 -3 -4
+5 +4 +3 +2 +1
SDATAI
MSB
-1 -2 -3 -4 -5
+5 +4 +3 +2 +1
LSB
MSB
-1 -2 -3 -4
+5 +4 +3 +2 +1
LSB
LSB
Figure 8. CS89712 - Digital Audio Interface Timing – MSB / Left Justified format
frame synchronization. Each transition of LRCK
delineates the left and right halves of an audio sample. When LRCK transitions from high-to-low the
next 16 bits make up the right side of a sample.
When LRCK transitions from low-to-high the next
16 bits make up the left side of a sample.
2.17.2.3 DAI Signals
MCLK is used as an input to the CS89712 for generating the DAI timing. This signal is also usually
used as an input to a DAC/ADC as an oversampled
clock. This signal is fixed at 256 times the audio
sample frequency.
DS502PP2
The SCLKbit clock is used as the bit clock input
into the DAC/ADC. This signal is fixed at 128 or
64 times the audio sample frequency.
LRCK is used as a frame synchronization input to
the DAC/ADC. This signal is fixed at the audio
sample frequency. This signal is clocked out on the
negative going edge of SCLK.
SDOUT is used for sending playback data to a
DAC. This signal is clocked out on the negative going edge of the SCLK output.
SDIN is used for receiving record data from an
ADC. This signal is latched by the CS89712 on the
positive going edge of SCLK.
35
CS89712
2.17.3 ADC Interface - SSI1 Master Only
The first synchronous serial interface allows interfacing to the following peripheral devices:
•
•
•
In the default mode, the device is compatible
with the MAXIM MAX148/9 in external clock
mode. Similar SPI- or Microwire-compatible
devices can connect directly to the CS89712.
In the extended mode and with negative-edge
triggering selected (the ADCCON and ADCCKNSEN bits are set, respectively, in the
SYSCON3 register), this device can be interfaced to Analog Devices’ AD7811/12 chip using nADCCS as a common RFS/TFS line.
Other features of the devices, including power
management, can be utilized by software and
the use of the GPIO pins.
The clock output frequency is programmable and
only active during data transmissions to save power. There are four output frequencies selectable.
The required frequency is selected by programming the corresponding bits 16 and 17 in the
SYSCON1 register. The sample clock (SMPCLK)
always runs at twice the frequency of the shift
clock (ADCCLK). The output channel is fed by an
8-bit shift register when the ADCCON bit of
SYSCON3 is clear. When ADCCON is set, up to
16 bits of configuration command can be sent, as
specified in the SYNCIO register. The input channel is captured by a 16-bit shift register. The clock
and synchronization pulses are activated by a write
to the output shift register. During transfers the
SSIBUSY (synchronous serial interface busy) bit
in the system status flags register is set. When the
transfer is complete and valid data is in the 16-bit
read shift register, the SSEOTI interrupt is asserted
and the SSIBUSY bit is cleared.
An additional sample clock (SMPCLK) can be enabled independently and is set at twice the transfer
clock frequency.
This interface has no local buffering capability and
is only intended to be used with low bandwidth interfaces, such as for a touch-screen ADC interface.
2.17.4 SSI2 with Master / Slave operation
A second SPI / Microwire interface with full master/slave capability is provided by the CS89712.
Data rates in slave mode are theoretically up to
512 kbits/s, full duplex, although continuous operation at this data rate will give an interrupt rate of
2 kHz, too fast for many operating systems. This
would require a worst-case interrupt response time
of less than 0.5 msec and would cause loss of data
through TX underruns and RX overruns.
The interface is fully capable of being clocked at
512 kHz when in slave mode. However, it is anticipated that external hardware will be used to frame
the data into packets. Therefore, although the data
would be transmitted at a rate of 512 kbits/s, the
sustained data rate would in fact only be
85.3 kbits/s (i.e., 1 byte every 750 µsec). At this
SYSCON1
bit 17
SYSCON1
bit 16
18.432–73.728 MHz Operation
ADCCLK Frequency (kHz)
0
0
4
0
1
16
1
0
64
1
1
128
Table 25. ADC Interface Operation Frequencies
36
DS502PP2
CS89712
data rate, the required interrupt rate will be greater
than 1 msec, which is acceptable.
There are separate half-word-wide RX and TX
FIFOs (16 half-words each) and corresponding interrupts which are generated when the FIFO’s are
half-full or half-empty as appropriate. The interrupts are called SS2RX and SS2TX, respectively.
Register SS2DR is used to access the FIFOs.
There are five pins to support this SSI port: SSIRXDA, SSITXFR, SSICLK, SSITXDA, and SSIRXFR. The SSICLK, SSIRXDA, SSIRXFR, and
SSITXFR signals are inputs and the SSITXDA signal is an output in slave mode. In the master mode,
SSICLK, SSITXDA, SSITXFR, and SSIRXFR are
outputs, and SSIRXDA is an input. Master mode is
enabled by writing a one to the SS2MAEN bit
(SYSCON2[9]). When the master / slave SSI is not
required, it can be disabled to save power by writing a zero to the SS2TXEN and the SS2RXEN bits
(SYSCON2[4] [7]). When set, these two bits independently enable the transmit and receive sides of
the interface. The master/slave SSI is synchronous,
full duplex, and capable of supporting serial data
transfers between two nodes. Although the interface is byte-oriented, data is loaded in blocks of
two bytes at a time. Each data byte to be transferred
is marked by a frame sync pulse, lasting one clock
Slave 7211
period, and located one clock prior to the first bit
being transferred. Direction of the SSI2 ports, in
slave and master mode, is shown in Figure 9.
Data on the link is sent MSB first and coincides
with an appropriate frame sync pulse, one clock in
duration, located one clock prior to the first data bit
(MSB). It is not possible to send data LSB first.
When operating in master mode, the clock frequency is selected to be the same as the ADC interface’s
(master mode only SSI1) — that is, the frequencies
are selected by the same bits 16 and 17 of the
SYSCON1 register (i.e., the ADCKSEL bits).
Thus, the maximum frequency in master mode is
128 kbits/s. The interface will support continuous
transmission at this rate assuming that the OS can
respond to the interrupts within 1 msec to prevent
over/underruns.
Note:
To allow synchronization to the incoming slave
clock, the interface enable bits will not take
effect until one SSICLK cycle after they are
written and the value read back from
SYSCON2. The enable bits reflect the real
status of the enables internally. Hence, there
will be a delay before the new value
programmed to the enable bits can be read
back.
The timing diagram for this interface can be found
in Section 6.3.
Master 7211
SSIRXFR
SSIRXFR
SSITXFR
SSITXFR
SSICLK
SSICLK
SSIRXDA
SSITXDA
SSITXDA
SSIRXDA
Figure 9. SSI2 Port Directions in Slave and Master Mode
DS502PP2
37
CS89712
2.17.4.1 Read Back of Residual Data
All writes to the transmit FIFO must be in halfwords (i.e., in units of two bytes at a time). On the
receive side, it is possible that an odd number of
bytes will be received. Bytes are always loaded into
the receive FIFO in pairs. Consequently, in the case
of a single residual byte remaining at the end of a
transmission, it will be necessary to read the byte
separately. This is done by reading the status of two
bits in the SYSFLG2 register to determine the validity of the residual data. These two bits (RESVAL, RESFRM) are both set high when a residual
is valid. RESVAL is cleared on either a new transmission or on reading of the residual bit by software. RESFRM is cleared only on a new
transmission. By popping the residual byte into the
RX FIFO and then reading the status of these bits it
is possible to determine if a residual bit has been
correctly read.
Figure 10 illustrates this procedure. The sequence
is as follows: read the RESVAL bit, if this is a 0, no
action needs to be taken. If this is a 1, then pop the
residual byte into the FIFO by writing to the
SS2POP location. Then read back the two status
bits RESVAL and RESFRM. If these bits read back
01, then the residual byte popped into the FIFO is
valid and can be read back from the SS2DR register. If the bits are not 01, then there has been anoth-
er transmission received since the residual read
procedure has been started. The data item that has
been popped to the top of the FIFO will be invalid
and should be ignored. In this case, the correct byte
will have been stored in the most significant byte of
the next half-word to be clocked into the FIFO.
Note:
All the writes / reads to the FIFO are done word
at a time (data on the lower 16 bits is valid and
upper 16 bits are ignored).
Software manually pops the residual byte into the
RX FIFO by writing to the SS2POP location (the
value written is ignored). This write will strobe the
RX FIFO write signal, causing the residual byte to
be written into the FIFO.
2.17.4.2 Support for Asymmetric Traffic
The interface supports asymmetric traffic (i.e., unbalanced data flow). This is accomplished through
separate transmit and receive frame sync control
lines. In operation, the receiving node receives a
byte of data on the eight clocks following the assertion of the receive frame sync control line. In a similar fashion, the sending node can transmit a byte of
data on the eight clocks following the assertion of
the transmit frame sync pulse. There is no correlation in the frequency of assertions of the RX and
TX frame sync control lines (SSITXFR and
SSIRXFR). Hence, the RX path may bear a greater
data throughput than the TX path, or vice versa.
Residual bit valid
00
11
New RX byte received
Pop FIFO
New RX byte
received
01
Figure 10. Residual Byte Reading
38
DS502PP2
CS89712
Both directions, however, have an absolute maximum data throughput rate determined by the maximum possible clock frequency, assuming that the
interrupt response of the target OS is quick enough.
into the receiving device on the falling edge of the
clock. The TX pin is held in a tristate condition
when not transmitting.
2.17.4.3 Continuous Data Transfer
The LCD controller provides all the necessary control signals to interface directly to a single panel
multiplexed LCD.
Data bytes may be sent/received in a contiguous
manner without interleaving clocks between bytes.
The frame sync control line(s) are eight clocks
apart and aligned with the clock representing bit D0
of the preceding byte (i.e. one bit before the MSB).
2.17.4.4 Discontinuous Clock
In order to save power during the idle times, the
clock line is put into a static low state. The master
is responsible for putting the link into the Idle State.
The Idle State will begin one clock, or more, after
the last byte transferred and will resume at least one
clock prior to the first frame sync assertion. To disable the clock, the TX section is turned off.
In Master mode, the CS89712 does not support the
discontinuous clock.
2.17.4.5 Error Conditions
RX FIFO overflows are detected and conveyed via
a status bit in the SYSFLG2 register. This register
should be accessed at periodic intervals by the application software. The status register should be
read each time the RX FIFO interrupts are generated. At this time the error condition (i.e., overrun
flag) will indicate that an error has occurred but
cannot convey which byte contains the error. Writing to the SRXEOF register location clears the
overrun flag. TX FIFO underflow condition is detected and conveyed via a bit in the SYSFLG2 register, which is accessed by the application software.
A TX underflow error is cleared by writing data to
be transmitted to the TX FIFO.
2.17.4.6 Clock Polarity
Clock polarity is fixed. TX data is presented on the
bus on the rising edge of the clock. Data is latched
DS502PP2
2.18 LCD Controller
The panel size is programmable and can be any
width (line length) from 32 to 1024 pixels in 16pixel increments. The total video frame buffer size
is programmable up to 128 kbytes. This equates to
a theoretical maximum panel size of 1024 x
256 pixels in 4 bits-per-pixel mode. The video
frame buffer can be located in any portion of memory controlled by the chip selects. Its start address
will be fixed at address 0x0000.0000 within each
chip select. The start address of the LCD video
frame buffer is defined in the FBADDR[3:0] register. These bits become the most significant nibble
of the external address bus. The default start address is 0xC000.0000 (FBADDR = 0xC).
A system built using the on-chip SRAM (OCSR),
will then serve as the LCD video frame buffer and
miscellaneous data store. The LCD video frame
buffer start address should be set to 0x6 in this option. Programming of the register FBADDR is only
permitted when the LCD is disabled (this is to
avoid possible cycle corruption when changing the
register contents while a LCD DMA cycle is in
progress). There is no hardware protection to prevent this. It is necessary to disable the LCD controller before reprogramming the FBADDR register.
Full address decoding is provided for the OCSR, up
to the maximum video frame buffer size programmable into the LCDCON register. Beyond this, the
address is wrapped around. The frame buffer start
address must not be programmed to 0x4 or 0x5 if
either CL-PS6700 interface is in use (PCMEN1 or
PCMEN2 bits in the SYSCON2 register are enabled). FBADDR should never be programmed to
39
CS89712
0x7 or 0x8, as these are the locations for the onchip Boot ROM and internal registers.
During Snooze State, the shift clock (CL2), FRM,
and line (CL1) signals are on for the entire display.
The SNZDISP register is used to disable the data
path through the LCD controller after the required
data has been displayed, to save further power. After the word address stored in the SNZDISP register is reached, the data output pins DD[3:0] will be
blanked to 0 or 1 as defined by the SNZPOL bit,
which is at Bit 10 of the SYSCON2 register. Sections of the SRAM not used for the display data in
Snooze State can be used for other data storage.
In Snooze State, the LCD controller (if enabled via
the LCDEN bit in the SYSCON1 register) will automatically fetch data from the on-chip SRAM in
1-bit-per-pixel mode. Before entering Snooze
State, the required display buffer must be transferred into the on-chip SRAM in a 1-bit-per-pixel
format. On entry to Snooze State, the video frame
size field is reinterpreted for 1-bit-per-pixel data,
and the grey scale mode bits are ignored.
On exit from Snooze State, the CS89712 enters the
Doze State. In Doze State, all of the CS89712, except the LCD controller, is operating normally.
The DRAM is taken out of self-refresh and normal
CAS before RAS (CBR) refreshes start. The CPU
is active and takes interrupts at normal speed. In
Doze State, display data continues to be fetched
from the OCSR, as for the Snooze State. DMA for
the display is active only while the number of lines
programmed into the SNZDISP register are displayed and DMA/CPU arbitration is carried out
during this time. For the rest of the time, the LCD
controller displays “pixel fill” data on the LCD.
During the Doze State, if some of the OCSR memory space is not being used to store the video buffer,
the remaining section can be used by the CPU for
general purpose data storage. The remaining section is fully address decoded.
Note:
40
The only way to enter the Doze State is by exit
from the Snooze State. Also, the Snooze State
cannot exit directly to the Operating State; it
must go through the Doze State first.
In an application, the CS89712 would spend most
of its time in snooze mode. On interrupt or wakeup, it moves into Doze State. At this point the OS
identifies the cause of the interrupt and decides
whether it can stay in Doze State (e.g., update a
clock on the display) or if it is woken up because
the user wants to perform a function requiring the
full display. In the latter case, the OS will set the
LCDSNZE bit low and the CS89712 will switch to
the Operating State. In the Operating State, the display will be automatically switched to the main
frame buffer on the next frame sync. The full LCD
controller is used and data fetched from the buffer
pointed to by the FBADDR register (if LCDSNZE
is low). To ensure correct synchronization it is not
possible to program the LCDSNZE bit to high with
software, this is done automatically as part of the
process of entering the Snooze State. It can, however, be set low from software. This is how the display is changed back to the main display after exit
from the Snooze State, if this is required.
It is likely that system software would normally
wake up from the Snooze State for two reasons: 1)
to perform minor OS functions like updating a time
display or polling the keyboard, and 2) to wake up
completely because the user has pressed a key. In
the former case, the LCDSNZE bit would be left
high and the Snooze State re-entered by writing to
the SNOOZE location in the normal way. The chip
would continue to output data from the on-chip
SRAM throughout (which could have been updated
while out of Snooze State). In the second case,
software should write to the LCDSNZE location
soon after exiting from Snooze State. Then the
LCD controller will be re-enabled and the display
cleanly switched across to the main frame buffer as
pointed to by the address in the FBADDR register.
The screen is mapped to the video frame buffer as
one contiguous block where each horizontal line of
DS502PP2
CS89712
pixels is mapped to a set of consecutive bytes or
words in the video RAM. The video frame buffer
can be accessed word wide as pixel 0 is mapped to
the LSB in the buffer such that the pixels are arranged in a little endian manner.
The pixel bit rate, and hence the LCD refresh rate,
can be programmed from 18.432 MHz to 576 kHz.
The LCD controller is programmed by writing to
the LCD control register (LCDCON). The LCDCON register should not be reprogrammed while
the LCD controller is enabled.
The LCD controller also contains two 32-bit palette
registers, which allow any 4-, 2-, or 1-bit pixel value to be mapped to any of the 15 grayscale values
available. The palette registers are bypassed in
Snooze State.
The required DMA bandwidth to support a ½ VGA
panel displaying 4 bits-per-pixel data at an 80 Hz
refresh rate is approximately 6.2 Mbytes/sec. Assuming the frame buffer is stored in a 32-bit wide
the maximum theoretical bandwidth available is
86 Mbytes/sec at 36.864 MHz.
The LCD controller uses a nine stage 32-bit wide
FIFO to buffer display data. The LCD controller requests new data when there are five words remaining in the FIFO. This means that for a ½ VGA
display at 4 bits-per-pixel and 80 Hz refresh rate,
the maximum allowable DMA latency is approximately 3.25 µsec ((5 words x 8 bits/byte) / (640 x
240 x 4 bpp x 80 Hz)) = 3.25 µsec). The worst-case
latency is the total number of cycles from when the
DMA request appears to when the first DMA data
word actually becomes available at the FIFO.
DMA has the highest priority, so it will always happen next in the system. The maximum number of
cycles required is 36 from the point at which the
DMA request occurs to the point at which the STM
is complete, then another 6 cycles before the data
actually arrives at the FIFO from the first DMA
read. This creates a total of 42 cycles assuming the
frame buffer is located in 32-bit wide memory.
DS502PP2
With 16-bit wide memory, the worst-case latency
will double. In this case, the maximum permissible
display size may be halved, to approximately 320 x
240 pixels, depending on required pixel depth and
refresh rate. If 18 MHz mode is selected with 32-bit
wide memory, then the worst-case latency will be
2.26 µsec (i.e., 42 cycles x 54 nsec/cycle). If
36 MHz mode is selected, and 32-bit wide, then the
worst-case latency drops down to 1.49 µs. If the
frame buffer is to be stored in static memory, then
further calculations must be performed. This calculation is a little more complex for 36 MHz mode of
operation. The total number of cycles = (12 x 4) +
7 = 55. Thus, 55 x 27 ns = ~1.49 µsec.
Figure 11 shows the organization of the video map
for all combinations of bits-per-pixel.
The refresh rate is not affected by the number of
bits-per-pixel; however the LCD controller fetches
twice the data per refresh for 4 bits-per-pixel compared to 2 bits-per-pixel. The main reason for reducing the number of bits-per-pixel is to reduce the
power consumption of the memory where the video
frame buffer is mapped.
2.19 Timer Counters
Two identical timer counters are integrated into the
CS89712. These are referred to as TC1 and TC2.
Each timer counter has an associated 16-bit read /
write data register and some control bits in the system control register. Each counter is loaded with
the value written to the data register immediately.
This value will then be decremented on the second
active clock edge to arrive after the write (i.e., after
the first complete period of the clock). When the
timer counter under flows (i.e., reaches 0), it will
assert its appropriate interrupt. The timer counters
can be read at any time. The clock source and mode
are selectable by writing to bits in the system control register. 512 kHz and 2 kHz rates are provided.
The timer counters can operate in two modes: free
running or pre-scale.
41
CS89712
2.19.1 Free Running Mode
In the free running mode, the counter will wrap
around to 0xFFFF when it under flows and it will
continue to count down. Any value written to TC1
or TC2 will be decremented on the second edge of
the selected clock.
under flows. Any value written to TC1 or TC2 will
be decremented on the second edge of the selected
clock. This mode can be used to produce a programmable frequency to drive the buzzer (i.e., with
TC1) or generate a periodic interrupt. The formula
is F=(500 kHz) / (n+1).
2.19.2 Prescale Mode
2.20 Real-Time Clock
In the prescale mode, the value written to TC1 or
TC2 is automatically re-loaded when the counter
The CS89712 contains a 32-bit Real-Time Clock
(RTC). This can be written to and read from in the
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale
Bit 0 Bit 1
Gray scale
Bit 2 Bit 3 Bit 4
Bit 5 Bit 6 Bit 7
4 Bits per pixel
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale Gray scale
Bit 0
Gray scale
Bit 1 Bit 2 Bit 3 Bit 4
Gray scale
Bit 5 Bit 6 Bit 7
2 Bits per pixel
Pixel 1 Pixel 2 Pixel 3 Pixel 4
Gray scale
Gray scale
Gray scale Gray scale
Bit 0 Bit 1
Bit 2 Bit 3 Bit 4
Bit 5 Bit 6 Bit 7
1 Bit per pixel
Figure 11. Video Buffer Mapping
42
DS502PP2
CS89712
same way as the timer counters, but is 32 bits wide.
The RTC is always clocked at 1 Hz, generated from
the 32.768 kHz oscillator. It also contains a 32-bit
output match register, this can be programmed to
generate an interrupt when the count in the RTC
matches a specific value written to this register.
The RTC can only be reset by an nPOR cold reset.
Because the RTC data register is updated from the
1 Hz clock derived from the 32 kHz source, which
is asynchronous to the main memory system clock,
the data register should always be read twice to ensure a valid and stable reading. This also applies
when reading back the RTCDIV field of the
SYSCON1 register, which reflects the status of the
six LSBs of the RTC counter.
2.20.1 RTC Interface Characteristics
When connecting a crystal to the RTC interface
pins (i.e., RTCIN and RTCOUT), the crystal and
circuit should conform to the following:
•
The 32.768 kHz frequency should be created
by the crystals fundamental tone (i.e., it should
be a fundamental mode crystal)
•
A start-up resistor is not necessary, since one is
provided internally.
•
Start-up loading capacitors may be placed on
each side of the external crystal and ground.
Their value should be in the range of 10 pF.
However, their values should be selected based
upon the crystal specifications. The total sum of
the capacitance of the traces between the
CS89712’s clock pins, the capacitors, and the
crystal leads should be subtracted from the
crystal’s specifications when determining the
values for the loading capacitors.
•
The crystal should have a maximum 5 ppm frequency drift over the chip’s operating temperature range.
•
The voltage for the crystal must be 2.5 V + 0.2 V.
DS502PP2
Alternatively, a digital clock source can be used to
drive the RTCIN pin of the CS89712. With this approach, the voltage levels of the clock source
should match that of the VDD supply for the
CS89712’s pads (i.e., the supply voltage level used
to drive all of the non-VDD core pins on the
CS89712) (i.e., RTCOUT). The output clock pin
should be left floating.
2.21 Dedicated LED Flasher
The LED flasher feature enables an external pin
(PD[0] / LEDFLSH) to be toggled at a programmable rate and duty ratio for connection to an LED.
This module is driven from the RTCs 32.768 kHz
oscillator and works in all running modes because
no CPU intervention is needed once its rate and
duty ratio have been configured (via the LEDFLSH
register). The LED flash rate period can be programmed for 1, 2, 3, or 4 seconds. The duty ratio
can be programmed such that the mark portion can
be 1/16 to 16/16 of the full cycle.
2.22 PWM Interfaces
Two Pulse Width Modulator (PWM) duty ratio
clock outputs are provided in the CS89712. When
the device is operating from the internal PLL, the
PWM will run at a frequency of 96 kHz. These signals are intended for use as drives for external DCto-DC converters in the Power Supply Unit (PSU)
subsystem. External input pins that would normally
be connected to the output from comparators monitoring the external DC-to-DC converter output are
also used to enable these clocks. These are the
FB[1:0] pins. The duty ratio (and hence PWMs on
time) can be programmed from 1 in 16 to 15 in 16.
The sense of the PWM drive signal (active high or
low) is determined by latching the state of this
drive signal during power on reset (i.e., a pull-up on
the drive signal will result in a active low drive output, and visa versa). This allows either positive or
negative voltages to be generated by the external
DC-to-DC converter.The DC to DC converter
channels remain enabled in Snooze State. In
43
CS89712
Snooze State these are the only peripherals apart
from the LCD controller and on-chip SRAM to remain enabled. If either or both of the converters are
not required, they should be switched off before entering Snooze State to save power. PWMs are disabled by writing zeros into the drive ratio fields in
the PMPCON Pump Control register.
to be transmitted and when to start transmission
(i.e. after 5, 381, 1021 or all bytes have been transferred). Following the Transmit Command is the
Transmit Length, indicating how much buffer
space is required. When buffer space is available,
the Ethernet frame is written into the Ethernet
port’s internal memory.
Note:
In the second phase of transmission, the Ethernet
port converts the frame into an Ethernet packet then
transmits it onto the network. The second phase begins with the Ethernet port transmitting the preamble and Start-of-Frame delimiter as soon as the
proper number of bytes has been transferred into its
transmit buffer (5, 381, 1021 bytes or full frame,
depending on configuration). The preamble and
Start-of-Frame delimiter are followed by the Destination Address, Source Address, Length field and
LLC data (all software supplied). If the frame is
less than 64 bytes, including CRC, the Ethernet
port adds pad bits if so configured. Finally, the
Ethernet port appends the proper 32-bit CRC value.
To maximize power savings, the drive ratio
fields should be used to disable the PWMs,
instead of the FB pins. The clocks that source
the PWMs are disabled when the drive ratio
fields are zeroed.
2.23 Ethernet Port Overview
The Ethernet port provides a flexible set of performance features and configuration options, allowing
designers to develop Ethernet circuits that meet
their system requirements.
The Ethernet Port performs two basic functions:
Ethernet packet transmission and reception. Before
transmission or reception is possible, the Ethernet
Port must be configured.
2.23.1 Configuration
The Ethernet port must be configured for packet
transmission and reception at power-up or reset.
Parameters must be written to its internal Configuration and Control registers. Configuration data can
either be written to the Ethernet port by software or
loaded automatically from an external EEPROM.
Section 2.24, “Programming the EEPROM” and
Section 2.6, “Ethernet EEPROM Configurations”
describe the configuration process in detail. Section 3.2.3, “Ethernet Status/Control Registers”
provides a detailed description of the bits in the
Configuration and Control Registers.
2.23.2 Packet Transmission
Packet transmission occurs in two phases. In the
first phase, the Ethernet frame is moved into the
Ethernet port’s buffer memory. The first phase begins with the issuance of a Transmit Command.
This informs the Ethernet port both that a frame is
44
Section 2.34, “Transmit Operation” provides a detailed description of packet transmission.
2.23.3 Packet Reception
Like packet transmission, packet reception occurs
in two phases. In the first phase, the Ethernet port
receives an Ethernet packet and stores it in on-chip
memory. The first phase of packet reception begins
with the receive frame passing through the analog
front end and Manchester decoder where Manchester data is converted to NRZ data. Next, the preamble and Start-of-Frame delimiter are stripped off
and the receive frame is sent through the address
filter. If the frame’s Destination Address matches
the criteria programmed into the address filter, the
packet is stored in the Ethernet port’s internal
memory. The Ethernet port then checks the CRC,
and depending on the configuration, informs the
processor that a frame has been received. In the
second phase, the receive frame is transferred into
host memory.
DS502PP2
CS89712
Section 2.32, “Basic Receive Operation” and Section 2.32.7, “Receive Ethernet Port Locations”
provide a detailed description of packet reception.
2.24 Programming the EEPROM
After initialization, software can access the EEPROM through the Ethernet port by writing one of
seven commands to the EEPROM Command register. Figure 12 shows the format of the EEPROM
Command register.
2.24.1 EEPROM Commands
The seven commands used to access the EEPROM
are: Read, Write, Erase, Erase/Write Enable,
Erase/Write Disable, Erase-All, and Write-All.
They are described in Table 26.
2.24.2 EEPROM Command Execution
During the execution of a command, the two Opcode bits, followed by the six bits of address (for a
’C46 or ’CS46) or eight bits of address (for a ’C56,
’CS56, ’C66 or ’CS66), are shifted out of the Ether-
net port, into the EEPROM. If the command is a
Write, the data in the EEPROM Data register
(Ethernet Port offset address 0042h) follows. If the
command is a Read, the data in the specified EEPROM location is written into the EEPROM Data
register. If the command is an Erase or Erase-All,
no data is transferred to or from the EEPROM Data
register. Before issuing any command, the SIBUSY bit (Register 16, SelfST, bit 8) must clear.
After each command has been issued, software
must wait again for SIBUSY to clear.
2.24.3 Enabling Access to the EEPROM
The Erase/Write Enable command provides protection from accidental writes to the EEPROM. The
software must write an Erase/Write Enable command before it attempts to write to or erase any EEPROM memory location. Once the software has
finished altering the contents of the EEPROM, it
must write an Erase/Write Disable command to
prevent unwanted modification of the EEPROM.
AD7 - AD0 used with ’C56,
’CS56, ’C66 and ’CS66
F
E
D
C
B
X
X
X
X
X
A
9
8
7
6
5
4
3
2
1
0
ELSEL OP1 OP0 AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0
AD5 - AD0 used with
’C46 and ’CS46
Bit
[F:B]
[A]
Name
ELSEL
[9:8]
[7:0]
OP1, OP0
AD7 to AD0
Description
Reserved
External Logic Select: When clear, the EECS pin is used to select the EEPROM.
When set, the ELCS pin is used to select the external LA decode circuit.
Opcode: Indicates what command is being executed (see next section).
EEPROM Address: Address of EEPROM word being accessed.
Figure 12. EEPROM Command Register Format
DS502PP2
45
CS89712
Command
Opcode
(bits 9,8)
EEPROM Address
(bits 7 to 0)
Data
EEPROM Type
Execution
Time
Read Register
1,0
word address
yes
all
25 µs
Write Register
0,1
word address
yes
all
10 ms
Erase Register
1.1
word address
no
all
10 ms
Erase/Write Enable
0,0
XX11-XXXX
no
‘CS46, ‘C46
9 µs
11XX-XXXX
no
‘CS56, ‘C56, ‘CS66, ‘C66
9 µs
0,0
0,0
XX00-XXXX
no
‘CS46, ‘C46
9 µs
00XX-XXXX
no
‘CS56, ‘C56, ‘CS66, ‘C66
9 µs
0,0
0,0
XX10-XXXX
no
‘CS46, ‘C46
10 ms
10XX-XXXX
no
‘CS56, ‘C56, ‘CS66, ‘C66
9 µs
0,0
0,0
XX01-XXXX
yes
‘CS46, ‘C46
10 ms
01XX-XXXX
yes
‘CS56, ‘C56, ‘CS66, ‘C66
10 ms
Erase/Write Disable
Erase-All Registers
Write-All Register
Table 26. EEPROM Commands
2.24.4 Writing and Erasing the EEPROM
2.25.2 LINKLED or HC0
To write data to the EEPROM, the software must
execute the following series of commands:
LINKLED or HC0 can be controlled by either the
Ethernet port or the software. When controlled by
the Ethernet port, LINKLED is low whenever the
Ethernet port receives valid 10BASE-T link pulses.
To configure this pin for software control, the
HC0E bit (SelfCTL register, Bit C) must be clear.
When controlled by the software, LINKLED is low
when the HCB0 bit (SelfCTL register, Bit E) is set.
To configure it for software control, the HC0E bit
must be set. Table 27 summarizes this operation.
1) Issue an Erase/Write Enable command.
2) Load the data into the EEPROM Data register.
3) Issue a Write command.
4) Issue an Erase/Write Disable command.
During the Erase command, the Ethernet port
writes FFh to the specified EEPROM location.
During the Erase-All command, the Ethernet port
writes FFh to all locations.
2.25 Ethernet LEDs
The Ethernet port provides three output pins that
can be used to control LEDs or external logic.
HC0E
(Bit C)
HCB0
(Bit E)
0
N/A
1
0
Pin configured as HC0:
Output is high
1
1
Pin configured as HC0:
Output is low
2.25.1 LANLED
LANLED goes low whenever the Ethernet port
transmits or receives a frame, or when it detects a
collision. LANLED remains low until there has
been no activity for 6 ms (i.e. each transmission, reception, or collision produces a pulse lasting a minimum of 6 ms).
46
Pin Function
Pin configured as LINKLED:
Output is low when valid
10BASE-T link pulses are
detected. Output is high if valid
link pulses are not detected
Table 27. LINKLED/HC0 Pin Operation
DS502PP2
CS89712
2.25.3 LED Connection
Each LED output is capable of sinking 10 mA to
drive an LED directly through a series resistor. The
output voltage of each pin is less than 0.4 V when
the pin is low.
2.26 Media Access Control Engine
2.26.1 Overview
The CS89712’s Ethernet Media Access Control
(MAC) engine is fully compliant with the IEEE
802.3 Ethernet standard (ISO/IEC 8802-3, 1993). It
handles all aspects of Ethernet frame transmission
and reception, including: collision detection, preamble generation and detection, and CRC generation and test. Programmable MAC features include
automatic retransmission on collision, and padding
of transmitted frames. The primary functions of the
MAC are: frame encapsulation and decapsulation;
error detection and handling; and, media access
management.
2.26.2 Frame Encapsulation/Decapsulation
The Ethernet port’s MAC engine automatically assembles transmit packets and disassembles receive
packets. It also determines if transmit and receive
frames are of legal minimum size.
2.26.2.1 Transmission
Once the proper number of bytes have been transferred to the Ethernet port’s memory (either 5, 381,
1021 bytes, or full frame), and providing that access to the network is permitted, the MAC automatically transmits the 7-byte preamble (1010101b...),
followed by the Start-of-Frame Delimiter (SFD,
10101011b), and then the serialized frame data. It
then transmits the Frame Check Sequence (FCS).
The data after the SFD and before the FCS (Destination Address, Source Address, Length, and data
field) is supplied by the software. FCS generation
by the Ethernet port may be disabled by setting the
InhibitCRC bit (TxCMD register, bit C).
Figure 13 shows the Ethernet frame format.
2.26.2.2 Reception
The MAC receives the incoming packet as a serial
stream of NRZ data from the Manchester encoder/decoder. It begins by checking for the SFD.
Once the SFD is detected, the MAC assumes all
subsequent bits are frame data. It reads the DA and
compares it to the criteria programmed into the address filter (see Section 2.32.7, “Receive Ethernet
Port Locations” for a description of Address Filtering). If the DA passes the address filter, the frame
is loaded into the Ethernet port’s memory. If the
BufferCRC bit (RxCFG register, bit B) is set, the
received FCS is also loaded into memory. Once the
entire packet has been received, the MAC validates
the FCS. If an error is detected, the CRCerror bit
(RxEvent register, Bit C) is set.
Packet
Frame
up to 7 bytes
alternating 1s / 0s
1 byte
SFD
6 bytes
6 bytes
DA
SA
preamble
2 bytes
Length Field
4 bytes
LLC data
Pad
FCS
frame length
min 64 bytes
max 1518 bytes
Direction of Transmission
SFD = Start of Frame Delimiter
DA = Destination Address
SA = Source Address
LLC = Logical Link Control
FCS = Frame Check Sequence (also
called Cyclic Redundancy Check, or CRC)
Figure 13. Ethernet Frame Format
DS502PP2
47
CS89712
2.26.2.3 Enforcing Minimum Frame Size
The MAC provides minimum frame size enforcement of both transmit and receive packets. When
the TxPadDis bit (TxCMD register, Bit D) is clear,
transmit frames will be padded with additional bits
to ensure that the receiving station receives a legal
frame (64 bytes, including CRC). When TxPadDis
is set, the Ethernet port will not add pad bits and
will transmit frames less that 64 bytes. If a frame is
received that is less than 64 bytes (including CRC),
the Runt bit (RxEvent register, Bit D) will be set indicating the arrival of an illegal frame.
2.26.3 Transmit Error Detection/Handling
The MAC engine monitors Ethernet activity and
reports and recovers from a number of error conditions. For transmission, the MAC reports the following errors in TxEvent (Register 8) and
BufEvent (Register C):
2.26.3.1 Out-of-Window (Late) Collision
If a collision is detected after the first 512 bits have
been transmitted, the MAC reports a late collision
by setting the Out-of-window bit (TxEvent register, Bit 9). The MAC then forces a bad CRC and
terminates the transmission. If the Out-of-windowiE bit (TxCFG register, Bit 9) is set, an interrupt is
generated. A late collision may indicate an illegal
network configuration.
2.26.3.2 Jabber Error
If a transmission continues longer than about
26 ms, the MAC disables the transmitter and sets
the Jabber bit (TxEvent register, Bit A). The output
of the transmitter returns to idle and remains there
until the software issues a new Transmit Command. If the JabberiE bit (TxCFG register, Bit A) is
set, an interrupt is generated. A Jabber condition indicates a possible error in the Ethernet port transmit
function. To prevent possible network faults, the
48
software should clear the transmit buffer. Possible
options include:
•
Reset the chip with either software or hardware
reset (see Section 2.24, “Programming the EEPROM”).
•
Issue a Force Transmit Command by setting the
Force bit (TxCMD register, bit 8).
•
Issue a Transmit Command with the TxLength
field set to zero.
2.26.3.3 Transmit Collision
The MAC counts the number of times an individual
packet must be retransmitted due to network collisions. The collision count is stored in bits B
through E of the TxEvent register. If the packet collides 16 times, transmission of that packet is terminated and the 16coll bit (TxEvent register, Bit F) is
set. If the 16colliE bit (TxCFG register, Bit F) is
set, an interrupt is generated on the 16th collision.
A running count of transmit collisions is recorded
in the TxCOL register.
2.26.3.4 Transmit Underrun
If the Ethernet port starts transmission of a packet
but runs out of data before reaching the end of
frame, the TxUnderrun bit (BufEvent register, Bit
9) is set. The MAC then forces a bad CRC and terminates the transmission. If the TxUnderruniE bit
(BufCFG bit 9) is set, an interrupt is generated.
2.26.4 Receive Error Detection/Handling
The following receive errors are reported in the RxEvent register:
2.26.4.1 CRC Error
If a frame is received with a bad CRC, the CRCerror bit (RxEvent register, Bit C) is set. If the
CRCerrorA bit (RxCTL register, Bit C) is set, the
frame will be buffered by Ethernet port. If the
CRCerroriE bit (RxCFG register. Bit C) is set, an
interrupt is generated.
DS502PP2
CS89712
2.26.4.2 Runt Frame
If a frame is received that is shorter than 64 bytes,
the Runt bit (RxEvent register, Bit D) is set. If the
RuntA bit (RxCTL register, Bit D) is set, the frame
will still be buffered by Ethernet port. If the RuntiE
bit (RxCFG bit D) is set, an interrupt is generated.
2.26.4.3 Extra Data
If a frame is received that is longer than 1518 bytes,
the Extradata bit (RxEvent register, Bit E) is set. If
the ExtradataA bit (RxCTL register, Bit E) is set,
the first 1518 bytes of the frame will still be buffered by Ethernet port. If the ExtradataiE bit (RxCFG register Bit E) is set, an interrupt is generated.
2.26.4.4 Dribble Bits and Alignment Error
Under normal operating conditions, the MAC may
detect up to 7 additional bits after the last full byte
of a receive packet. These bits, known as dribble
bits, are ignored. If dribble bits are detected, the
Dribblebit bit (RxEvent register, Bit 7) is set. If
both the Dribblebits bit and CRCerror bit (RxEvent
register Bit C) are set at the same time, an alignment error has occurred.
2.26.5 Media Access Management
The Ethernet network topology is a single shared
medium with several attached stations. The Ethernet protocol is designed to allow each station equal
access to the network at any given time. Any node
can attempt to gain access to the network by first
completing a deferral process (described below) after the last network activity, and then transmitting a
packet that will be received by all other stations. If
two nodes transmit simultaneously, a collision occurs and the colliding packets are corrupted. Two
primary tasks of the MAC are to avoid network collisions, and then recover when they occur.
2.26.5.1 Collision Avoidance
The MAC continually monitors network traffic by
checking for the presence of carrier activity (carrier
DS502PP2
activity is indicated by the assertion of the internal
Carrier Sense signal generated by the ENDEC). If
carrier activity is detected, the network is assumed
busy and the MAC must wait until the current
packet is finished before attempting transmission.
The Ethernet port supports two schemes for determining when to initiate transmission: Two-Part Deferral, and Simple Deferral. Selection of the
deferral scheme is determined by the 2-partDefDis
bit (LineCTL register bit D). If the 2-partDefDis bit
is clear, the MAC uses a two-part deferral process
defined in section 4.2.3.2.1 of the Ethernet standard
(ISO/IEC 8802-3, 1993). If the 2-partDefDis bit is
set, the MAC uses a simplified deferral scheme.
Both schemes are described below:
2.26.5.2 Two-Part Deferral
In the two-part deferral process, the 9.6 µs Inter
Packet Gap (IPG) timer is started whenever the internal Carrier Sense signal is deasserted. If activity
is detected during the first 6.4 µs of the IPG timer,
the timer is reset and then restarted once the activity has stopped. If there is no activity during the first
6.4 µs of the IPG timer, the IPG timer is allowed to
time out (even if network activity is detected during
the final 3.2 µs). The MAC then begins transmission if a transmit packet is ready and if it is not in
Backoff (Backoff is described later in this section).
If no transmit packet is pending, the MAC continues to monitor the network. If activity is detected
before a transmit frame is ready, the MAC defers to
the transmitting station and resumes monitoring the
network.
The two-part deferral scheme was developed to
prevent the possibility of the IPG being shortened
due to a temporary loss of carrier. Figure 14 diagrams the two-part deferral process.
2.26.5.3 Simple Deferral
In the simple deferral scheme, the IPG timer is
started whenever Carrier Sense is deasserted. Once
the IPG timer is finished (after 9.6 µs), if a transmit
49
CS89712
Start Monitoring
Network Activity
Start Monitoring
Network Activity
Yes
Yes
Network
Active?
Network
Active?
No
No
Wait
9.6 µ s
Start IPG
Timer
Yes
Wait
3.2 µ s
No
IPG
Timer =
6.4 µs?
Tx
Frame
No
Ready and Not
in Backoff?
No
Network
Active?
Yes
Yes
Network
Active?
No
Transmit
Frame
Yes
Figure 15. Simple Deferral
No
Tx
Frame
No
Ready and Not
in Backoff?
Network
Active?
Yes
Yes
Transmit
Frame
Figure 14. Two-Part Deferral
frame is pending and if the MAC is not in Backoff,
transmission begins the 9.6 µs IPG). If no transmit
packet is pending, the MAC continues to monitor
the network. If activity is detected before a transmit
frame is ready, the MAC defers to the transmitting
station and resumes monitoring the network. Figure 15 diagrams the simple deferral process.
2.26.5.4 Collision Resolution
If a collision is detected while the Ethernet port is
transmitting, the MAC responds in one of three
ways depending on whether it is a normal collision
(within the first 512 bits of transmission) or a late
collision (after the first 512 bits of transmission):
50
DS502PP2
CS89712
2.26.5.5 Normal Collisions
2.26.5.8 Standard Backoff
If a collision is detected before the end of the preamble and SFD, the MAC finishes the preamble
and SFD, transmits the jam sequence (32-bit pattern of all 0’s), and then initiates Backoff. If a collision is detected after the transmission of the
preamble and SFD but before 512 bit times, the
MAC immediately terminates transmission, transmits the jam sequence, and then initiates Backoff.
In either case, if the Onecoll bit (TxCMD register
bit 9) is clear, the MAC will attempt to transmit a
packet a total of 16 times (the initial attempt plus 15
retransmissions) due to normal collisions. On the
16th collision, it sets the 16coll bit (TxEvent register bit F) and discards the packet. If the Onecoll bit
is set, the MAC discards the packet without attempting any retransmission.
The Standard Backoff algorithm, also called the
"Truncated Binary Exponential Backoff", is described by the equation:
2.26.5.6 Late Collisions
If a collision is detected after the first 512 bits have
been transmitted, the MAC immediately terminates
transmission, transmits the jam sequence, discards
the packet, and sets the Out-of-window bit (TxEvent bit 9). The Ethernet port does not initiate
backoff or attempt to retransmit the frame. For additional information about Late Collisions, see Section 2.26.3.1, “Out-of-Window (Late) Collision” in
this section.
2.26.5.7 Backoff
After the MAC has completed transmitting the jam
sequence, it must wait, or "Back off", before attempting to transmit again. The amount of time it
must wait is determined by one of two Backoff algorithms: the Standard Backoff algorithm
(ISO/IEC 4.2.3.2.5) or the Modified Backoff algorithm. The algorithm used is selected by the ModBackoffE bit (LineCTL register bit B).
DS502PP2
0 ≤ r ≤ 2k
where r (a random integer) is the number of slot
times the MAC must wait (1 slot time = 512 bit
times), and k is the smaller of n or 10, where n is the
number of retransmission attempts.
2.26.5.9 Modified Backoff
The Modified Backoff is described by the equation:
0 ≤ r ≤ 2k
where r (a random integer) is the number of slot
times the MAC must wait, and k is 3 for n < 3 and
k is the smaller of n or 10 for n ≥ 3, where n is the
number of retransmission attempts.
The advantage of the Modified Backoff algorithm
over the Standard Backoff algorithm is that it reduces the possibility of multiple collisions on the
first three retries. The disadvantage is that it extends the maximum time needed to gain access to
the network for the first three retries.
The software may choose to disable the Backoff algorithm altogether by setting the DisableBackoff
bit (TestCTL register bit B). When disabled, the
Ethernet port only waits the 9.6 µs IPG time before
starting transmission.
2.27 Encoder/Decoder (ENDEC)
The Ethernet port’s integrated encoder/decoder
(ENDEC) circuit is compliant with the relevant
portions of section 7 of the Ethernet standard
(ISO/IEC 8802-3, 1993). Its primary functions include: Manchester encoding of transmit data; informing the MAC when valid receive data is
present (Carrier Detection); and, recovering the
clock and NRZ data from incoming Manchesterencoded data.
51
CS89712
2.27.3 Clock and Data Recovery
Figure 16 provides a diagram of the ENDEC and its
interface to the MAC and 10BASE-T transceiver.
When the receiver is idle, the phase-lock loop
(PLL) is locked to the internal clock signal. The assertion of the Carrier Sense signal interrupts the
PLL. When it restarts, it locks on the incoming data. The receive clock is then compared to the incoming data at the bit cell center and any phase
difference is corrected. The PLL remains locked as
long as the receiver input signal is valid. Once the
PLL has locked on the incoming data, the ENDEC
converts the Manchester data to NRZ and passes
the decoded data and the recovered clock to the
MAC for further processing.
2.27.1 Encoder
The encoder converts NRZ data from the MAC and
a 20 MHz Transmit Clock signal into a serial
stream of Manchester data. The Transmit Clock is
produced by an on-chip oscillator circuit that is
driven by either an external 20 MHz quartz crystal
or a TTL-level CMOS clock input. The encoded
signal is routed to the 10BASE-T transceiver.
2.27.2 Carrier Detection
The internal Carrier Detection circuit informs the
MAC that valid receive data is present by asserting
the internal Carrier Sense signal as soon it detects a
valid bit pattern (1010b or 0101b for 10BASE-T.
During normal packet reception, Carrier Sense remains asserted while the frame is being received,
and is deasserted 1.3 to 2.3 bit times after the last
low-to-high transition of the End-of-Frame (EOF)
sequence. Whenever the receiver is idle (no receive
activity), Carrier Sense is deasserted. The CRS bit
(LineST register bit E) reports the state of the Carrier Sense signal.
2.28 10BASE-T Transceiver
The Ethernet port includes an integrated 10BASET transceiver that is compliant with the relevant
portions of section 14 of the Ethernet standard
(ISO/IEC 8802-3, 1993). It includes all analog and
digital circuitry needed to interface the Ethernet
port directly to a simple isolation transformer (see
the Characteristics/Specifications section for a connection diagram). Figure 17 provides a block diagram of the 10BASE-T transceiver.
2.28.1 10BASE-T Filters
The CS89712’s 10BASE-T transceiver includes integrated low-pass transmit and receive filters, elimENDEC
Carrier Sense
Carrier
Detector
RXSQL
RX
RX CLK
MAC
RX NRZ
TXCLK
TX NRZ
TEN
Port Select
Decoder
& PLL
RX
MUX
Encoder
TX
MUX
TX
10BASE-T
Transceiver
Clock
Figure 16. ENDEC
52
DS502PP2
CS89712
inating the need for external filters or a
filter/transformer hybrid. On-chip filters are gm/c
implementations of fifth-order Butterworth lowpass filters. Internal tuning circuits keep the gm/c
ratio tightly controlled, even when large temperature, supply, and IC process variations occur. The
nominal 3 dB cutoff frequency of the filters is
16 MHz, and the nominal attenuation at 30 MHz
(3rd harmonic) is -27 dB.
2.28.2 Transmitter
When configured for 10BASE-T operation,
Manchester encoded data from the ENDEC is fed
into the transmitter’s predistortion circuit where
initial wave shaping and preequalization is performed. The output of the predistortion circuit is
LinkOK
(to MAC)
fed into the transmit filter where final wave shaping
occurs and unwanted noise is removed. The signal
then passes to the differential driver where it is amplified and driven out of the TXD+/TXD- pins.
In the absence of transmit packets, the transmitter
generates link pulses in accordance with section
14.2.1.1. of the Ethernet standard. Transmitted link
pulses are positive pulses, one bit time wide, typically generated at a rate of one every 16 ms. The
16 ms timer starts whenever the transmitter completes an End-of-Frame (EOF) sequence. Thus,
there is a link pulse 16 ms after an EOF unless there
is another transmitted packet. Figure 18 diagrams
the operation of the Link Pulse Generator.
10BASE-T Transceiver
Link Pulse
Detector
RX Squelch
RXSQL
RX
ENDEC
TX
TX PreDistortion
RX
Comparator
RX Filters
TX Filters
TX Drivers
RXDRXD+
TXDTXD+
Filter Tuning
Figure 17. 10BASE-T Transceiver
Time
Link
Pulse
Packet
Link
Pulse
Packet
Less Than
16ms
16ms
16ms
Figure 18. Link Pulse Transmission
DS502PP2
53
CS89712
If no link pulses are being received on the receiver,
the 10BASE-T transmitter is internally forced to an
inactive state unless bit DisableLT in the Test Control register is set to one.
2.28.3 Receiver
The 10BASE-T receive section consists of the receive filter, squelch circuit, polarity detection and
correction circuit, and link pulse detector.
2.28.3.1 10BASE-T Squelch Circuit
This circuit determines when valid data is present
on the RXD+/RXD- pair. Incoming signals passing
through the receive filter are tested by the squelch
circuit. Any signal with amplitude less than the
squelch threshold (either positive or negative, depending on polarity) is rejected.
2.28.3.2 Extended Range
The CS89712 supports an Extended Range feature
that reduces the 10BASE-T receive squelch threshold by approximately 6 dB. This allows the
CS89712 to operate with 10BASE-T cables that are
longer than 100 meters (100 meters is the maximum length specified by the Ethernet standard).
The exact additional distance depends on the quality of the cable and the amount of electromagnetic
noise in the surrounding environment. To activate
this feature, the software must set the LoRxSquelch
bit (LineCTL register bit E).
2.28.4 Link Pulse Detection
To prevent disruption of network operation due to
a faulty link segment, the Ethernet port continually
monitors the 10BASE-T receive pair (RXD+/
RXD-) for packets and link pulses. After each
packet or link pulse is received, an internal LinkLoss timer is started. As long as a packet or link
pulse is received before the Link-Loss timer finishes (between 25 and 150 ms), the Ethernet port
maintains normal operation. If no receive activity is
detected, the Ethernet port disables packet transmission to prevent "blind" transmissions onto the
54
network (link pulses are still sent while packet
transmission is disabled). To reactivate transmission, the receiver must detect a single packet (the
packet itself is ignored), or two link pulses separated by more than 2 to 7 ms and no more than 25 to
150 ms (see the Characteristics / Specifications
section for 10BASE-T timing).
The state of the link segment is reported in the
LinkOK bit (LineST register bit 7). If the HC0E bit
(SelfCTL register bit D) is clear, it is also indicated
by the LINKLED output pin. If the link is "good",
the LinkOK bit is set and the LINKLED pin is driven low. If the link is "bad" the LinkOK bit is clear
and the LINKLED pin is high. To disable this feature, the DisableLT bit (TestCTL register bit 7)
must be set. If DisableLT is set, the Ethernet port
will transmit and receive packets independent of
the link segment.
2.28.5 Receive Polarity Detection/Correction
The Ethernet port checks the polarity of the receive
half of the twisted pair cable. If the polarity is correct, the PolarityOK bit (LineST register bit C) is
set. If the polarity is reversed, the PolarityOK bit is
clear. If the PolarityDis bit (LineCTL register bit
C) is clear, the Ethernet port automatically corrects
a reversal. If the PolarityDis bit is set, the port does
not correct a reversal. The PolarityOK bit and the
PolarityDis bit are independent.
To detect a reversed pair, the receiver examines received link pulses and the End-of-Frame (EOF) sequence of incoming packets. If it detects at least
one reversed link pulse and at least four frames in a
row with negative polarity after the EOF, the receive pair is considered reversed. Data received before the correction of the reversal is ignored.
2.28.6 Collision Detection
If half-duplex operation is selected (FDX bit E is
clear), the Ethernet port detects a 10BASE-T collision whenever the receiver and transmitter are active simultaneously. When a collision is present,
DS502PP2
CS89712
the Collision Detection circuit informs the MAC by
asserting the internal Collision signal (see Section
2.26, “Media Access Control Engine” for collision
handling).
2.29 Basic Transmit Operation
Transmit operations occur in the following order
(using interrupts):
1) Software bids for storage of the frame by writing the Transmit Command to the TxCMD Port
and the transmit frame length to the TxLength
Port.
2) Software reads the BusST register to see if the
Rdy4TxNOW bit (Bit 8) is set. To read the
BusST register, the software must first set the
Ethernet Port Pointer at the correct location by
writing 0138h to the Ethernet Port Pointer Port
(offset address 000Ah). It can then read the
BusST register from the Ethernet Port Data
Port (offset address 000Ch). If Rdy4TxNOW is
set, the frame can be written. If clear, the software must wait for Ethernet port buffer memory to become available. If Rdy4TxiE (bit 8 of
BufCFG) is set, an interrupt is generated when
Rdy4Tx (bit 8 of BufEvent) becomes set. If the
TxBidErr bit (BusST register bit 7) is set, the
transmit length is not valid.
3) Once the Ethernet port is ready to accept the
frame, software executes repetitive write instructions (REP OUT) to the Receive/Transmit
Data Port to transfer the entire frame from host
RAM to the Ethernet port’s memory.
For a more detailed description of transmit, see
Section 2.34, “Transmit Operation”.
2.30 Basic Receive Operation
Receive operations occur in the following order (in
this example, interrupts are enabled to signal the
presence of a valid receive frame):
1) A frame is received by the CS89712, triggering
an enabled interrupt.
DS502PP2
2) The software reads the Interrupt Status Queue
Port and is informed of the receive frame.
3) The software reads the frame data by executing
repetitive read instructions from the Receive/Transmit Data Port to transfer the frame
from Ethernet port memory to host RAM. Preceding the frame data are the contents of the
RxStatus register and the RxLength register.
For a more detailed description of receive, see Section 2.32, “Basic Receive Operation”.
2.31 Managing Interrupts & Status Queue
The Interrupt Status Queue (ISQ) is used by the
Ethernet port to communicate Event reports.
Whenever an event occurs that triggers an enabled
interrupt, the Ethernet port sets the appropriate
bit(s) in one of five registers, maps the contents of
that register to the ISQ, and drives the selected interrupt request pin high (if an earlier interrupt is
waiting in the queue, the interrupt request pin will
already be high). When the software services the
interrupt, it must first read the ISQ to learn the nature of the interrupt. It can then process the interrupt (the first read to the ISQ causes the interrupt
request pin to go low.)
Three of the registers mapped to the ISQ are event
registers: RxEvent, TxEvent, and BufEvent. The
other two registers are counter-overflow reports:
RxMISS and TxCOL. There may be more than one
RxEvent report and/or more than one TxEvent report in the ISQ at a time. However, there may be
only one BufEvent report, one RxMISS report and
one TxCOL report in the ISQ at a time.
Event reports stored in the ISQ are read out in the
order of priority, with RxEvent first, followed by
TxEvent, BufEvent, RxMiss, and then TxCOL.
The software only needs to read from one location
to get the interrupt currently at the front of the
queue. It is located at offset address 0008h. Each
time the software reads the ISQ, the bits in the cor-
55
CS89712
responding register are cleared and the next report
in the queue moves to the front.
When the software starts reading the ISQ, it must
read and process all Event reports in the queue. A
read-out of a null word (0000h) indicates that all interrupts have been read.
The ISQ is read as a 16-bit word. The lower six bits
(0 through 5) contain the register number (4, 8, C,
10, or 12). The upper ten bits (6 through F) contain
the register contents. The software must always
read the entire 16-bit word.
The active interrupt pin (INTRQx) is selected via
the Interrupt Number register (Ethernet Port offset
address 22h). As an additional option, all of the interrupt pins can be 3-Stated using the same registers; see Section 3.17 for more details.
An event triggers an interrupt only when the EnableIRQ bit (17) of the Bus Control register is set.
After the CS89712 has generated an interrupt, the
first read of the ISQ makes the INTRQ output pin
go low (inactive). INTRQ remains low until the
null word (0000h) is read from the ISQ, or for
1.6µs, whichever is longer.
2.32 Basic Receive Operation
2.32.1 Overview
Once an incoming packet has passed through the
analog front end and Manchester decoder, it goes
through the following three-step receive process:
1) Pre-Processing
2) Temporary Buffering
3) Transfer to system RAM
As shown in the figure, all receive frames go
through the same pre-processing and temporary
buffering phases, regardless of transfer method
Once a frame has been pre-processed and buffered,
it can be accessed by the software.
2.32.2 Receive Configuration
After each reset, the CS89712 Ethernet port must
be configured for receive operation. This can be
done automatically using an attached EEPROM or
by writing configuration commands to the
CS89712’s internal registers (see Section 2.6,
“Ethernet EEPROM Configurations”). The items
that must be configured include:
•
which types of frames to accept;
•
which receive events cause interrupts; and,
2.32.2.1 Configuring the Physical Interface
Configuring the physical interface consists of enabling the receive logic for serial reception. This is
done via the LineCTL register. Bit 6 enables reception and bit E is used to reduce squelch.
2.32.2.2 Choosing Acceptable Frame Types
The RxCTL register selects which frame types will
be accepted by the Ethernet port. Bits 6 through E
of RxCTL are used for this. Refer to Section 2.32.7,
“Receive Ethernet Port Locations” for a detailed
description of Destination Address filtering, and
Section 3.18.4 on page 119 for RxCTL details.
2.32.2.3
Selecting Interrupt Events
The RxCFG and BufCFG registers are used to determine which receive events will cause interrupts
to the processor. Bits 8, C, D and E of BufCFG are
used for this, and A, B, D and F of BufCFG. See
Section 3.18.2 and Section 3.18.8 for details. Note
that the DA filter must be passsed before there is an
interrupt.
2.32.3 Receive Frame Pre-Processing
The CS89712 pre-processes all receive frames using a four step process:
1) Destination Address filtering;
2) Early Interrupt Generation;
3) Acceptance filtering; and,
56
DS502PP2
CS89712
An enabled interrupt occurs.
The selected interrupt
request pin is driven high
(active) if not already high.
The host reads the ISQ.
The selected interrupt
request pin is driven low.
EXIT.
Interrupts
re-enabled.
(Interrupts
will be
disabled
for at least
1.6 us.)
Yes
ISQ = 0000h?
No
Which
Event
report
type?
RxEvent
Process applicable
RxEvent bits: Extradata,
Runt, CRCerror, RxOK.
TxEvent
Process applicable
TxEvent bits: 16coll, Jabber,
Out-of-window, TxOK.
BufEvent
Process applicable BufEvent
bits: RxDest, Rx128, RxMiss,
TxUnderrun, Rdy4Tx,
RxDMAFrame, SWint.
RxMISS
TxCOL
Process RxMISS counter.
Process TxCOL counter.
None of the above
Service
Default
Figure 19. Interrupt Status Queue
DS502PP2
57
CS89712
4) Normal Interrupt Generation.
Receive Frame
Figure 20 diagrams frame pre-processing.
Destination
Address Filter
2.32.3.1 Destination Address Filtering
Check:
- PromiscuousA?
- IAHashA?
- MulticastA?
- IndividualA?
- BroadcastA?
All incoming frames are passed through the Destination Address filter (DA filter). If the frame’s DA
passes the DA filter, the frame is passed on for further pre-processing. If it fails the DA filter, the
frame is discarded. See Section 2.32.7, “Receive
Ethernet Port Locations” for a more detailed description of DA filtering.
Pass
DA Filter?
No
Discard Frame
2.32.3.2 Early Interrupt Generation
Yes
The Ethernet port supports the following two early
interrupts for frame reception.
•
RxDest
The RxDest bit (bit F of BufEvent register) is
set as soon as the Destination Address (DA) of
the incoming frame passes the DA filter. If the
RxDestiE bit (BufCFG register bit F) is set, the
CS89712 generates a corresponding interrupt.
Once RxDest is set, the software is allowed to
read the incoming frame's DA (the first 6 bytes
of the frame).
•
Rx128
The Rx128 bit (BufEvent register bit B) is set
as soon as the first 128 bytes of the incoming
frame have been received. If the Rx128iE bit
(BufCFG register bit B) is set, the CS89712
generates a corresponding interrupt. Once the
Rx128 bit is set, the RxDest bit is cleared and
the software is allowed to read the first 128
bytes of the incoming frame. The Rx128 bit is
cleared by the software reading the BufEvent
register (either directly or through the Interrupt
Status Queue) or by the CS89712 detecting the
incoming frame’s End-of-Frame (EOF) sequence.
Like all Event bits, RxDest and Rx128 are set by
the whenever the appropriate event occurs. Unlike
other Event bits, RxDest and Rx128 may be cleared
58
Generate Early
Interrupts if Enabled
(see next figure)
Acceptance Filter
Check:
- RxOKA?
- ExtradataA?
- RuntA?
- CRCerrorA?
Yes
Pass
Accept.
Filter?
No
Status of receive
frame reported in
RxEvent register,
frame discarded.
Status of receive
frame reported in
RxEvent register,
frame accepted
into on-chip RAM
Generate Interrupts
Check:
- RxOKiE?
- ExtradataiE?
- CRCerroriE?
- RuntiE?
Pre-Processing
Complete
Figure 20. Receive Frame Pre-Processing
DS502PP2
CS89712
by the Ethernet port without software intervention.
All other event bits are cleared only by the software
reading the appropriate event register, either directly or through the Interrupt Status Queue (ISQ).
(RxDest and Rx128 can also be cleared by the software reading the BufEvent register, either directly
or through the Interrupt Status Queue).
2.32.3.3 Acceptance Filtering
The third step of pre-processing is to determine
whether or not to accept the frame by comparing
the frame with the criteria programmed into the RxCTL register. If the receive frame passes the Acceptance filter, the frame is buffered on chip. If the
frame fails the Acceptance filter, it is discarded.
The results of the Acceptance filter are reported in
the RxEvent register.
2.32.3.4 Normal Interrupt Generation
The final step of pre-processing is to generate any
enabled interrupts that are triggered by the incoming frame. Interrupt generation occurs when the entire frame has been buffered (up to the first
1518 bytes). For more information about interrupt
generation, see Section 2.31, “Managing Interrupts & Status Queue”.
2.32.4 Buffering Held Receive Frames
If space is available, an incoming frame will be
temporarily stored in on-chip RAM, where it
awaits processing by the software. Although this
receive frame now occupies on-chip memory, the
Ethernet port does not commit the memory space to
it until one of the following two conditions is true:
come set, and the software has learned about
the receive frame by reading the BufEvent register, either directly or through the ISQ.
When the CS89712 commits buffer space to a particular held receive frame (termed a committed received frame), no data from subsequent frames can
be written to that buffer space until the frame is
freed from commitment. (The committed received
frame may or may not have been received error
free.)
A received frame is freed from commitment by any
one of the following conditions:
1) The software reads the entire frame sequentially in the order that it was received (first byte in,
first byte out).
or:
2) The software reads part or none of the frame,
and then issues a Skip command by setting the
Skip_1 bit (RxCFG register bit 6).
or:
3) The software reads part of the frame and then
reads the RxEvent register, either directly or
through the ISQ, and learns of another receive
frame. This condition is called an "implied
Skip". Ensure that the software does not do
“implied skips.”
Both early interrupts are disabled whenever there is
a committed receive frame waiting to be processed
by the software.
There are three possible ways that the software can
learn the status of a particular frame. It can:
1) The entire frame has been received and the software has learned about the frame by reading the
RxEvent register, either directly or through the
ISQ.
1) Read the Interrupt Status Queue;
or:
2.32.5 Receive Frame Visibility
2) The frame has been partially received, causing
either the RxDest bit (BufEvent register bit F)
or the Rx128 bit (BufEvent register bit B) to be-
Only one receive frame is visible to the software at
a time. The receive frame's status can be read from
DS502PP2
2) Read the RxEvent register directly ; or
3) Read the RxStatus register.
59
CS89712
the RxStatus register, and its length can be read
from the RxLength register.
2.32.6
Receive Frame Byte Counter
The receive frame byte counter describes the number of bytes received for the current frame. The
counter is incremented in real time as bytes are received from the Ethernet. The byte counter can be
used by the driver to determine how many bytes are
available for reading out of the Ethernet port. Maximum Ethernet throughput can be achieved by dedicating the CPU to reading this counter, and using
the count to read the frame out of the Ethernet port
at the same time it is being received by the
CS89712 from the Ethernet (parallel frame-reception and frame-read-out tasks).
Following an RxDest or Rx128 interrupt the register contains the number of bytes which are available to be read by the CPU. When the end of frame
is reached, the count contains the final count value
for the frame, including the allowance for the BufferCRC option. When this final count is read by the
CPU the count register is set to zero. Therefore to
read a complete frame using the byte count register,
the register can be read and the data moved until a
count of zero is detected. Then the RxEvent register can be read to determine the final frame status.
The sequence is as follows:
1) At the start of a frame, the byte counter matches
the incoming character counter. The byte
counter will have an even value prior to the end
of the frame.
2) At the end of the frame, the final count, including the allowance for the CRC (if the BufferCRC option is enabled), is held until the byte
counter is read.
3) When a read of the byte counter returns a count
of zero, the previous count was the final count.
The count may now have an odd value.
4) RxEvent should be read to obtain a final status
60
of the frame, followed by a Skip command to
complete the operation.
Note that all RxEvents should be processed before
using the byte counter. The byte counter should be
used following a BufEvent when RxDest or Rx128
interrupts are enabled.
2.32.7 Receive Ethernet Port Locations
The receive status/length/frame locations are read
through repetitive reads from one Ethernet port at
the I/O base address.
Random access is not needed. However, the first
118 bytes of the receive frame can be accessed randomly if word reads, on even word boundaries, are
used. Beyond 118 bytes, the memory reads must be
sequential. Byte reads, or reads on odd-word
boundaries, can be performed only in sequential
read mode.
The RxStatus word reports the status of the current
received frame. RxEvent has the same contents as
the RxStatus register, except RxEvent is cleared
when read.
The RxLength (receive length) word is the length,
in bytes, of the data to be transferred to the host
RAM. The register describes the length from the
start of Destination Address to the end of CRC, assuming that CRC has been selected (via RxCFG
register bit BufferCRC). If CRC has not been selected, then the length does not include the CRC,
and the CRC is not present in the receive buffer.
After the RxLength has been read, the receive
frame can be read. When some portion of the frame
is read, the entire frame should be read before reading the RxEvent register either directly or through
the ISQ register. Reading the RxEvent register signals to the Ethernet port that the software is finished with the current frame, and wants to start
processing the next frame. In this case, the current
frame will no longer be accessible. The current
frame will also become inaccessible if a Skip com-
DS502PP2
CS89712
mand is issued, or if the entire frame has been read.
See Section 2.32, “Basic Receive Operation”.
sults of the DA filter for a given receive frame. See
Section 3.18.4 on page 119 for RxCTL details.
2.33 Receive Frame Address Filtering
The IAHashA, MulticastA, IndividualA, and
BroadcastA bits are used independently. As a result, many DA filter combinations are possible. For
example, if MulticastA and IndividualA are set,
then all frames that are either Multicast or Individual Address frames are accepted. The PromiscuousA bit, when set, overrides the other four DA
bits, and allows all valid frames to be accepted.
Table 29 summarizes the configuration options
available for DA filtering.
The Ethernet port is equipped with a Destination
Address (DA) filter used to determine which receive frames will be accepted. The DA filter can be
configured to accept the following frame types:
2.33.1 Individual Address Frames
For all Individual Address frames, the first bit of
the DA is a "0" (DA[0] = 0), indicating that the address is a Physical Address. The address filter accepts Individual Address frames whose DA
matches the Individual Address or whose hash-filtered DA matches one of the bits programmed into
the Logical Address Filter (the hash filter is described later in this section).
2.33.2 Multicast Frames
For Multicast Frames, the first bit of the DA is a "1"
(DA[0] = 1), indicating that the frame is a Logical
Address. The address filter accepts Multicast
frames whose hash-filtered DA matches one of the
bits programmed into the Logical Address Filter
(the hash filter is described later is this section). As
shown in Table 28, Broadcast Frames can be accepted as Multicast frames under a very specific set
of conditions.
2.33.3 Broadcast Frames
Frames with DA equal to FFFF.FFFF.FFFFh are
broadcast frames. In addition, the CS89712 can be
configured for Promiscuous Mode, in which case it
will accept all receive frames, irrespective of DA.
2.33.4 Destination Address Filter
The DA filter is configured by five DA filter bits in
the RxCTL register: IAHashA, PromiscuousA,
MulticastA, IndividualA, and BroadcastA. Four of
these bits are associated with four status bits in the
RxEvent register: IAHash, Hashed, IndividualAdr,
and Broadcast. The RxEvent register reports the reDS502PP2
It may become necessary for the software to change
the Destination Address (DA) filter criteria without
resetting the Ethernet port. This can be done as follows:
1) Clear SerRxON (LineCTL register bit 6) to prevent any additional receive frames while the filter is being changed.
2) Modify the DA filter bits (B, A, 9, 7, and 6) in
the RxCTL register. Modify the Logical Address Filter, if necessary.
3) Set SerRxON to re-enable the receiver.
Because the receiver has been disabled, the
CS89712 will ignore frames while the software is
changing the DA filter.
2.33.5 Hash Filter
The hash filter is used to help determine which
Multicast frames and which Individual Address
frames should be accepted by the CS89712.
2.33.5.1 Hash Filter Operation
See Figure 21. The DA of the incoming frame is
passed through the CRC logic, generating a 32-bit
CRC value. The six most-significant bits of the
CRC are latched into the 6-bit hash register (HR).
The contents of the HR are passed through a 6-to64-bit decoder, asserting one of the decoder’s outputs. The asserted output is compared with a corresponding bit in the 64-bit Logical Address Filter,
61
CS89712
Address
Erred
Type of Frame?
Received
Frame
Individual
Address
Multicast
Address
Broadcast
Address
Passes
Hash
Filter?
Contents of RxEvent
Bits F-A
Bit 9
Hashed
Hash Table Index
Bit 8
RxOK
Bit 6
IAHash
no
yes
1
1
1
no
no
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
1
0
yes
don’t care
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
0
0
no
yes
1
1
0
no
no
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
1
0
yes
don’t care
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
0
0
no
yes
(Note 1)
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
1
1
0
no
yes
(Note 2)
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
1
0
no
no
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
1
0
yes
don’t care
ExtraData
Runt
CRC
Error
Broadcast
Individual
Adr
0
0
0
Hash table index
(actual value X00010)
Notes: 1. Broadcast frames are accepted as Multicast frames if and only if all the following conditions are met
simultaneously:
a) the Logical Address Filter is programmed as: (MSB) 0000 8000 0000 0000h (LSB). Note that this
LAF value corresponds to a Multicast Addresses of both all 1s and 03-00-00-00-00-01.
b) the Rx Control Register (register 5) is programmed to accept IndividualA, MulticastA, RxOK-only,
and the following address filters were enabled: IAHashA and BroadcastA.
2. NOT (Note 1).
Table 28. Contents of RxEvent Upon Various Conditions
IAHashA
Promiscuous
A
MulticastA
IndividualA
BroadcastA
Frames Accepted
0
0
0
1
0
Individual Address frames with
DA matching the IA at Ethernet
Port offset address 0158h
1
0
0
0
0
Individual Address frames with
DA that pass the hash filter
(DA[0] must be “0”)
0
0
1
0
0
Multicast frames with DA that
pass the hash filter (DA[0] must
be “1”)
0
0
0
0
1
Broadcast frames
X
1
X
X
X
All frames
Table 29. Destination Address Filtering Options
62
DS502PP2
CS89712
located at Ethernet Port offset address 0150h. If the
decoder output and the Logical Address Filter bit
match, the frame passes the hash filter and the
Hashed bit (RxEvent register bit 9) is set. If the two
do not match, the frame fails the filter and the
Hashed bit is clear.
Whenever the hash filter is passed by a "good"
frame, the RxOK bit (RxEvent register bit 8) is set
and the bits in the HR are mapped to the Hash Table
Index bits (RxEvent register, bits A through F).
2.33.6
Broadcast Frame Hashing Exception
Table 28 describes in detail the content of the RxEvent register for each output of the hash and address filters, and describes an exception to normal
processing. That exception can occur when the
hash-filter Broadcast address matches a bit in the
Logical Address Filter. To properly account for this
exception, the software driver should use the following test to determine if the RxEvent register
contains a normal RxEvent (meaning bits E-A are
used for Extra data, Runt, CRC Error, Broadcast
and IndividualAdr) or a hash-table RxEvent (meaning bits F-A contain the Hash Table Index).
If bit Hashed =0, or bit RxOK=0, or (bits F-A = 02h
and the destination address is all ones) then RxEvent contains a normal RxEvent, else RxEvent
contained a hash RxEvent.
2.34 Transmit Operation
2.34.1 Overview
Packet transmission occurs in two phases. In the
first phase, the Ethernet frame is moved into the
Ethernet port’s buffer memory. This phase begins
with the software issuing a Transmit Command.
This informs the CS89712 that a frame is to be
transmitted and tells the chip when (i.e. after 5,
381, or 1021 bytes have been transferred or after
the full frame has been transferred to the CS89712)
and how the frame should be sent (i.e. with or without CRC, with or without pad bits, etc.). The software follows the Transmit Command with the
Transmit Length, indicating how much buffer
space is required. When buffer space is available,
the software writes the Ethernet frame into the
Ethernet port’s internal memory.
In the second phase of transmission, the Ethernet
port converts the frame into an Ethernet packet then
transmits it onto the network. The second phase begins with the Ethernet port transmitting the preamble and Start-of-Frame delimiter as soon as the
proper number of bytes has been transferred into its
transmit buffer (5, 381, 1021 bytes or full frame,
depending on configuration). The preamble and
Start-of-Frame delimiter are followed by the data
transferred into the on-chip buffer by the software
(MSB)
Destination Address (DA)
from incoming frame
32-bit CRC value
CRC
Logic
(LSB)
6-bit Hash Register (HR)
[Hash Table Index]
6-to-64 decoder
to
Hashed
bit
1
64
64-input
OR gate
64-bit Logical Address Filter (LAF)
Written into PacketPage base + 150h
Figure 21. Hash Filter Operation
DS502PP2
63
CS89712
(Destination Address, Source Address, Length
field and LLC data). If the frame is less than 64
bytes, including CRC, the CS89712 adds pad bits if
configured to do so. Finally, the CS89712 appends
the proper 32-bit CRC value.
If the LineCTL register bits are changed after initialization, the ModBackoffE bit and any receive
related bit (LoRxSquelch, SerRxON) may be
changed at any time.
2.34.2 Transmit Configuration
Whenever the software issues a Transmit Request
command, it must indicate whether or not the Cyclic Redundancy Check (CRC) value should be appended to the transmit frame, and whether or not
pad bits should be added (if needed). Bits C and D
of TxCMD are used, refer to Table 3.18.7 on
page 122.
After each reset, the Ethernet port must be configured for transmit operation. This can be done automatically using an attached EEPROM, or by
writing configuration commands to the Ethernet
port’s internal registers (see Section 2.6, “Ethernet
EEPROM Configurations”). The items that must
be configured include which physical interface to
use and which transmit events cause interrupts.
2.34.2.1 Configuring the Physical Interface
Configuring the Physical Interface is accomplished
via the LineCTL register. Bit 6 enables reception
and bit 9 enables transmission, while bits B and D
control backoff and deferral. See Section 3.18.12
on page 127 for LineCTL details.
Note that the CS89712 transmits in 10BASE-T
mode when no link pulses are being received only
if bit DisableLT is set in the Test Control register.
2.34.4 Enabling CRC Generation/Padding
2.34.5 Individual Packet Transmission
Whenever the software has a packet to transmit, it
must issue a Transmit Request to the Ethernet port
consisting of the following three operations in the
exact order shown:
1) The software must write a Transmit Command
to the TxCMD register. The contents of the TxCMD register may be read back from the TxCMD register.
2) The software must write the frame’s length to
the TxLength register.
2.34.2.2 Selecting Interrupt Events
3) Software must read the BusST register.
The TxCFG and BufCFG registers are used to determine which transmit events will cause interrupts. TxCFG [B:8] and F, and BufCFG [9:8] and
C are used. Refer to Section 3.18.5 and
Section 3.18.8 for details.
The information written to the TxCMD register
tells the Ethernet port how to transmit the next
frame. Appropriate bits in TxCMD are 6:9, C and
D. Refer to Table 3.19 on page 133.
2.34.3
Changing the Configuration
When software configures these registers it does
not need to change them for subsequent packet
transmissions. The TxCFG or BufCFG register bits
may be changed at any time. The effects of the
change are noticed immediately. Any changes in
the Interrupt Enable (iE) bits may affect the packet
currently being transmitted.
64
For each individual packet transmission, software
must issue a complete Transmit Request. Furthermore, the software must write to the TxCMD register before each packet transmission, even if the
contents of the TxCMD register do not change.
2.34.6 Transmit in Poll Mode
In poll mode, Rdy4TxiE bit (BufCFG register bit 8)
must be clear (Interrupt Disabled). The transmit operation occurs in the following order:
DS502PP2
CS89712
1) Software bids for frame storage by writing the
Transmit Command to the TxCMD register.
2) Software writes the transmit frame length to the
TxLength register. If the transmit length is erroneous, the command is discarded and the TxBidErr bit (BusST register bit 7) is set.
3) The BusST register is read. The software must
first set the Ethernet Port Pointer at the correct
location by writing 0138h to the Ethernet Port
Pointer Port. Software can then read the BusST
register from the Ethernet Port Data Port.
4) After the read, Rdy4TxNOW (bit 8) is checked.
If set, the frame can be written. If clear, the software must continue reading the BusST register
and checking Rdy4TxNOW until set.
When the CS89712 is ready to accept the frame,
software transfers the frame from host RAM to
Ethernet port memory Receive/Transmit Data Port.
2.34.7 Transmit in Interrupt Mode
In interrupt mode, Rdy4TxiE bit (BufCFG register
bit 8) must be set for transmit operation. Transmit
operation occurs in the following order:
1) The software bids for frame storage by writing
the Transmit Command to the TxCMD register.
2) The software writes the transmit frame length
to the TxLength register. If the transmit length
is erroneous, the command is discarded and the
TxBidErr, bit 7, in BusST register is set.
3) The BusST register is read. If the Rdy4TxNOW
bit is set, the frame can be written to Ethernet
port memory. If Rdy4TxNOW is clear, software will have to wait for the Ethernet port
buffer memory to become available at which
time an interrupt is generated. On interrupt, the
interrupt service routine reads ISQ register and
checks the Rdy4Tx bit (bit 8). If Rdy4Tx is
clear then the software waits for the next interrupt. If Rdy4Tx is set, then the Ethernet port is
ready to accept the frame.
DS502PP2
4) When the Ethernet port is ready to accept the
frame, the software transfers the entire frame
from host memory to Ethernet port memory to
Receive/Transmit Data Port.
2.34.8 Completing Transmission
When the CS89712 successfully completes transmitting a frame, it sets the TxOK bit (TxEvent register bit 8). If the TxOKiE bit (TxCFG register bit
8) is set, an interrupt is generated.
2.34.9 Rdy4TxNOW vs. Rdy4Tx
The Rdy4TxNOW bit (BusST register bit 8) is used
to indicate the Ethernet port is ready to accept a
frame for transmission. This bit is used during the
Transmit Request process or after the Transmit Request process to signal the software that space has
become available when interrupts are not being
used (i.e. Rdy4TxiE, bit 8 of Register B, is not set).
Also, the Rdy4Tx bit is used with interrupts and requires the Rdy4TxiE bit be set.
2.34.10 Committing Buffer Space to a Frame
When the software issues a transmit request, the
Ethernet port checks the length of the transmit
frame to see if there is sufficient on-chip buffer
space. If there is, the Ethernet port sets the
Rdy4TxNOW bit. If not, and the Rdy4TxiE bit is
set, the Ethernet port waits for buffer space to free
up and then sets the Rdy4Tx bit.
Even though transmit buffer space may be available, the Ethernet port does not commit buffer
space to a transmit frame until all of the following
are true:
1) The software must issues a Transmit Request;
2) The Transmit Request must be successful; and,
3) Either the software reads that the Rdy4TxNOW
bit (BusST register bit 8) is set, or the software
reads that the Rdy4Tx bit (BufEvent register bit
8) is set.
65
CS89712
If the CS89712 commits buffer space to a particular
transmit frame, it will not allow subsequent frames
to be written to that buffer space as long as the
transmit frame is committed.
After buffer space is committed, the frame is subsequently transmitted unless any of the following
occur:
1) The software completely writes the frame data,
but transmission failed on the Ethernet line.
There are three such failures, and these are indicated by three bits in the TxEvent register:
16coll, Jabber, or Out-of-Window.
or:
2) The software aborts the transmission by setting
the Force (TxCMD register bit 8) bit. In this
case, the committed transmit frame, as well as
any yet-to-be-transmitted frames queued in the
on-chip memory, are cleared and not transmitted. The software should make TxLength = 0
when using the Force bit.
or:
TxCMD register
3) There is a transmit under-run while the TxUnderrun bit (BufEvent register bit 9) is set.
Successful transmission is indicated when the
TxOK bit (TxEvent register bit 8) is set.
2.34.11 Transmit Frame Length
The length of the frame transmitted is determined
by the value written into the TxLength register
during the Transmit Request. The length of the
transmit frame may be modified by the configuration of the TxPadDis bit (TxCMD register bit D)
and the InhibitCRC bit (TxCMD register bit C).
Table 30 defines how these bits affect the length of
the transmit frame, and details which frames will
be sent.
2.35 Full Duplex Considerations
The driver should not bid to transmit a long frame
(i.e., a frame greater than 118 bytes) if the prior
transmit frame is still being transmitted. The end of
the transmission of this prior frame is indicated by
a TxOK bit being set in the TxEvent register.
Software specified transmit length at 0146h (in bytes)
TxPadDis
(Bit D)
InhibitCRC
(Bit C)
3 < TxLength
< 60
60 < TxLength
< 1514
1514 < TxLength
< 1518
TxLength
> 1518
0
0
Pad to 60 and add
CRC
Send frame and add
CRC [Normal Mode]
Will not send
Will not send
0
1
Pad to 60 and send
without CRC
Send frame without
CRC
Send frame
without CRC
Will not send
1
0
Send without pads,
and add CRC
Send frame and add
CRC
Will not send
Will not send
1
1
Send without pads
and without CRC
Send frame without
CRC
Send frame
without CRC
Will not send
Notes: 1. If the TxPadDis bit is clear and InhibitCRC is set and the CS89712 is commanded to send a frame of
length less than 60 bytes, the CS89712 pads.
2. The CS89712 will not send a frame with TxLength less than 3 bytes.
Table 30. Transmit Frame Length
66
DS502PP2
CS89712
2.36 Auto-Negotiation Considerations
The original IEEE 802.3 specification requires the
MAC to wait until 4 valid link-pulses are received
before asserting Link-OK. Any time an invalid
link-pulse is received, the count is restarted. When
auto-negotiation occurs, a transmitter sends FLP
(Fast Link Pulse) bursts instead of the original
IEEE 802.3 NLP (Normal Link Pulses).
If the hub is attempting to auto-negotiate with the
CS89712, the CS89712 will never get more than 1
DS502PP2
"valid" link pulse (valid NLP). This is not a problem if the CS89712 is already sending link-pulses,
because when the hub receives NLPs from the
CS89712, the hub is required to stop sending FLPs
and start sending NLPs. The NLP transmitted by
the hub will put the CS89712 into Link-OK.
However, if the CS89712 is in Auto-Switch mode,
the CS89712 will never send any link-pulses, and
the hub will never change from sending FLPs to
sending NLPs.
67
CS89712
3. REGISTER SET
The 89712 contains multiple register ranges.
An 8 kbyte segment of memory in the range
0x8000.0000 to 0x8000.3FFF is for registers that
control non-Ethernet functions. Section 3.1 gives
an overview of these while Sections 3.3 through
3.16 provide register bit details.
Ethernet port registers are accessed through two
separate ranges: a 16 byte window of eight registers
and a 4 Kbyte page of registers. Section 3.2 explains Ethernet Port register access, and Sections
3.17 to 3.20 give bit details.
3.1 Non-Ethernet Registers
Table 31 shows the internal non-Ethernet registers
of the CS89712 when the CPU is configured to a
little endian memory system. Table 32 shows the
differences that occur when the CPU is configured
to a big endian memory system for byte-wide access to Ports A, B, and D. All the internal registers
are inherently little endian (i.e., the least significant
byte is attached to bits 7 to 0 of the data bus).
Hence, the system Endianness affects the addresses
required for byte accesses to the internal registers,
resulting in a reversal of the byte address required
to read/write a particular byte within a register.
There is no effect on the register addresses for word
accesses. Bits A[1:0] of the internal address bus are
only decoded for Ports A, B, and D (to allow
read/write to individual ports). For all other registers, bits A[1:0] are not decoded, so that byte reads
will return the whole register contents onto the
CS89712’s internal bus, from where the appropriate byte (according to the endianness) will be read.
To avoid the additional complexity, it is preferable
to perform all internal register accesses as word operations, except for ports A to D which are explic-
68
itly designed to operate with byte accesses, as well
as with word accesses.
Writes to bits that are not explicitly defined in the
internal area are legal and will have no effect.
Reads from bits not explicitly defined in the internal area are legal but will read undefined values.
All the internal addresses should only be accessed
as 32-bit words and are always on a word boundary, except for the PIO port registers, which can be
accessed as bytes. Address bits in the range A[0:5]
are not decoded (except for Ports A–D), this means
each internal register is valid for 64 bytes (i.e., the
SYSFLG1 register appears at locations
0x8000.0140 to 0x8000.017C). There are some
gaps in the register map but registers located next
to a gap are still only decoded for 64 bytes.
The GPIO port registers are byte-wide and can be
accessed as a word but not as a half-word. These
registers additionally decode A[1:0].
Note: All byte-wide registers should be accessed as
words (except Port A to Port D registers, which are
designed to work in both word and byte modes).
All register bit alignment starts from the LSB of the
register (i.e., they are all right shift justified).
The registers which interact with the 32 kHz clock or
which could change during readback (i.e., RTC data
registers, SYSFLG1 register (lower 6-bits only), the
TC1D and TC2D data registers, port registers, and
interrupt status registers), should be read twice and
compared to ensure that a stable value has been read.
All internal registers are reset to zero by a system
reset (i.e., nPOR, nURESET, or nPWRFL signals
becoming active), except for the DRAM refresh period register (DPFPR), the Real-Time Clock data
register (RTCDR), and the match register (RTCMR), which are only reset by nPOR becoming active. This ensures that the DRAM contents and
system time are preserved through a user reset or
power fail condition.
DS502PP2
CS89712
Address
Name
Default
0x8000.0000
PADR
0
RW
8
Port A data register.
0x8000.0001
PBDR
0
RW
8
Port B data register.
0x8000.0002
—
—
8
Reserved.
0x8000.0003
PDDR
0
RW
8
Port D data register.
0x8000.0040
PADDR
0
RW
8
Port A data direction register.
0x8000.0041
PBDDR
0
RW
8
Port B data direction register.
0x8000.0042
—
—
8
Reserved.
0x8000.0043
PDDDR
0
RW
8
Port D data direction register.
0x8000.0080
PEDR
0
RW
3
Port E data register.
0x8000.00C0
PEDDR
0
RW
3
Port E data direction register.
0x8000.0100
SYSCON1
0
RW
32
System control register 1.
0x8000.0140
SYSFLG1
0
RD
32
System status flags register 1.
0x8000.0180
MEMCFG1
0
RW
32
Expansion memory configuration register 1.
0x8000.01C0
MEMCFG2
0
RW
32
Expansion memory configuration register 2.
0
RW
32
Reserved.
0x8000.0200
RD/WR Size
Comments
0x8000.0240
INTSR1
0
RD
32
Interrupt status register 1.
0x8000.0280
INTMR1
0
RW
32
Interrupt mask register 1.
0x8000.02C0
LCDCON
0
RW
32
LCD control register.
0x8000.0300
TC1D
0
RW
16
Read / Write register sets and reads data to TC1.
0x8000.0340
TC2D
0
RW
16
Read / Write register sets and reads data to TC2.
0x8000.0380
RTCDR
—
RW
32
Real Time Clock data register.
0x8000.03C0
RTCMR
—
RW
32
Real Time Clock match register.
0x8000.0400
PMPCON
0
RW
12
PWM pump control register.
0x8000.0440
CODR
0
RW
8
CODEC data I/O register.
0x8000.0480
UARTDR1
0
RW
16
UART1 FIFO data register.
0x8000.04C0
UBLCR1
0
RW
32
UART1 bit rate and line control register.
0x8000.0500
SYNCIO
0
RW
32
Synchronous serial I/O data register for master
only SSI.
0x8000.0540
PALLSW
0
RW
32
Least significant 32-bit word of LCD palette register.
0x8000.0580
PALMSW
0
RW
32
Most significant 32-bit word of LCD palette register.
0x8000.05C0
STFCLR
—
WR
—
Write to clear all start up reason flags.
0x8000.0600
BLEOI
—
WR
—
Write to clear battery low interrupt.
0x8000.0640
MCEOI
—
WR
—
Write to clear media changed interrupt.
0x8000.0680
TEOI
—
WR
—
Write to clear tick and watchdog interrupt.
0x8000.06C0
TC1EOI
—
WR
—
Write to clear TC1 interrupt.
0x8000.0700
TC2EOI
—
WR
—
Write to clear TC2 interrupt.
0x8000.0740
RTCEOI
—
WR
—
Write to clear RTC match interrupt.
Table 31. CS89712 Internal Registers (Little Endian Mode)
DS502PP2
69
CS89712
Address
Name
Default
0x8000.0780
UMSEOI
—
WR
—
Write to clear UART modem status changed interrupt.
0x8000.07C0
COEOI
—
WR
—
Write to clear CODEC sound interrupt.
0x8000.0800
HALT
—
WR
—
Write to enter the Idle State.
0x8000.0840
STDBY
—
WR
—
Write to enter the Standby State.
0x8000.0880–
0x8000.0FFF
Reserved
0x8000.1000
FBADDR
0xC
RW
4
LCD frame buffer start address.
0x8000.1100
SYSCON2
0
RW
16
System control register 2.
0x8000.1140
SYSFLG2
0
RD
24
System status register 2.
0x8000.1240
INTSR2
0
RD
16
Interrupt status register 2.
0x8000.1280
INTMR2
0
RW
16
Interrupt mask register 2.
0x8000.12C0–
0x8000.147F
Reserved
0x8000.1480
UARTDR2
0
RW
16
UART2 Data register.
0x8000.14C0
UBLCR2
0
RW
32
UART2 bit rate and line control register.
0x8000.1500
SS2DR
0
RW
16
Master / slave SSI2 data register.
0x8000.1600
SRXEOF
—
WR
—
Write to clear RX FIFO overflow flag.
0x8000.16C0
SS2POP
—
WR
—
Write to pop SSI2 residual byte into RX FIFO.
0x8000.1700
KBDEOI
—
WR
—
Write to clear keyboard interrupt.
0x8000.1800
Reserved
—
WR
—
Do not write to this location. A write will cause the
processor to go into an unsupported power state.
0x8000.1840–
0x8000.1FFF
Reserved
—
0x8000.2000
DAIR
0
RW
32
DAI control register.
0x8000.2040
DAIR0
0
RW
32
DAI data register 0.
0x8000.2080
DAIDR1
0
RW
32
DAI data register 1.
0x8000.20C0
DAIDR2
0
WR
21
DAI data register 2.
0x8000.2100
DAISR
0
RW
32
DAI status register.
0x8000.2200
SYSCON3
0
RW
16
System control register 3.
0x8000.2240
INTSR3
0
RD
32
Interrupt status register 3.
0x8000.2280
INTMR3
0
RW
8
Interrupt mask register 3.
0
RW
7
LED Flash register.
0x8000.22C0
LEDFLSH
RD/WR Size
Comments
Write will have no effect, read is undefined.
Write will have no effect, read is undefined. .
Write will have no effect, read is undefined.
Table 31. CS89712 Internal Registers (Little Endian Mode) (Continued)
Big Endian Mode
Name
Default
RD/WR
Size
0x8000.0003
PADR
0
RW
8
Comments
Port A Data register
Table 32. CS89712 Internal Registers (Big Endian Mode)
70
DS502PP2
CS89712
Big Endian Mode
Name
Default
RD/WR
Size
Comments
0x8000.0002
PBDR
0
RW
8
Port B Data register
0x8000.0001
—
—
8
Reserved
0x8000.0000
PDDR
0
RW
8
Port D Data register
0x8000.0043
PADDR
0
RW
8
Port A data Direction register
0x8000.0042
PBDDR
0
RW
8
Port B Data Direction register
0x8000.0041
—
—
8
Reserved
0x8000.0040
PDDDR
0
RW
8
Port D Data Direction register
0x8000.0083
PEDR
0
RW
3
Port E Data Register
0X8000.00C3
PEDDR
0
RW
3
Port E Data Direction register
Table 32. CS89712 Internal Registers (Big Endian Mode)
1. The following register descriptions refer to Little Endian Mode Only.
3.2 Accessing Ethernet Port Registers
Registers for the Ethernet port are accessed through
two memory ranges; first, a 16-byte window of
eight 16-bit registers (shown in Figure 33) located
at address 0x2000.0300; and additional registers in
a 4 Kbyte internal memory page listed in Figure 36.
The registers at 0x2000.0300 are always immediately accessable, however registers mapped into
the 4 Kbyte page must be accessed through an index using the Ethernet Port pointer and Ethernet
Data Ports.
This is done by writing the offset of the target register to the Ethernet Port Pointer. For example, the
EEPROM data register has an offset of 0042h. The
contents of the target register are then mapped into
the Ethernet Data Port.
If the software needs to access a sequential block of
registers, the MSB of the Ethernet Port address of
the first word to be accessed should be set to "1".
The Ethernet Port Pointer will then move to the
next word location automatically, eliminating the
need to setup the Ethernet Port Pointer between
successive accesses (see Figure 22).
Memory Location
Type
Description
0x2000.0300
Read/Write
Receive/Transmit Data (Port 0)
0x2000.0302
Read/Write
Receive/Transmit Data (Port 1)
0x2000.0304
Write-only
TxCMD (Transmit Command)
0x2000.0306
Write-only
TxLength (Transmit Length)
0x2000.0308
Read-only
Interrupt Status Queue
0x2000.030A
Read/Write
Ethernet Port Pointer
0x2000.030C
Read/Write
Ethernet Port Data (Port 0)
0x2000.030E
Read/Write
Ethernet Port Data (Port 1)
Table 33. Ethernet Port Register Window
DS502PP2
71
CS89712
3.2.1
Ethernet Port Register Window
This section refers to the eight 2-byte registers residing in the 16-byte window at 0x2000.3000.
These registers are always immediately available.
3.2.1.1
Receive/Transmit Data Ports 0 & 1
These two ports are used when transferring transmitting/receving data to/from the CS89712. Port 0
is used for 16-bit operations and Ports 0 and 1 are
for 32-bit operations (lower-order word in Port 0).
3.2.1.2
TxCMD Port
Software writes the Transmit Command (TxCMD)
to this port at the start of each transmit operation.
The Transmit Command indicates that the software
has a frame to be transmitted, as well as how that
frame should be transmitted. See Section 3.2.3,
“Ethernet Status/Control Registers” for more information.
3.2.1.3
TxLength Port
The length of the frame to be transmitted is written
here immediately after the Transmit Command is
written.
base + 000Bh
3.2.1.4
Interrupt Status Queue Port
This port contains the current value of the Interrupt
Status Queue (ISQ). For a more detailed description of the ISQ, see Section 2.31, “Managing Interrupts & Status Queue”.
3.2.1.5
Ethernet Port Pointer
The Ethernet Port Pointer is written in order to access any of the Ethernet port indexed registers
(which reside in the 4 Kbyte memory page). The
first 12 bits (bits 0 through B) of the pointer provide
the offset of the target register to be accessed during the current operation. The next three bits (C, D,
and E) are read-only and will always read as 011b.
Any convenient value may be written to these bits
when writing to the Ethernet Port Pointer Port. The
last bit (Bit F) indicates whether or not the Ethernet
Port Pointer should be auto-incremented to the next
word location. Figure 22 shows the structure of the
Ethernet Port Pointer.
3.2.1.6
Ethernet Port Data Ports 0 and 1
The Ethernet Port Data Ports are used to transfer
data to and from any of the CS89712’s internal registers. Port 0 is used for 16-bit operations and Port
0 and 1 are used for 32-bit operations (lower-order
word in Port 0).
base + 000Ah
F E D C B A 9 8 7 6 5 4 3 2 1 0
Register Address
Bit F: 0 = Pointer remains fixed
1 = Auto-Increments to next word location
Figure 22. Ethernet Port Pointer
72
DS502PP2
CS89712
3.2.2
Ethernet Port Indexed Registers
Central to the Ethernet port architecture is a
4 Kbyte page of integrated RAM, which is used for
temporary storage of transmit and receive frames,
and for additional registers. These registers are accessed by use with the Ethernet Data Pointer and
Data Ports. These registers are organized into the
following sections:
3.2.2.1
Bus Interface Registers
The Bus Interface Registers contain Ethernet Port
interrupt enables, EEPROM control and data, and
receive frame information.
3.2.2.2
Status and Control Registers
The Status and Control registers are the primary
means of controlling and reading status of the
Ethernet port. They are detailed in Section 3.2.3,
“Ethernet Status/Control Registers”.
3.2.2.3
Initiate Transmit Registers
The TxCMD/TxLength registers are used to initiate
Ethernet frame transmission. These are detailed in
Section 3.19, “Initiate Transmit Registers”. (Also
see Section 2.34, “Transmit Operation” for a description of frame transmission.)
3.2.2.4
Address Filter Registers
The Filter registers store the Individual Address filter and Logical Address filter used by the Destination Address filter. These registers are described in
more detail in Section 3.20, “Address Filter Registers”. For a description of the DA filter, see Section
2.32.7, “Receive Ethernet Port Locations”.
3.2.2.5
Receive/Transmit Frame Locations
The Receive and Transmit Frame Ethernet Port locations are used to transfer Ethernet frames to and
from the host RAM. The software simply writes to
and reads from these locations and internal buffer
memory is dynamically allocated between transmit
and receive as needed. This provides more efficient
DS502PP2
use of buffer memory and better overall network
performance. As a result of this dynamic allocation, only one receive frame and one transmit frame
are directly accessible.
3.2.3
Ethernet Status/Control Registers
The Status and Control registers are the primary
registers used to control and check the status of the
Ethernet port in the CS89712. They are organized
into two groups: Configuration/Control Registers
and Status/Event Registers. All Status and Control
Registers are 16-bit words as shown in Figure 23.
Bit 0 indicates whether it is a Configuration/Control Register (Bit 0 = 1) or a Status/Event Register
(Bit 0 = 0). Bits 0 through 5 provide an internal address code that describes the exact function of the
register. Bits 6 through F are the actual Configuration/Control and Status/Event bits.
3.2.4
Configuration and Control Registers
Configuration and Control registers are used to setup the following:
•
how frames will be transmitted and received;
•
which frames will be transmitted and received;
•
which events will cause interrupts to the processor; and,
•
Configuration of the Ethernet physical interface.
These registers are read/write and are designated
by odd numbers (e.g. Register 1, Register 3, etc.).
The Transmit Command Register (TxCMD) is a
special type of register. It appears in two separate
locations in the Ethernet Port memory map. The
first location, Ethernet Port offset address 0108h, is
within the block of Configuration/Control Registers and is read-only. The second location, Ethernet
Port offset address 0144h, is where the actual transmit commands are issued and is write-only. See
Section 3.2.7, “Status/Control Register Summary”
and Section 2.34, “Transmit Operation” for a more
detailed description of the TxCMD register.
73
CS89712
3.2.5
Status and Event Registers
Status and Event registers report the status of transmitted and received frames, as well as information
about the configuration of the CS89712. They are
read-only.
The Interrupt Status Queue (ISQ) is a special type
of Status/Event register. It is located at Ethernet
Port offset address 0120h and is the first register
the software reads when responding to an Interrupt.
A more detailed description of the ISQ can be
found in Section 2.31, “Managing Interrupts &
Status Queue”.
Three 10-bit counters are included with the Status
and Event registers. RxMISS counts missed receive frames, TxCOL counts transmit collisions.
Table 34 summarizes Ethernet Port Register types.
3.2.6
Status and Control Bit Definitions
This section provides a description of the special
bit types used in the Status and Control registers.
16-bit Register Word
Bit Number
F E D C B A 9 8 7 6 5 4 3 2 1 0
Internal Address
(bits 0 - 5)
1 = Control/Configuration
0 = Status/Event
10 Register Bits
Figure 23. Status and Control Register Format
Suffix
Type
Description
CMD
Read/Write
Command: Written once per frame to initiate transmit.
CFG
Read/Write
Configuration: Written at setup and used to determine
what frames will be transmitted and received and what
events will cause interrupts.
CTL
Read/Write
Control: Written at setup and used to determine what
frames will be transmitted and received and how the physical interface will be configured.
Event
Read-only
Event: Reports the status of transmitted and received
frames.
ST
Read-only
Status: Reports information about the configuration of the
CS89712.
Read-only
Counters: Counts missed receive frames and collisions.
Provides time domain for locating coax cable faults.
Comments
cleared when read
cleared when read
Table 34. Ethernet Port Register Types
74
DS502PP2
CS89712
Section 3.2.7, “Status/Control Register Summary”
provides a detailed description of each register.
3.2.6.1
Act-Once Bits
There are four bits that cause a certain action only
once when set. These "Act-Once" bits are: Skip_1
(RxCFG register bit 6), RESET (SelfCTL register
bit 6), ResetRxDMA (BusCTL register bit 6), and
SWint-X (BufCFG register bit 6). To cause the action again, the software must set the bit again. ActOnce bits are always read as clear.
3.2.6.2
Temporal Bits
Temporal bits are bits that are set and cleared by the
Ethernet port automatically. This includes all status
bits in the three status registers (LineST, SelfST,
and BusST), the RxDest bit (BufEvent bit F), and
the Rx128 bit (BufEvent bit B). Like all Event bits,
RxDest and Rx128 are cleared when read by the
software.
3.2.6.3
Interrupt Enable Bits and Events
Interrupt Enable bits end with the suffix iE and are
located in three Configuration registers: RxCFG,
TxCFG, and BufCFG. Each Interrupt Enable bit
corresponds to a specific event. If an Interrupt Enable bit is set and its corresponding event occurs,
the Ethernet port generates an interrupt.
The bits that report when various events occur are
located in three Event registers and two counters.
The Event registers are RxEvent, TxEvent, and
BufEvent. The counters are RxMISS and TxCOL.
Each Interrupt Enable bit and its associated Event
are identified in Table 35.
An Event bit will be set whenever the specified
event happens, whether or not the associated Interrupt Enable bit is set. All Event registers are cleared
upon read-out by the software.
3.2.6.4
Accept Bits
There are nine Accept bits located in the RxCTL
register, each of which is followed by the suffix A.
DS502PP2
Interrupt Enable Bit
(register name)
Event Bit or Counter
(register name)
ExtradataiE (RxCFG)
Extradata (RxEvent)
RuntiE (RxCFG)
Runt (RxEvent)
CRCerroriE (RxCFG)
CRCerror (RxEvent)
RxOKiE (RxCFG)
RxOK (RxEvent)
16colliE (TxCFG)
16coll (TxEvent)
AnycolliE (TxCFG)
“Number-of Tx-collisions” counter is incremented (TxEvent)
JabberiE (TxCFG)
Jabber (TxEvent)
Out-of-windowiE (TxCFG) Out-of-window (TxEvent)
TxOKiE (TxCFG)
TxOK (TXEvent)
MissOvfloiE (BufCFG)
RxMISS counter overflows past 1FFh
TxColOvfloiE (BufCFG)
TxCOL counter overflows
past 1FFh
RxDestiE (BufCFG)
RxDest (BufEvent)
Rx128iE (BufCFG)
Rx128 (BufEvent)
RxMissiE (BufCFG)
RxMISS (BufEvent)
TxUnderruniE (BufCFG)
TxUnderrun (BufEvent)
Rdy4TxiE (BufCFG)
Rdy4Tx (BufEvent)
Table 35. Interrupt Enable Bits and Events
Accept bits indicate which types of frames will be
accepted by the CS89712. Four of these bits have
corresponding Interrupt Enable (iE) bits. An Accept bit and an Interrupt Enable bit are independent
operations. It is possible to set either, neither, or
both bits. The four corresponding pairs of bits are:
IE Bit in RxCFG
ExtradataiE
RuntiE
CRCerroriE
RxOKiE
A Bit in RxCTL
ExtradataA
RuntA
CRCerrorA
RxOKA
If one of the above Interrupt Enable bits is set and
the corresponding Accept bit is clear, the CS89712
75
CS89712
generates an interrupt when the associated receive
event occurs, but then does not accept the receive
frame (the receive frame length is set to zero).
The other five Accept bits in RxCTL are used for
destination address filtering (see Section 2.32.7,
“Receive Ethernet Port Locations”). The Accept
76
mechanism is explained in more detail in Section
2.32, “Basic Receive Operation”.
3.2.7
Status/Control Register Summary
This section gives a detailed description of each
Status and Control register. Bits marked “RSVD”
are reserved and must be written with a zero for
proper operation of the device.
DS502PP2
CS89712
3.3 Ethernet Port 4 Kbyte Memory Register Map
The following Table shows the CS89712 Ethernet Port internal register map:
Internal
Offset
# of
Bytes
Bus Interface Registers
0000h
4
0004h
28
0022h
2
Type
Description
Cross Reference
Reserved
RW
Reserved
Note 2
Master Interrupt Enable
Section 3., “REGISTER SET”,
Section 3.17, “Ethernet Bus Interface Registers”
0038h
8
-
Reserved
Note 2
0040h
2
RW
EEPROM Command
Section 2.24, “Programming the EEPROM”,
Section 3.17, “Ethernet Bus Interface Registers”
0042h
2
RW
EEPROM Data
Section 2.24, “Programming the EEPROM”,
Section 3.17, “Ethernet Bus Interface Registers”
0044h
12
-
Reserved
Note 2
0050h
2
RD
Received Frame Byte
Counter
0052h
174
-
Section 3.17, “Ethernet Bus Interface Registers”,
Section 2.32, “Basic Receive Operation”
Note 2
Status and Control Registers
0102
2
RW
Reserved
Receive Configuration
0104
2
RW
Receive Control
0106
2
RW
Transmit Configuration
0108
2
RW
Transmit Command
010A
2
RW
Buffer Configuration
0112
2
RW
Line Control
0114
2
RW
Self Control
0116
2
RW
Bus Control
0118
2
RW
Test Control
0120
2
RD
Interrupt Status Queue
0124
2
RD
Receive Event
0124
2
RD
alternate Receive Event
0128
2
RD
Transmit Event
012C
2
RD
Buffer Event
0130
2
RD
Receive Miss
0132
2
RD
Transmit Collision
0134
2
RD
Line Status
0136
2
RD
Self Status
Section 3.2.3, “Ethernet Status/Control
Registers”
see above
see above
see above
see above
see above
see above
see above
see above
Table 36. Ethernet Port 4 Kbyte Memory Register Address Map
DS502PP2
77
CS89712
Internal
Offset
# of
Bytes
Type
0138
2
RD
Bus Status
0140h
4
-
Reserved
Note 2
WR
TxCMD (transmit
command)
Section 3.19, “Initiate Transmit Registers”,
Section 2.34, “Transmit Operation”
TxLength (transmit length)
Section 3.19, “Initiate Transmit Registers”,
Section 2.34, “Transmit Operation”
Reserved
Note 2
RW
Logical Address Filter
(hash table)
Section 3.20, “Address Filter Registers”,
Section 2.32.7, “Receive Ethernet Port
Locations”
Individual Address
Section 3.20, “Address Filter Registers”,
Section 2.32.7, “Receive Ethernet Port
Locations”
Reserved
Note 2
RXStatus (receive status)
Section 3.18, “Ethernet Port Status/Control
Registers”,
Section 2.32, “Basic Receive Operation”
Section 3.18, “Ethernet Port Status/Control
Registers”,
Section 2.32, “Basic Receive Operation”
Section 3.18, “Ethernet Port Status/Control
Registers”,
Section 2.32, “Basic Receive Operation”
Section 3.18, “Ethernet Port Status/Control
Registers”,
Section 2.34, “Transmit Operation”
Initiate Transmit Registers
0144h
2
0146h
2
WR
0148h
8
-
Address Filter Registers
0150h
8
0158h
6
RW
015Eh
674
-
2
RD
Frame Location
0400h
Description
0402h
2
Read-only RxLength (receive length,
in bytes)
0404h
-
Read-only Receive Frame Location
0A00
-
Write-only Transmit Frame Location
Cross Reference
Table 36. Ethernet Port 4 Kbyte Memory Register Address Map (Continued)
Notes: 1. All registers are accessed as 16-bit only.
2. Read operation from the reserved location provides undefined data. Writing to a reserved location or
undefined bits may result in unpredictable operation.
3.4 I/O Port Data Registers
3.4.1
PADR Port A Data Register (address 0x8000.0000)
Values written to this 8-bit read / write register will be output on Port A pins if the corresponding data direction bits are set high (port output). Values read from this register reflect the external state of Port A, not necessarily the value written to it. All bits are cleared by a system reset.
3.4.2
PBDR Port B Data Register (address 0x8000.0001)
Values written to this 8-bit read / write register will be output on Port B pins if the corresponding data direction bits are set high (port output). Values read from this register reflect the external state of Port B, not necessarily the value written to it. All bits are cleared by a system reset.
78
DS502PP2
CS89712
3.4.3
PDDR Port D Data Register (address 0x8000.0003)
Values written to this 8-bit read / write register will be output on Port D pins if the corresponding data direction bits are set low (port output). Values read from this register reflect the external state of Port D, not necessarily the value written to it. All bits are cleared by a system reset.
3.4.4
PADDR Port A Data Direction Register (address 0x8000.0040)
Bits set in this 8-bit read / write register will select the corresponding pin in Port A to become an output, clearing a bit sets the pin to input. All bits are cleared by a system reset.
3.4.5
PBDDR Port B Data Direction Register (address 0x8000.0041)
Bits set in this 8-bit read / write register will select the corresponding pin in Port B to become an output, clearing a bit sets the pin to input. All bits are cleared by a system reset.
3.4.6
PDDDR Port D Data Direction Register (address 0x8000.0043)
Bits cleared in this 8-bit read / write register will select the corresponding pin in Port D to become an output,
setting a bit sets the pin to input. All bits are cleared by a system reset so that Port D is output by default.
3.4.7
PEDR Port E Data Register (address 0x8000.0080)
Values written to this 3-bit read / write register will be output on Port E pins if the corresponding data direction bits are set high (port output). Values read from this register reflect the external state of Port E, not necessarily the value written to it. All bits are cleared by a system reset.
3.4.8
PEDDR Port E Data Direction Register (address 0x8000.00C0)
Bits set in this 3-bit read / write register will select the corresponding pin in Port E to become an output, while
the clearing bit sets the pin to input. All bits are cleared by a system reset so that Port E is input by default.
3.5 System Control Registers
3.5.1
SYSCON1 The System Control Register 1 (address 0x8000.0100)
23:21
20
19
18
17:16
15
Reserved
IRTXM
WAKEDIS
EXCKEN
ADCKSEL
SIREN
14
13
12
11
10
9
CDENRX
CDENTX
LCDEN
DBGEN
BZMOD
BZTOG
8
7
6
5
4
3:0
UART1EN
TC2S
TC2M
TC1S
TC1M
Keyboard scan
The system control register is a 21-bit read / write register which controls all the general configuration of the
CS89712, as well as modes etc. for peripheral devices. All bits in this register are cleared by a system reset. The
bits in the system control register SYSCON1 are defined in Table 37.
DS502PP2
79
CS89712
Bit
0:3
Description
Keyboard scan: This 4-bit field defines the state of the keyboard column drives. The following
table defines these states.
Keyboard Scan
0
1
2–7
8
9
10
11
12
13
14
15
Column
All driven high
All driven low
All high impedance (tristate)
Column 0 only driven high all others high impedance
Column 1 only driven high all others high impedance
Column 2 only driven high all others high impedance
Column 3 only driven high all others high impedance
Column 4 only driven high all others high impedance
Column 5 only driven high all others high impedance
Column 6 only driven high all others high impedance
Column 7 only driven high all others high impedance
4
TC1M: Timer counter 1 mode. Setting this bit sets TC1 to prescale mode, clearing it sets free running mode.
5
TC1S: Timer counter 1 clock source. Setting this bit sets the TC1 clock source to 512 kHz, clearing it sets the clock source to 2 kHz.
6
TC2M: Timer counter 2 mode. Setting this bit sets TC2 to prescale mode, clearing it sets free running mode.
7
TC2S: Timer counter 2 clock source. Setting this bit sets the TC2 clock source to 512 kHz, clearing it sets the clock source to 2 kHz.
8
UART1EN: Internal UART enable bit. Setting this bit enables the internal UART.
9
BZTOG: Bit to drive (i.e., toggle) the buzzer output directly when software mode of operation is
selected (i.e., bit BZMOD = 0). See the BZMOD and BUZFREQ (SYSCON1) bits for more
details.
10
BZMOD: This bit selects the buzzer drive mode. When BZMOD = 0, the buzzer drive output pin
is connected directly to the BZTOG bit. This is the software mode. When BZMOD = 1, the buzzer
drive is in the hardware mode. Two hardware sources are available to drive the pin. They are the
TC1 or a fixed internally generated clock source. The selection of which source is used to drive
the pin is determined by the state of the BUZFREQ bit in the SYSCON2 register. If the TC1 is
selected, then the buzzer output pin is connected to the TC1 under flow bit. The buzzer output
pin changes every time the timer wraps around. The frequency depends on what was programmed into the timer. See the description of the BUZFREQ and BZTOG bits (SYSCON2) for
more details.
Table 37. SYSCON1
80
DS502PP2
CS89712
Bit
Description
11
DBGEN: Setting this bit will enable the debug mode. In this mode, all internal accesses are output as if they were reads or writes to the expansion memory addressed by nCS5. nCS5 will still
be active in its standard address range. In addition, the internal interrupt request and fast interrupt request signals to the ARM720T processor are output on Port E, bits 1 and 2. Note that
these bits must be programmed to be outputs before this functionality can be observed. The
clock to the CPU is output on Port E, Bit 0 to delineate individual accesses. For example, in
debug mode:
nCS5 = nCS5 or internal I/O strobe
PE0 = CLK
PE1 = nIRQ
PE2 = nFIQ
12
LCDEN: LCD enable bit. Setting this bit enables the LCD controller.
13
CDENTX: Codec interface enable TX bit. Setting this bit enables the codec interface for data
transmission to an external codec device.
14
CDENRX: Codec interface enable RX bit. Setting this bit enables the codec interface for data
reception from an external codec device.
Note: Both CDENRX and CDENTX need to be enabled / disabled in tandem, otherwise data may
be lost.
15
SIREN: HP SIR protocol encoding enable bit. This bit will have no effect if the UART is not
enabled.
16:17
ADCKSEL: Microwire / SPI peripheral clock speed select. This two-bit field selects the frequency
of the ADC sample clock, which is twice the frequency of the synchronous serial ADC interface
clock. The table below shows the available frequencies for operation when in PLL mode. These
bits are also used to select the shift clock frequency for the SSI2 interface when set into master
mode.
ADCKSEL
00
01
10
11
ADC Sample Frequency
(kHz) — SMPCLK
8
32
128
256
ADC Clock Frequency
(kHz) — ADCCLK
4
16
64
128
18
EXCKEN: External expansion clock enable. If this bit is set, the EXPCLK is enabled continuously
as a free running clock with the same frequency and phase as the CPU clock, assuming that the
main oscillator is running. This bit should not be left set all the time for power consumption reasons. If the system enters the Standby State, the EXPCLK will become undefined. If this bit is
clear, EXPCLK will be active during memory cycles to expansion slots that have external wait
state generation enabled only.
19
WAKEDIS: Setting this bit disables waking up (exiting) from the Standby State, from either the
WAKEUP input pin or a keypress after one of the following signals became active: nPWRFL,
BATOK, nEXTPWR.
Note: Even though a keypress will not wake the device, a keypress interrupt will still be generated,
if the keyboard interrupt is not masked, and this can be used to wake the device.
Table 37. SYSCON1 (Continued)
DS502PP2
81
CS89712
Bit
20
Description
IRTXM: IrDA TX mode bit. This bit controls the IrDA encoding strategy. Clearing this bit means
that each zero bit transmitted is represented as a pulse of width 3/16th of the bit rate period. Setting this bit means each zero bit is represented as a pulse of width 3/16th of the period of
115,200-bit rate clock (i.e., 1.6 µsec regardless of the selected bit rate). Setting this bit will use
less power, but will probably reduce transmission distances.
Table 37. SYSCON1 (Continued)
82
DS502PP2
CS89712
3.5.2
SYSCON2 System Control Register 2 (address 0x8000.1100)
15
14
13
12
11:10
9
8
Reserved
BUZFREQ
CLKENSL
OSTB
Reserved
SS2MAEN
UART2EN
7
6
5
4
3
2
1
0
SS2RXEN
PC CARD2
PC CARD1
SS2TXEN
KBWEN
DRAMSZ
KBD6
SERSEL
This is an extension of SYSCON1, containing additional control for the CS89712. The bits of this second system
control register are defined below. The SYSCON2 register is reset to all 0s on power up.
Bit
0
Description
SERSEL:The only affect of this bit is to select either SSI2 or the codec to interface to the external
pins. See the table below for the selection options.
NOTE: If the DAI bit of SYSCON3 is set, then it overrides the state of the SERSEL bit, and thus
the external pins are connected to the DAI interface.
SERSEL Value
0
1
Selected Serial Device to
External Pins
Master / slave SSI2
Codec
1
KBD6: The state of this bit determines how many of the Port A inputs are OR’ed together to create the keyboard interrupt. When zero (the reset state), all eight of the Port A inputs will generate
a keyboard interrupt. When set high, only Port A bits 0 to 5 will generate an interrupt from the
keyboard. It is assumed that the keyboard row lines are connected into Port A.
2
DRAMZ: This bit determines the width of the DRAM memory interface, where: 0=32-bit DRAM
and 1=16-bit DRAM.
3
KBWEN: When the KBWEN bit is high, the CS89712 will awaken from a power saving state into
the Operating State when a high signal is on one of Port A’s inputs (irrespective of the state of the
interrupt mask register). This is called the Keyboard Direct Wakeup mode. In this mode, the interrupt request does not have to get serviced. If the interrupt is masked (i.e., the interrupt mask register 2 (INTMR2) bit 0 is low), the processor simply starts re-executing code from where it left off
before it entered the power saving state. If the interrupt is non-masked, then the processor will
service the interrupt.
4
SS2TXEN: Transmit enable for the synchronous serial interface 2. The transmit side of SSI2 will
be disabled until this bit is set. When set low, this bit also disables the SSICLK pin (to save
power) in master mode, if the receive side is low.
5
PC CARD1: Enable for the interface to the CL-PS6700 device for PC Card slot 1. The main effect
of this bit is to reassign the functionality of Port B, bit 0 to the PRDY input from the CL-PS6700
devices, and to ensure that any access to the nCS4 address space will be according to the
CL-PS6700 interface protocol.
6
PC CARD2: Enable for the interface to the CL-PS6700 device for PC Card slot 2. The main effect
of this bit is to reassign the functionality of Port B, bit 1 to the PRDY input from the CL-PS6700
devices and to ensure that any access to the nCS5 address space will be according to the
CL-PS6700 interface protocol.
Table 38. SYSCON2
DS502PP2
83
CS89712
Bit
Description
7
SS2RXEN: Receive enable for the synchronous serial interface 2. The receive side of SSI2 will
be disabled until this bit is set. When both SSI2TXEN and SSI2RXEN are disabled, the SSI2
interface will be in a power saving state.
8
UART2EN: Internal UART2 enable bit. Setting this bit enables the internal UART2.
9
SS2MAEN: Master mode enable for the synchronous serial interface 2. When low, SSI2 will be
configured for slave mode operation. When high, SSI2 will be configured for master mode operation. This bit also controls the directionality of the interface pins.
10
SNZPOL: Snooze State LCD data polarity bit. When low, the LCD controller will put out ‘0000’ on
the DD[3:0] outputs during the blanked parts of the display in Snooze State. When high, ‘1111’
will be output instead. This is to allow the connection of displays with inverse polarity. During normal Operating State, an inverse polarity display is handled by appropriate programming of the
palette, and this bit will have no effect.
11
LCDSNZE: This bit is normally set low, but will be automatically set high on entering Snooze
State. While this bit is high, data will be fetched from the on-chip SRAM for the display. When
Snooze State is exited, this bit will have been set high and this will have the effect of causing the
LCD controller to continue to fetch data from the on-chip SRAM, in 1-bit-per-pixel mode, irrespective of the contents of the LCDCON register. This ensures that the display does not change on
exit from Snooze State, so that if the exit is for a simple update-on-interrupt operation the display
need not be affected. Additional arbitration is included so that the on-chip SRAM can be written to
while the LCDSNZE bit is set after Snooze State. If the exit from Snooze State has occurred
because the device was to be completely woken up, including switching to the main LCD frame
buffer, (whose start address is defined in the FBADDR register) then this can be achieved by writing a 0 to the LCDSNZE bit, which will cause the CL-CS89712 to start fetching DMA data from
the main buffer and sync up the display at the end of the following frame. The LCDSNZE bit can
never be programmed to 1 by the CPU — the value ‘1’ will be ignored.
12
Reserved: This bit should be set low.
13
CLKENSL: CLKEN select. When low, the CLKEN signal will be output on the RUN/CLKEN pin.
When high, the RUN signal will be output on RUN/CLKEN.
14
BUZFREQ: The BUZFREQ bit is used to select which hardware source will be used as the
source to drive the buzzer output pin. When BUZFREQ = 0, the buzzer signal generated from the
on-chip timer (TC1) is output. When BUZFREQ = 1, a 500 Hz clock is output. See the BZMOD
and the BZTOG bits (SYSCON2) for more details.
Table 38. SYSCON2 (Continued)
84
DS502PP2
CS89712
3.5.3
SYSCON3 System Control Register 3 (address 0x8000.2200)
15
14
13
12
11
10
9
8
Reserved
Reserved
Reserved
Reserved
Reserved
ENPD67
128Fs
FASTWAKE
7
6
5
4
3
2
1
0
VERSN[2]
Reserved
VERSN[1]
Reserved
VERSN[0]
Reserved
ADCCKNSEN
DAISEL
CLKCTL1
CLKCTL0
ADCCON
This register allows additional control for the CS89712. The bits of this register are defined in Table 38.
Bit
Description
0
ADCCON: Determines whether the ADC Configuration Extension field SYNCIO(31:16) is to be
used for ADC configuration data. When this bit = 0 (default state) the ADC Configuration Byte
SYNCIO(7:0) only is used for compatibility with the CL-PS7111. When this bit = 1, the ADC Configuration Extension field in the SYNCIO register is used for ADC Configuration data and the
value in the ADC Configuration Byte (SYNCIO(6:0)) selects the length of the data (8-bit to 16-bit).
1:2
CLKCTL(1:0): Determines the frequency of operation of the processor and Wait State scaling.
The table below lists the available options.
CLKCTL(1:0)
Value
00
01
10
11
Processor
Frequency
18.432 MHz
36.864 MHz
49.152 MHz
73.728 MHz
Memory Bus
Frequency
18.432 MHz
36.864 MHz
36.864 MHz
36.864 MHz
Wait State Scaling
1
2
2
2
Note: To determine the number of wait states programmed refer to Table 46 and Table 47. Under
no circumstances should the CLKCTL bits be changed using a buffered write.
3
DAISEL: When set selects the DAI Interface. When cleared selects either the SSI or telephony
codec interface (i.e., DAISEL bit is default low).
4
ADCCKNSEN: When set, configuration data is transmitted on ADCOUT at the rising edge of the
ADCCLK, and data is read back on the falling edge on the ADCIN pin. When clear (default), the
opposite edges are used.
5:7
VERSN[0:2]: Additional read-only version bits — will read ‘000’
8
Reserved. This bit must be set to zero
9
128Fs: When set, this selects the 128 fs mode. Cleared by default to enable 64 fs operation.
10
ENPD67: Pd[6-7] control the byte mask of the SDRAM interface. Setting of this bit allows their
use as GPIO bits for applications not using SDRAM.
Table 39. SYSCON3
DS502PP2
85
CS89712
3.5.4
SYSFLG1 — The System Status Flags Register (address 0x8000.0140)
31:30
29
28
27
26
VERID
ID
BOOTBIT1
BOOTBIT0
SSIBUSY
25
24
23
22
21:16
CTXFF
CRXFE
UTXFF1
URXFE1
RTCDIV
15
14
13
12
11
CLDFLG
PFFLG
RSTFLG
NBFLG
UBUSY1
7:4
3
2
1
0
DID
WUON
WUDR
DCDET
MCDR
The system status flags register is a 32-bit read only register, which indicates various system information. The bits
in the system status flags register SYSFLG1 are defined in Table 40.
Bit
Description
0
MCDR: Media changed direct read. This bit reflects the INVERTED non-latched status of the
media changed input.
1
DCDET: This bit will be set if a non-battery operated power supply is powering the system (it is
the inverted state of the nEXTPWR input pin).
2
WUDR: Wake up direct read. This bit reflects the non-latched state of the wakeup signal.
3
WUON: This bit will be set if the system has been brought out of the Standby State by a rising
edge on the wakeup signal. It is cleared by a system reset or by writing to the HALT or STDBY
locations.
4:7
DID: Display ID nibble. This 4-bit nibble reflects the latched state of the four LCD data lines. The
state of the four LCD data lines is latched by the LCDEN bit, and so it will always reflect the last
state of these lines before the LCD controller was enabled.
8
CTS: This bit reflects the current status of the clear to send (CTS) modem control input to
UART1.
9
DSR: This bit reflects the current status of the data set ready (DSR) modem control input to
UART1.
10
DCD: This bit reflects the current status of the data carrier detect (DCD) modem control input to
UART1.
11
UBUSY1: UART1 transmitter busy. This bit is set while UART1 is busy transmitting data, it is
guaranteed to remain set until the complete byte has been sent, including all stop bits.
12
NBFLG: New battery flag. This bit will be set if a low to high transition has occurred on the
nBATCHG input, it is cleared by writing to the STFCLR location.
13
RSTFLG: Reset flag. This bit will be set if the RESET button has been pressed, forcing the
nURESET input low. It is cleared by writing to the STFCLR location.
14
PFFLG: Power Fail Flag. This bit will be set if the system has been reset by the nPWRFL input
pin, it is cleared by writing to the STFCLR location.
15
CLDFLG: Cold start flag. This bit will be set if the CS89712 has been reset with a power on reset,
it is cleared by writing to the STFCLR location.
Table 40. SYSFLG
86
DS502PP2
CS89712
Bit
Description
16:21
RTCDIV: This 6-bit field reflects the number of 64 Hz ticks that have passed since the last increment of the RTC. It is the output of the divide by 64 chain that divides the 64 Hz tick clock down
to 1 Hz for the RTC. The MSB is the 32 Hz output, the LSB is the 1 Hz output.
22
URXFE1: UART1 receiver FIFO empty. The meaning of this bit depends on the state of the UFIFOEN bit in the UART1 bit rate and line control register. If the FIFO is disabled, this bit will be set
when the RX holding register is empty. If the FIFO is enabled, the URXFE bit will be set when the
RX FIFO is empty.
23
UTXFF1: UART1 transmit FIFO full. The meaning of this bit depends on the state of the UFIFOEN bit in the UART1 bit rate and line control register. If the FIFO is disabled, this bit will be set
when the TX holding register is full. If the FIFO is enabled, the UTXFF bit will be set when the TX
FIFO is full.
24
CRXFE: Codec RX FIFO empty bit. This will be set if the 16-byte codec RX FIFO is empty.
25
CTXFF: Codec TX FIFO full bit. This will be set if the 16-byte codec TX FIFO is full.
26
SSIBUSY: Synchronous serial interface busy bit. This bit will be set while data is being shifted in
or out of the synchronous serial interface, when clear data is valid to read.
27:28
BOOTBIT0–1: These bits indicate the default (power-on reset) bus width of the ROM interface.
See Memory Configuration Registers for more details on the ROM interface bus width. The state
of these bits reflect the state of Port E[0:1] during power on reset, as shown in the table below.
PE[1]
(BOOTBIT1)
0
0
1
1
PE[0]
(BOOTBIT0)
0
1
0
1
Boot option
32-bit
8-bit
16-bit
Reserved
29
ID: Will always read ‘1’ for the CS89712 device.
30:31
VERID: Version ID bits. These 2 bits determine the version id for the CS89712. Will read ‘10’ for
the initial version.
Table 40. SYSFLG (Continued)
DS502PP2
87
CS89712
3.5.5
SYSFLG2 System Status Register 2 (address 0x8000.1140)
23
22
21:12
11
10:7
6
UTXFF2
URXFE2
Reserved
UBUSY2
Reserved
CKMODE
5
4
3
2
1
0
SS2TXUF
SS2TXFF
SS2RXFE
RESFRM
RESVAL
SS2RXOF
This register is an extension of SYSFLG1, containing status bits for backward compatibility with CL-PS7111. The
bits of the second system status register are defined in Table 41.
Bit
Description
0
SS2RXOF: Master / slave SSI2 RX FIFO overflow. This bit is set when a write is attempted to a
full RX FIFO (i.e., when RX is still receiving data and the FIFO is full). This can be cleared in one
of two ways:
1. Empty the FIFO (remove data from FIFO) and then write to SRXEOF location.
2. Disable the RX (affects of disabling the RX will not take place until a full SSI2 clock cycle after
it is disabled)
1
RESVAL: Master / slave SSI2 RX FIFO residual byte present, cleared by popping the residual
byte into the SSI2 RX FIFO or by a new RX frame sync pulse.
2
RESFRM: Master / slave SSI2 RX FIFO residual byte present, cleared only by a new RX frame
sync pulse.
3
SS2RXFE: Master / slave SSI2 RX FIFO empty bit. This will be set if the 16 x 16 RX FIFO is
empty.
4
SS2TXFF: Master / slave SSI2 TX FIFO full bit. This will be set if the 16 x 16 TX FIFO is full. This
will get cleared when data is removed from the FIFO or the CS89712 is reset.
5
SS2TXUF: Master / slave SSI2 TX FIFO Underflow bit. This will be set if there is attempt to transmit when TX FIFO is empty. This will be cleared when FIFO gets loaded with data.
6
CKMODE: This bit reflects the status of the CLKSEL (PE[2]) input, latched on power on reset.
This bit should be low.
11
UBUSY2: UART2 transmitter busy. This bit is set while UART2 is busy transmitting data; it is
guaranteed to remain set until the complete byte has been sent, including all stop bits.
22
URXFE2: UART2 receiver FIFO empty. The meaning of this bit depends on the state of the UFIFOEN bit in the UART2 bit rate and line control register. If the FIFO is disabled, this bit will be set
when the RX holding register contains is empty. If the FIFO is enabled, the URXFE bit will be set
when the RX FIFO is empty.
23
UTXFF2: UART2 transmit FIFO full. The meaning of this bit depends on the state of the UFIFOEN bit in the UART2 bit rate and line control register. If the FIFO is disabled, this bit will be set
when the TX holding register is full. If the FIFO is enabled, the UTXFF bit will be set when the TX
FIFO is full.
Table 41. SYSFLG2
88
DS502PP2
CS89712
3.6 Interrupt Registers
3.6.1
INTSR1 Interrupt Status Register 1 (address 0x8000.0240)
15
14
13
12
11
10
9
8
SSEOTI
UMSINT
URXINT1
UTXINT1
TINT
RTCMI
TC2OI
TC1OI
7
6
5
4
3
2
1
0
EINT3
EINT2
EINT1
CSINT
MCINT
WEINT
BLINT
EXTFIQ
The interrupt status register is a 32-bit read only register. The interrupt status register reflects the current state of
the first 16 interrupt sources within the CS89712. Each bit is set if the appropriate interrupt is active. The interrupt
assignment is given in Table 42.
Bit
Description
0
EXTFIQ: External fast interrupt. This interrupt will be active if the nEXTFIQ input pin is forced low and is
mapped to the FIQ input on the ARM720T processor.
1
BLINT: Battery low interrupt. This interrupt will be active if no external supply is present (nEXTPWR is
high) and the battery OK input pin BATOK is forced low. This interrupt is deglitched with a 16 kHz clock,
so it will only generate an interrupt if it is active for longer than 125 µsec. It is mapped to the FIQ input
on the ARM720T processor and is cleared by writing to the BLEOI location.
Note: BLINT is disabled during Snooze/the Standby States.
2
WEINT: Tick Watch dog expired interrupt. This interrupt will become active on a rising edge of the periodic 64 Hz tick interrupt clock if the tick interrupt is still active (i.e., if a tick interrupt has not been serviced for a complete tick period). It is mapped to the FIQ input on the ARM720T processor and the TEOI
location.
Notes: 1. WEINT is disabled during Snooze/the Standby States.
2. Watch dog timer tick rate is 64 Hz.
3. Watchdog timer is turned off during Snooze/the Standby States.
3
MCINT: Media changed interrupt. This interrupt will be active after a rising edge on the nMEDCHG input
pin has been detected, This input is deglitched with a 16 kHz clock so it will only generate an interrupt if
it is active for longer than 125 µsec. It is mapped to the FIQ input on the ARM7TDMI processor and is
cleared by writing to the MCEOI location. On power-up, the Media change pin (nMEDCHG) is used as
an input to force the processor to either boot from the internal Boot ROM, or from external memory.
After power-up, the pin can be used as a general purpose FIQ interrupt pin.
4
CSINT: Codec sound interrupt, generated when the data FIFO has reached half full or empty (depending on the interface direction). It is cleared by writing to the COEOI location.
5
EINT1: External interrupt input 1. This interrupt will be active if the nEINT1 input is active (low). It is
cleared by returning nEINT1 to the passive (high) state.
6
EINT2: External interrupt input 2. This interrupt will be active if the nEINT2 input is active (low). It is
cleared by returning nEINT2 to the passive (high) state.
7
EINT3: Interrupt input 3 (Ethernet port). This interrupt will be active if the Ethernet port requests an
interrupt. It is cleared by returning EINT3 to the passive (low) state.
8
TC1OI: TC1 under flow interrupt. This interrupt becomes active on the next falling edge of the timer
counter 1 clock after the timer counter has under flowed (reached zero). It is cleared by writing to the
TC1EOI location.
Table 42. INTSR1
DS502PP2
89
CS89712
Bit
Description
9
TC2OI: TC2 under flow interrupt. This interrupt becomes active on the next falling edge of the timer
counter 2 clock after the timer counter has under flowed (reached zero). It is cleared by writing to the
TC2EOI location.
10
RTCMI: RTC compare match interrupt. This interrupt becomes active on the next rising edge of the
1 Hz Real-Time Clock (one second later) after the 32-bit time written to the Real-Time Clock match register exactly matches the current time in the RTC. It is cleared by writing to the RTCEOI location.
11
TINT: 64 Hz tick interrupt. This interrupt becomes active on every rising edge of the internal
64 Hz clock signal. This 64 Hz clock is derived from the 15-stage ripple counter that divides the
32.768 kHz oscillator input down to 1 Hz for the Real-Time Clock. This interrupt is cleared by writing to
the TEOI location.
Note: TINT is disabled / turned off during Snooze/the Standby States.
12
UTXINT1: Internal UART1 transmit FIFO half-empty interrupt. The function of this interrupt source
depends on whether the UART1 FIFO is enabled. If the FIFO is disabled (FIFOEN bit is clear in the
UART1 bit rate and line control register), this interrupt will be active when there is no data in the UART1
TX data holding register and be cleared by writing to the UART1 data register. If the FIFO is enabled
this interrupt will be active when the UART1 TX FIFO is half or more empty, and is cleared by filling the
FIFO to at least half full.
13
URXINT1: Internal UART1 receive FIFO half full interrupt. The function of this interrupt source depends
on whether the UART1 FIFO is enabled. If the FIFO is disabled this interrupt will be active when there is
valid RX data in the UART1 RX data holding register and be cleared by reading this data. If the FIFO is
enabled this interrupt will be active when the UART1 RX FIFO is half or more full or if the FIFO is non
empty and no more characters have been received for a three character time out period. It is cleared by
reading all the data from the RX FIFO.
14
UMSINT: Internal UART1 modem status changed interrupt. This interrupt will be active if either of the
two modem status lines (CTS or DSR) change state. It is cleared by writing to the UMSEOI location.
15
SSEOTI: Synchronous serial interface end of transfer interrupt. This interrupt will be active after a complete data transfer to and from the external ADC has been completed. It is cleared by reading the ADC
data from the SYNCIO register.
Table 42. INTSR1 (Continued)
3.6.2
INTMR1 Interrupt Mask Register 1 (address 0x8000.0280)
15
14
13
12
11
10
9
8
SSEOTI
UMSINT
URXINT
UTXINT
TINT
RTCMI
TC2OI
TC1OI
7
6
5
4
3
2
1
0
EINT3
EINT2
EINT1
CSINT
MCINT
WEINT
BLINT
EXTFIQ
This interrupt mask register is a 32-bit read / write register, which is used to selectively enable any of the first 16
interrupt sources within the CS89712. The four shaded interrupts all generate a fast interrupt request to the
ARM720T processor (FIQ), this will cause a jump to processor virtual address 0000.0001C. All other interrupts will
generate a standard interrupt request (IRQ), this will cause a jump to processor virtual address 0000.00018. Setting
the appropriate bit in this register enables the corresponding interrupt. All bits are cleared by a system reset. Please
refer to Section 3.6, “Interrupt Registers” for individual bit details.
90
DS502PP2
CS89712
3.6.3
INTSR2 Interrupt Status Register 2 (address 0x8000.1240)
15:14
13
12
11:3
2
1
0
Reserved
URXINT2
UTXINT2
Reserved
SS2TX
SS2RX
KBDINT
This register is an extension of INTSR1, containing status bits for backward compatibility with CL-PS7111. The interrupt status register also reflects the current state of the new interrupt sources within the CS89712. Each bit is set
if the appropriate interrupt is active. The interrupt assignment is given in Table 43.
Bit
Description
0
KBDINT: Keyboard interrupt. This interrupt is generated whenever a key is pressed, from the logical OR of the first 6 or all 8 of the Port A inputs (depending on the state of the KBD6 bit in the
SYSCON2 register. The interrupt request is latched and can be de-asserted by writing to the
KBDEOI location.
Note: KBDINT is not deglitched.
1
SS2RX: Synchronous serial interface 2 receives FIFO half or greater full interrupt. This is generated when RX FIFO contains 8 or more half-words. This interrupt is cleared only when the RX
FIFO is emptied or one SSI2 clock after RX is disabled.
2
SS2TX: Synchronous serial interface 2 transmit FIFO less than half empty interrupt. This is generated when TX FIFO contains fewer than 8 byte pairs. This interrupt gets cleared by loading the
FIFO with more data or disabling the TX. One synchronization clock required when disabling the
TX side before it takes effect.
12
UTXINT2: UART2 transmit FIFO half empty interrupt. The function of this interrupt source
depends on whether the UART2 FIFO is enabled. If the FIFO is disabled (FIFOEN bit is clear in
the UART2 bit rate and line control register), this interrupt will be active when there is no data in
the UART2 TX data holding register and be cleared by writing to the UART2 data register. If the
FIFO is enabled, this interrupt will be active when the UART2 TX FIFO is half or more empty and
is cleared by filling the FIFO to at least half full.
13
URXINT2: UART2 receive FIFO half full interrupt. The function of this interrupt source depends
on whether the UART2 FIFO is enabled. If the FIFO is disabled, this interrupt will be active when
there is valid RX data in the UART2 RX data holding register and be cleared by reading this data.
If the FIFO is enabled, this interrupt will be active when the UART2 RX FIFO is half or more full or
if the FIFO is non-empty, and no more characters have been received for a three-character timeout period, t is cleared by reading all the data from the RX FIFO.
Table 43. INSTR2
3.6.4
INTMR2 Interrupt Mask Register 2 (address 0x8000.1280)
15:14
13
12
11:3
2
1
0
Reserved
URXINT2
UTXINT2
Reserved
SS2TX
SS2RX
KBDINT
This register is an extension of INTMR1, containing interrupt mask bits for the backward compatibility with the CLPS7111. Please refer to INTSR2 for individual bit details.
DS502PP2
91
CS89712
3.6.5
INTSR3 Interrupt Status Register 3 (address 0x8000.2240)
7:1
0
Reserved
DAIPINT
This register is an extension of INTSR1 and INTSR2 containing status bits for the new features of the CS89712.
Each bit is set if the appropriate interrupt is active. The interrupt assignment is given in Table 44.
Bit
0
Description
DAIINT: DAI interface interrupt. The cause must be determined by reading the DAI status register. It is mapped to the FIQ interrupt on the ARM720T processor
Table 44. INTSR3
3.6.6
INTMR3 Interrupt Mask Register 3 (address 0x8000.2280)
7:1
0
Reserved
DAIINT
This register is an extension of INTMR1 and INTMR2, containing interrupt mask bits for the new features of the
CS89712. Please refer to INTSR3 for individual bit details.
3.7 Expansion Memory Configuration Registers
3.7.1
MEMCFG1 Memory Configuration Register 1 (address 0x8000.0180)
31:24
nCS[3] configuration
23:16
nCS[2] configuration
15:8
nCS[1] configuration
7:0
nCS[0] configuration
Expansion and ROM space is selected by one of eight chip selects. One of the chip selects (nCS[6]) is used internally for the on-chip SRAM, and the configuration is hardwired for 32-bit-wide, minimum- wait-state operation.
nCS[7] is used for the on-chip Boot ROM and the configuration field is hardwired for 8-bit-wide, minimum-wait-state
operation. Data written to the configuration fields for either nCS[6] or nCS7 will be ignored. Two of the chip selects
(nCS[4:5]) can be used to access two CL-PS6700 PC CARD controller devices, and when either of these interfaces
is enabled, the configuration field for the appropriate chip select in the MEMCFG2 register is ignored. When the PC
CARD1 or 2 control bit in the SYSCON2 register is disabled, then nCS[4] and nCS[5] are active as normal and can
be programmed using the relevant fields of MEMCFG2, as for the other four chip selects. All of the six external chip
selects are active for 256 Mbytes and the timing and bus transfer width can be programmed individually. This is accomplished by programming the six-byte-wide fields contained in two 32-bit registers, MEMCFG1 and MEMCFG2.
All bits in these registers are cleared by a system reset (except for the nCS[6] and nCS[7] configurations).
The Memory Configuration Register 1 is a 32-bit read / write register which sets the configuration of the four expansion and ROM selects nCS[0:3]. Each select is configured with a 1-byte field starting with expansion select 0.
92
DS502PP2
CS89712
3.7.2
MEMCFG2 Memory Configuration Register 2 (address 0x8000.01C0)
31:24
(Boot ROM)
7
CLKENB
23:16
(Local SRAM)
6
SQAEN
15:8
nCS[5] configuration
5:2
Wait States Field
7:0
nCS[4] configuration
1:0
Bus width
The Memory Configuration Register 2 is a 32-bit read / write register which sets the configuration of the two expansion and ROM selects nCS[4:5]. Each select is configured with a 1-byte field starting with expansion select 4.
Each of the six non-reserved byte fields for chip select configuration in the memory configuration registers are identical and define the number of wait states, the bus width, enable EXPCLK output during accesses and enable sequential mode access. This byte field is defined below. This arrangement applies to nCS[0:3], and nCS[4:5] when
the PC CARD enable bits in the SYSCON2 register are not set. The state of these bits is ignored for the Boot ROM
and local SRAM fields in the MEMCFG2 register.
Table 45 defines the bus width field. Note that the effect of this field is dependent on the two BOOTBIT bits that can
be read in the SYSFLG1 register. All bits in the memory configuration register are cleared by a system reset, and
the state of the BOOTBIT bits are determined by Port E bits 0 and 1 on the CS89712 during power-on reset. The
state of PE[1] and PE[0] determine whether the CS89712 is going to boot from either 32-bit-wide, 16-bit-wide or 8bit-wide ROMs.
Table 46 shows the values for the wait states for random and sequential wait states at 18 MHz bus. At 36 MHz bus
rate, the encoding becomes more complex. Table 47 preserves compatibility with the previous devices, while allowing the previously unused bit combinations to specify more variations of random and sequential wait states.
Bus Width Field
BOOTBIT1
BOOTBIT0
Expansion Transfer Mode
00
01
10
11
00
01
10
11
00
01
10
11
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
32-bit wide bus access
16-bit wide bus access
8-bit wide bus access
Reserved
8-bit wide bus access
Reserved
32-bit wide bus access
16-bit wide bus access
16-bit wide bus access
32-bit wide bus access
Reserved
8-bit wide bus access
Port E bits 1,0 during
NPOR reset
Low, Low
Low, Low
Low, Low
Low, Low
Low, High
Low, High
Low, High
Low, High
High, Low
High, Low
High, Low
High, Low
Table 45. Values of the Bus Width Field
Note: See AC Characteristics for more detail on bus timing.
The memory area decoded by CS[6] is reserved for the on-chip SRAM, hence this does not require a configuration
field in MEMCFG2. It is automatically set up for 32-bit-wide, no-wait-state accesses. For the Boot ROM, it is automatically set up for 8-bit, no wait state accesses.
Chip selects nCS[4] and nCS[5] are used to select two CL-PS6700 PC CARD controller devices. These have a multiplexed 16-bit wide address / data interface, and the configuration bytes in the MEMCFG2 register have no meaning
when these interfaces are enabled.
DS502PP2
93
CS89712
Value
No. of Wait States
Random
No. of Wait States
Sequential
00
4
3
01
3
2
10
2
1
11
1
0
Table 46. Values of the Wait State Field at 18 MHz
Bit 3
Bit 2
Bit 1
Bit 0
Wait States
Random
Wait States
Sequential
0
0
0
0
8
3
0
0
0
1
7
3
0
0
1
0
6
3
0
0
1
1
5
3
0
1
0
0
4
2
0
1
0
1
3
2
0
1
1
0
2
2
0
1
1
1
1
2
1
0
0
0
8
1
1
0
0
1
7
1
1
0
1
0
6
1
1
0
1
1
5
1
1
1
0
0
4
0
1
1
0
1
3
0
1
1
1
0
2
0
1
1
1
1
1
0
Table 47. Values of the Wait State Field at 36 MHz
Bit
6
7
Description
SQAEN: Sequential access enable. Setting this bit will enable sequential accesses that are on a
quad word boundary to take advantage of faster access times from devices that support page
mode. The sequential access will be faulted after four words (to allow video refresh cycles to
occur), even if the access is part of a longer sequential access. In addition, when this bit is not
set, non-sequential accesses will have a single idle cycle inserted at least every four cycles so
that the chip select is de-asserted periodically between accesses for easier debug.
CLKENB: Expansion clock enable. Setting this bit enables the EXPCLK to be active during
accesses to the selected expansion device. This will provide a timing reference for devices that
need to extend bus cycles using the EXPRDY input. Back-to-back (but not necessarily page
mode) accesses will result in a continuous clock.
Table 48. MEMCFG
94
DS502PP2
CS89712
3.8 Timer / Counter Registers
3.8.1
TC1D Timer Counter 1 Data Register (address 0x8000.0300)
The timer counter 1 data register is a 16-bit read / write register which sets and reads data to TC1. Any value
written will be decremented on the next rising edge of the clock.
3.8.2
TC2D Timer Counter 2 Data Register (address 0x8000.0340)
The timer counter 2 data register is a 16-bit read / write register which sets and reads data to TC2. Any value
written will be decremented on the next rising edge of the clock.
3.8.3
RTCDR Real-Time Clock Data Register (address 0x8000.0380)
The Real-Time Clock data register is a 32-bit read / write register, which sets and reads the binary time in
the RTC. Any value written will be incremented on the next rising edge of the 1 Hz clock. This register is
reset only by nPOR.
3.8.4
RTCMR Real-Time Clock Match Register (address 0x8000.03C0)
The Real-Time Clock match register is a 32-bit read / write register, which sets and reads the binary match
time to RTC. Any value written will be compared to the current binary time in the RTC, if they match it will
assert the RTCMI interrupt source. This register is reset only by nPOR.
3.9 Miscellaneous Registers
3.9.1
LEDFLSH Register (address 0x8000.22C0)
6
5:2
1:0
Enable
Duty ratio
Flash rate
The output is enabled whenever LEDFLSH[6] = 1. When enabled, PDDDR[0] needs to be configured as an output
pin and the bit cleared to ‘0’ (See Section 3.4.6, “PDDDR Port D Data Direction Register (address 0x8000.0043)”).
When the LED Flasher is disabled, the pin defaults to being used as Port D bit 0. Thus, this will ensure that the LED
will be off when disabled.
The flash rate is determined by the LEDFLSH[1:0] bits, in the following way:
LEDFLSH[1:0]
Flash Period (sec)
00
1
01
2
10
3
11
4
Table 49. LED Flash Rates
LEDFLSH[5:2]
Duty Ratio
(time on: time off)
LEDFLSH[5:2]
Duty Ratio
(time on: time off)
0000
01:15
1000
09:07
0001
02:14
1001
10:06
0010
03:13
1010
11:05
Table 50. LED Duty Ratio
DS502PP2
95
CS89712
LEDFLSH[5:2]
Duty Ratio
(time on: time off)
LEDFLSH[5:2]
Duty Ratio
(time on: time off)
0011
04:12
1011
12:04
0100
05:11
1100
13:03
0101
06:10
1101
14:02
0110
07:09
1110
15:01
0111
08:08
1111
16:00 (continually on)
Table 50. LED Duty Ratio (Continued)
3.9.2
SDCONF SDRAM Control Register (address 0x8000.2300)
31:11
10
9
8:7
6:5
4:2
1:0
Reserved
SDACTIVE
CLKCTL
SDWIDTH
SDSIZE
Reserved
CASLAT
Bit
Description
1:0.
How many clock cycles after CAS before the device is ready for reading or writing. . . ‘00’ =>
Reserved. . . , ‘01’ => Reserved, ‘10’ => CAS Latency = 2, ‘11’ => CAS Latency = 3. . . . . . . . . . .
The default value is ‘10’ for CAS latency = 2.
4:2.
Reserved.
6:5.
The capacity of each SDRAM. The values are: ‘00’=>16Mits, ‘01’=>64Mbits, ‘10’=>128Mbits,
‘11’=>256Mbits.
8:7.
The width of each SDRAM. ‘00’=>4bits, ‘01’=>8bits, ‘10’=>16 bits, ‘11’=>32 bits.
9.
Control over the SDRAM clock. ‘0’=> SDRAM clock is permanently enabled except when in
standby mode. ‘1’=>SDRAM clock stops when the CS89712 is put into inactive mode i.e.,
SDACTIVE = ‘0’, or when in standby mode.
10.
Enables the SDRAM controller: ‘0’ disables, ‘1’ enables. The SDRAM controller will only initialize
if SDACTIVE is set to 1. After initialization, resetting this parameter will cause the SDRAM controller to enter an inactive state. It will remain in this state until SDACTIVE is set to 1.
31:11.
Reserved.
3.9.3
SDRFPR SDRAM Refresh Period Register (address 0x8000.2340)
31:16
15:0
Reserved
REFRATE
This 16-bit read/write register sets the interval between SDRAM refresh commands. The value programmed is the
interval in BLCK cycles e.g. for a 16
µs refresh period with a BCLK of 36 MHz, the following value should be used:
16x10-6 * 36x106 = 576
The refresh timer is set to 256 by nPOR to ensure a refresh time of better than 16
programmed to a value below 2 otherwise the internal bus may become locked.
µs. This register should not be
This register replaces DPFPR, which is no longer active. Writes to this register are ignored. Reads from this register
will produce unpredictable results.
96
DS502PP2
CS89712
3.9.4
PMPCON Pump Control Register (address 0x8000.0400)
11:8
7:4
3:0
Drive 1 pump ratio
Drive 0 from AC source ratio
Drive 0 from battery ratio
The Pulse Width Modulator (PWM) pump control register is a 16-bit read / write register which sets and controls the
variable mark space ratio drives for the two PWMs. All bits in this register are cleared by a system reset. (The top
four bits are unused. They should be written as zeroes, and will read as undefined).
The state of the output drive pins is latched during power on reset, this latched value is used to determine the polarity
of the drive output. The sense of the PWM control lines is summarized in Table 51.
Initial State of Drive 0 or
Drive 1 During Power on Reset
Sense of Drive 0
or Drive 1
Polarity of Bias
Voltage
Low
Active high
+ve
High
Active low
-ve
Table 51. Sense of PWM control lines
External input pins that would normally be connected to the output from comparators monitoring the PWM output
are also used to enable these clocks. These are the FB[0:1] pins. When FB[0] is high, the PWM is disabled. The
same applies to FB[1]. They are read upon power-up.
Note:
To maximize power savings, the drive ratio fields should be used to disable the PWMs, instead of the FB
pins. The clocks that source the PWMs are disabled when the drive ratio fields are zeroed.4.
Bit
Description
0:3
Drive 0 from battery: This 4-bit field controls the “on” time for the Drive 0 PWM pump while the
system is powered from batteries. Setting these bits to 0 disables this pump, while setting these
bits to 1 allows the pump to be driven in a 1:16 duty ratio, 2 in a 2:16 duty ratio etc. up to a 15:16
duty ratio. An 8:16 duty ratio results in a square wave of 96 kHz when operating with an
18.432 MHz master clock.
4:7
Drive 0 from AC: This 4-bit field controls the “on” time for the Drive 0 DC to DC pump, while the
system is powered from a non-battery type power source. Setting these bits to 0 disables this
pump, setting these bits to 1 allows the pump to be driven in a 1:16 duty ratio, 2 in a 2:16 duty
ratio, etc. up to a 15:16 duty ratio. An 8:16 duty ratio results in a square wave of 96 kHz when
operating with an 18.432 MHz master clock.
Note: The CS89712 monitors the power supply input pins (i.e., BATOK and NEXTPWR) to
determine which of the above fields to use.
8:11
Drive 1 pump ratio: This 4-bit field controls the “on” time for the drive1 PWM pump. Setting
these bits to 0 disables this pump, while setting these bits to 1 allows the pump to be driven in a
1:16 duty ratio, 2 in a 2:16 duty ratio, etc. up to a 15:16 duty ratio. An 8:16 duty ratio results in a
square wave of 96 kHz when operating with an 18.432 MHz master clock.
Table 52. PMPCON
3.9.5
CODR — The CODEC Interface Data Register (address 0x8000.0440)
The CODR register is an 8-bit read / write register, to be used with the codec interface. This is selected by
the appropriate setting of bit 0 (SERSEL) of the SYSCON2 register. Data written to or read from this register
is pushed or popped onto the appropriate 16-byte FIFO buffer. Data from this buffer is then serialized and
sent to or received from the codec sound device. When the codec is enabled, the codec interrupt CSINT is
DS502PP2
97
CS89712
generated repetitively at 1/8th the byte transfer rate and the FIFO state can be read in the system flags register. The net data transfer rate to / from the codec device is 8 kBytes/s, giving an interrupt rate of 1 kHz.
3.9.6
STFCLR Clear all “Start Up Reason” Flags Location (address 0x8000.05C0)
A write to this location will clear all the “Start Up Reason” flags in the system flags status register SYSFLG.
The ‘Start Up Reason’ flags should first read to determine the reason why the chip was started (i.e., a new
battery was installed). Any value may be written to this location.
3.10 UART Registers
3.10.1 UARTDR1–2, UART1–2 Data Registers (address 0x8000.0480 and 0x8000.1480)
10
9
8
7:0
OVERR
PARERR
FRMERR
RX data
The UARTDR registers are 11-bit read and 8-bit write registers for all data transfers to or from the internal UARTs
1 and 2.
Data written to these registers is pushed onto the 16-byte data TX holding FIFO if the FIFO is enabled. If not it is
stored in a one byte holding register. This write will initiate transmission from the UART.
The UART data read registers are made up of the 8-bit data byte received from the UART together with three bits
of error status. If the FIFO is enabled, data read from this register is popped from the 16 byte data RX FIFO. If the
FIFO is not enabled, it is read from a one byte buffer register containing the last byte received by the UART. If it is
enabled, data received and error status is automatically pushed onto the RX FIFO. The RX FIFO is 10-bits wide by
16 deep.
Note:
These registers should be accessed as words.
Bit
Description
8
FRMERR: UART framing error. This bit is set if the UART detected a framing error while receiving the associated data byte. Framing errors are caused by non-matching word lengths or bit
rates.
9
PARERR: UART parity error. This bit is set if the UART detected a parity error while receiving the
data byte.
10
OVERR: UART over-run error. This bit is set if more data is received by the UART and the FIFO
is full. The overrun error bit is not associated with any single character and so is not stored in the
FIFO. If this bit is set, the entire contents of the FIFO is invalid and should be cleared. This error
bit is cleared by reading the UARTDR register.
Table 53. UARTDR1-2 UART1-2
98
DS502PP2
CS89712
3.10.2 UBRLCR1–2 UART1–2 Bit Rate and Line Control Registers
(address 0x8000.04C0 and 0x8000.14C0)
31:19
18:17
16
15
14
13
12
11:0
WRDLEN
FIFOEN
XSTOP
EVENPRT
PRTEN
BREAK
Bit rate divisor
The bit rate divisor and line control register is a 19-bit read / write register. Writing to these registers sets the bit rate
and mode of operation for the internal UARTs.
Bit
0:11
Description
Bit rate divisor: This 12-bit field sets the bit rate. If the system is operating from the PLL clock,
then the bit rate divider is fed by a clock frequency of 3.6864 MHz, which is then further divided
internally by 16 to give the bit rate. The formula to give the divisor value for any bit rate when
operating from the PLL clock is: Divisor = 230400 / (bit rate divisor + 1). A value of zero in this
field is illegal when running from the PLL clock. The tables below show some example bit rates
with the corresponding divisor value.The table below shows the bit rates available for 18.432 MHz
operation.
Divisor Value
0
1
2
3
5
11
15
23
95
191
2094
Bit Rate Running
From the PLL Clock
—
115200
76800
57600
38400
19200
14400
9600
2400
1200
110
12
BREAK: Setting this bit will drive the TX output active (high) to generate a break.
13
PRTEN: Parity enable bit. Setting this bit enables parity detection and generation
14
EVENPRT: Even parity bit. Setting this bit sets parity generation and checking to even parity,
clearing it sets odd parity. This bit has no effect if the PRTEN bit is clear.
15
XSTOP: Extra stop bit. Setting this bit will cause the UART to transmit two stop bits after each
data byte, while clearing it will transmit one stop bit after each data byte.
16
FIFOEN: Set to enable FIFO buffering of RX and TX data. Clear to disable the FIFO (i.e., set its
depth to one byte).
DS502PP2
99
CS89712
Bit
17:18
Description
WRDLEN: This two bit field selects the word length according to the table below.
WRDLEN
00
01
10
11
Word Length
5 bits
6 bits
7 bits
8 bits
Table 54. UBRLCR1-2 UART1-2 (Continued)
3.11 LCD Registers
3.11.1
LCDCON — The LCD Control Register (address 0x8000.02C0)
31
30
29:25
24:19
18:13
12:0
GSMD2
GSMD1
AC prescale
Pixel prescale
Line length
Video buffer size
The LCD control register is a 32-bit read / write register that controls the size of the LCD screen and the operating
mode of the LCD controller. Refer to the system description of the LCD controller for more information on video buffer mapping, and for details of how to program the LCD control register for use in Snooze State.
The LCDCON register should only be reprogrammed when the LCD controller is disabled.
Bit
Description
0:12
Video buffer size: The video buffer size field is a 13-bit field that sets the total number of bits x
128 (quad words) in the video display buffer. This is calculated from the formula:
Video buffer size = (Total bits in video buffer / 128) – 1
i.e., for a 640 x 240 LCD and 4 bits-per-pixel, the size of the video buffer is equal to
614400 bits.
Video buffer = 640 x 240 x 4=614400 bits
Video buffer size field = (614400 / 128) – 1 = 4799 or 0x12BF hex.
If Snooze State is to be used with the LCD controller enabled, then the value programmed into
this register should not be less than 3. The minimum value allowed is 3 for this bit field.
13:18
Line length: The line length field is a 6-bit field that sets the number of pixels in one complete
line. This field is calculated from the formula:
line length = (Number of pixels in line / 16) – 1
i.e., for 640 x 240 LCD Line length = (640 / 16) – 1 = 39 or 0x27 hex.
The minimum value that can be programmed into this register is a 1 (i.e., 0 is not a legal value).
Table 55. LCDCON
100
DS502PP2
CS89712
Bit
19:24
Description
Pixel prescale: The pixel prescale field is a 6-bit field that sets the pixel rate prescale. The pixel
rate is always derived from a 36.864 MHz clock and is calculated from the formula:
Pixel rate (MHz) = 36.864 / (Pixel prescale + 1)
The pixel prescale value can be expressed in terms of the LCD size by the formula:
When the CS89712 is operating @ 18.432 MHz:
Pixel prescale = (36864000 / (Refresh Rate x Total pixels in display)) – 1
Refresh Rate is the screen refresh frequency (70 Hz to avoid flicker)
The value should be rounded down to the nearest whole number and zero is illegal and will result
in no pixel clock.
EXAMPLE: For a system being operated in the 18.432–73.728 MHz mode, with a 640 x 240
screen size, and 70 Hz screen refresh rate desired, the LCD Pixel prescale equals 36.864E6 /
(70 x 640x240) – 1 = 2.428
Rounding 2.428 down to the nearest whole number equals 2.
This gives an actual pixel rate of 36.864E6 / (2+1) = 12.288 MHz, which gives an actual refresh
frequency of 12.288E6 / (640x240) = 80 Hz.
Note: As the CL[2] low pulse time is doubled after every CL[1] high pulse this refresh frequency
is only an approximation, the accurate formula is 12.288E6 / ((640x240)+120) = 79.937 Hz.
25:29
AC prescale: The AC prescale field is a 5-bit number that sets the LCD AC bias frequency. This
frequency is the required AC bias frequency for a given manufacturer’s LCD plate. This frequency is derived from the frequency of the line clock (CL[1]). The LCD M signal will toggle after
n+1 counts of the line clock (CL[1]) where n is the number programmed into the AC prescale
field. This number must be chosen to match the manufacturer’s recommendation. This is normally 13, but must not be exactly divisible by the number of lines in the display.
30
GSMD1: Grayscale mode bit number 1. Setting this bit enables 2 or 4 bits-per-pixel (01 or 11,
respectively) grayscaling. (Also see the GSMD2 bit definition.) Clearing this bit enables 1 bpp
(00) gray scaling only. Note: Gray scaling is always enabled when using the EP72xx LCD Controller. Direct mapping of the frame buffer bits to the LCD display is not supported. However, this
can be accomplished by simply programming the palette register contents to correspond with the
frame buffer bit value (i.e., for 1 bpp (00) Direct mapping program the PALLSW register nibble
[3:0] with zeros, and nibble [7:4] with ones.)
31
GSMD2: Grayscale mode bit number 2. Setting this bit enables 4 bpp (11) gray scaling (15 gray
scales.) Clearing this bit enables 2 bits-per-pixel (01) gray scaling.
Table 55. LCDCON (Continued)
DS502PP2
101
CS89712
3.11.2
PALLSW Least Significant Word — LCD Palette Register (address 0x8000.0580)
31:28
Grayscale
value for pixel
value 7
27:24
23:20
19:16
15:12
11:8
7:4
3:0
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
value for pixel value for pixel value for pixel value for pixel value for pixel value for pixel value for pixel
value 6
value 5
value 4
value 3
value 2
value 1
value 0
The least and most significant word LCD palette registers make up a 64-bit read / write register which maps the logical pixel value to a physical grayscale level. The 64-bit register is made up of 16 x 4-bit nibbles, each nibble defines
the grayscale level associated with the appropriate pixel value. If the LCD controller is operating in two bits-per-pixel,
only the lower 4 nibbles are valid (D[15:0] in the least significant word). Similarly, one bit-per-pixel means only the
lower 2 nibbles are valid (D[7:0]) in the least significant word.
3.11.3
PALMSW Most Significant Word — LCD Palette Register (address 0x8000.0540)
31:28
Grayscale
value for pixel
value 15
27:24
23:20
19:16
15:12
11:8
7:4
3:0
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
Grayscale
value for pixel value for pixel value for pixel value for pixel value for pixel value for pixel value for pixel
value 14
value 13
value 12
value 11
value 10
value 9
value 8
The pixel to grayscale level assignments and the actual physical color and pixel duty ratio for the grayscale values
are shown in Table 56. Note that colors 8–15 are the inverse of colors 7–0 respectively. This means that colors 7
and 8 are identical. Therefore, in reality only 15 grayscales available, not 16. The steps in the grayscale are nonlinear, but have been chosen to give a close approximation to perceived linear grayscales. The is due to the eye
being more sensitive to changes in gray level close to 50% gray (See PALLSW description).
Grayscale Value
Duty Cycle
% Pixels Lit
% Step Change
0
0
0%
11.1%
1
1/9
11.1%
8.9%
2
1/5
20.0%
6.7%
3
4/15
26.7%
6.6%
4
3/9
33.3%
6.7%
5
2/5
40.0%
5.4%
6
4/9
44.4%
5.6%
7
1/2
50.0%
0.0%
8
1/2
50.0%
5.6%
9
5/9
55.6%
5.4%
10
3/5
60.0%
6.7%
11
6/9
66.7%
6.6%
12
11/15
73.3%
6.7%
13
4/5
80.0%
8.9%
14
8/9
88.9%
11.1%
15
1
100%
Table 56. Grayscale Value to Color Mapping
102
DS502PP2
CS89712
3.11.4
FBADDR LCD Frame Buffer Start Address (address 0x8000.1000)
This register contains the start address for the LCD Frame Buffer. It is assumed that the frame buffer starts at location 0x0000000 within each chip select memory region. Therefore, the value stored within the FBADDR register is
only the value of the chip select where the frame buffer is located. On reset, this will be set to 0xC. The register is 4
bits wide (bits [3:0]). This register must only be reprogrammed when the LCD is disabled (i.e., setting the LCDEN
bit within SYSCON2 low), or during the period after exit from Snooze State before the LCDSNZE bit has been reset
(i.e. while data is still being displayed from the on-chip SRAM in 1 bit per pixel mode).
3.12 SSI Register
3.12.1 SYNCIO Synchronous Serial ADC Interface Data Register (address 0x8000.0500)
In the default mode, the bits in SYNCIO have the following meaning:
31:15
14
13
12:8
7:0
Reserved
TXFRMEN
SMCKEN
Frame length
ADC Configuration Byte
Whereas in extended mode, the following applies:
15
14
13
12:7
6:0
Reserved
TXFRMEN
SMCKEN
Frame length
ADC Configuration Length
Note:
The frame length in extended mode is 6 bits wide to allow up to 16 write bits, 1 null bit and 16 read bits (=
33 cycles).
SYNCIO is a 32-bit read / write register. The data written to the SYNCIO register configures the master only SSI. In
default mode, the least significant byte is serialized and transmitted out of the synchronous serial interface1 (i.e.,
SSI1) to configure an external ADC, MSB first. In extended mode, a variable number of bits are sent from SYNCIO[16:31] as determined by the ADC Configuration Length. The transfer clock will automatically be started at the
programmed frequency and a synchronization pulse will be issued. The ADCIN pin is sampled on every positive going clock edge (or the falling clock edge, if ADCCKNSEN in SYSCON3 is set) and the result is shifted in to the SYNCIO read register.
During data transfer, the SSIBUSY bit is set high; at the end of a transfer the SSEOTI interrupt will be asserted. To
clear the interrupt the SYNCIO register must be read. The data read from the SYNCIO register is the last sixteen
bits shifted out of the ADC.
The length of the data frame can be programmed by writing to the SYNCIO register. This allows many different ADCs
to be accommodated. The device is SPI- / Microwire-compatible (transfers are in multiples of 8 bits). However, to be
compatible with some non-SPI / Microwire devices, the data written to the ADC device can be anything between 8
to 16 bits. This is user-definable per the ADC Configuration Extension section of the SYNCIO register.
Bit
0:7 or 0:6
Description
ADC Configuration Byte: When the ADCCON control bit in the SYSCON3 register = 0, this is
the 8-bit configuration data to be sent to the ADC. When the ADCCON control bit in the
SYSCON3 register = 1, this field determines the length of the ADC configuration data held in the
ADC Configuration Extension field for sending to the ADC.
Table 57. SYNCIO
DS502PP2
103
CS89712
Bit
Description
8:12 or 7:12
Frame length: The Frame Length field is the total number of shift clocks required to complete a
data transfer.
In default mode, MAX148/9 (and for many ADCs), this is 25 = (8 for configuration byte + 1 null bit
+ 16 bits result).
In extended mode, AD7811/12, this is 23 = (10 for configuration byte + 3 null + 10 bits result).
13
SMCKEN: Setting this bit will enable a free running sample clock at twice the programmed ADC
clock frequency to be output on the SMPLCK pin.
14
TXFRMEN: Setting this bit will cause an ADC data transfer to be initiated. The value in the ADC
configuration field will be shifted out to the ADC and depending on the frame length programmed,
a number of bits will be captured from the ADC. If the SYNCIO register is written to with the
TXFRMEN bit low, no ADC transfer will take place, but the Frame length and SMCKEN bits will
be affected.
16:31
ADC Configuration Extension: When the ADCCON control bit in the SYSCON3 register = 0,
this field is ignored for compatibility with the CL-PS7111. When the ADCCON control bit in the
SYSCON3 register = 1, this field is the configuration data to be sent to the ADC. The ADC Configuration Extension field length is determined by the value held in the ADC Configuration Length
field (SYNCIO[6:0]).
Table 57. SYNCIO (Continued)
3.13 End Of Interrupt Locations
The ‘End of Interrupt’ locations that follow are written to after the appropriate interrupt has been serviced.
The write is performed to clear the interrupt status bit, so that other interrupts can be serviced. Any value
may be written to these locations.
3.13.1 BLEOI Battery Low End of Interrupt (address 0x8000.0600)
A write to this location clears the interrupt generated by a low battery (falling edge of BATOK with nEXTPWR
high).
3.13.2 MCEOI Media Changed End of Interrupt (address 0x8000.0640)
A write to this location will clear the interrupt generated by a falling edge of the nMEDCHG input pin.
3.13.3 TEOI Tick End of Interrupt Location (address 0x8000.0680)
A write to this location will clear the current pending tick interrupt and tick watch dog interrupt.
3.13.4 TC1EOI TC1 End of Interrupt Location (address 0x8000.06C0)
A write to this location will clear the under flow interrupt generated by TC1.
3.13.5 TC2EOI TC2 End of Interrupt Location (address 0x8000.0700)
A write to this location will clear the under flow interrupt generated by TC2.
3.13.6 RTCEOI RTC Match End of Interrupt (address 0x8000.0740)
A write to this location will clear the RTC match interrupt
3.13.7 UMSEOI UART1 Modem Status Changed End of Interrupt (address 0x8000.0780)
A write to this location will clear the modem status changed interrupt.
104
DS502PP2
CS89712
3.13.8 COEOI Codec End of Interrupt Location (address 0x8000.07C0)
A write to this location clears the sound interrupt (CSINT).
3.13.9 KBDEOI Keyboard End of Interrupt Location (address 0x8000.1700)
A write to this location clears the KBDINT keyboard interrupt.
3.13.10 SRXEOF End of Interrupt Location (address 0x8000.1600)
A write to this location clears the SSI2 RX FIFO overflow status bit.
3.14 State Control Registers
3.14.1 STDBY Enter the Standby State Location (address 0x8000.0840)
A write to this location will put the system into the Standby State by halting the main oscillator. A write to this
location while there is an active interrupt will have no effect.
Notes: 1. Before entering the Standby State, the LCD Controller should be disabled. The LCD controller
should be enabled on exit from the Standby State.
2. If the CS89712 is attempting to get into the Snooze/Standby State when there is a pending
interrupt request, it will not enter into the low power mode. The instruction will get executed, but
the processor will ignore the command.
3.14.2 SNOOZE Enter Snooze State location
A write to this location will put the system into the Snooze State. The main clock will not be stopped in this
state. It is required to continue displaying a reduced LCD buffer on the first few lines of the display, and the
DC pump block will continue to generate the drive signals for external DC converter circuitry. Otherwise,
clocks to all parts of the device will be disabled. The device will automatically switch the DRAMs into self
refresh if the RFSHEN bit is set in the DRAM refresh period register. All transitions to the Snooze State are
synchronized with DRAM cycles. A write to this location while there is an active interrupt will have no effect.
Before entering this state, the data to be displayed in Snooze State must be transferred under program control into the on-chip SRAM (see section on Snooze State), and the LCDCON register and frame buffer start
address must be reprogrammed accordingly. On exit from Snooze State (via enabled interrupt or wakeup
event) program execution will continue from the next instruction after the write to the SNOOZE location.
3.14.3 HALT Enter the Idle State Location (address 0x8000.0800)
A write to this location will put the system into the Idle State by halting the clock to the processor until an
interrupt is generated. A write to this location while there is an active interrupt will have no effect.
3.14.4 SNZDISP Snooze Mode Display Size
This register contains the number of words to be displayed from the on-chip SRAM in Snooze State, minus
1. It is a 13-bit register, allowing up to 816 K words to be displayed. Because the on-chip SRAM data is always displayed at 1-bit-per-pixel in the Snooze State, the value programmed into this register is the number
of pixels to be displayed divided by 32. For a half-size VGA screen the number of words to be programmed
is (640 x 240 x 1)/32 = 4.8 K words. This is the maximum value that should be programmed in this register
in Snooze State for a half-size VGA display. To avoid any possibility of ‘snow’ on the display when operating
at high frequency, this register should always be programmed with a minimum value of 7. Correct operation
is not guaranteed below this value. The number of pixels displayed should be divisible by the number of
pixels in a single line of the display.
DS502PP2
105
CS89712
3.15 SS2 Registers
3.15.1 SS2DR Synchronous Serial Interface 2 Data (address 0x8000.1500)
This is the 16-bit-wide data register for the full-duplex master / slave SSI2 synchronous serial interface. Writing data to this register will initiate a transfer. Writes need to be word writes and the bottom 16 bits are transferred to the TX FIFO. Reads will be 32 bits as well with the lower 16 bits containing RX data, and the upper
16-bits should be ignored. Although the interface is byte-oriented, data is written in two bytes at a time to
allow higher bandwidth transfer. It is up to the software to assemble the bytes for the data stream in an appropriate manner.
All reads / writes to this register must be word reads / writes.
3.15.2 SS2POP Synchronous Serial Interface 2 Pop Residual Byte (address 0x8000.16C0)
This is a write-only location which will cause the contents of the RX shift register to be popped into the RX
FIFO, thus enabling a residual byte to be read. The data value written to this register is ignored. This location
should be used in conjunction with the RESVAL and RESFRM bits in the SYSFLG2 register.
3.16 DAI Registers
There are five registers within the DAI Interface; one control, three data, and one status register. The control
register is used to mask or unmask interrupt requests to service the DAI’s FIFOs, and to select whether an
on-chip or off-chip clock is used to drive the bit rate, and to enable / disable operation. The first pair of data
register addresses the top of the Right Channel Transmit FIFO and the bottom of the Right Channel Receive
FIFO. A read accesses the receive FIFOs, and a write the transmit FIFOs. Note that these are four physically separate FIFOs to allow full-duplex transmission. The status register contains bits which signal FIFO
overrun and underrun errors and transmit and receive FIFO service requests. Each of these status conditions signal an interrupt request to the interrupt controller. The status register also flags when the transmit
FIFOs are not full when the receive FIFOs are not empty.
106
DS502PP2
CS89712
3.16.1 DAI Control Register (address 0x8000.2000)
31-24
23
22
21
20
19
18
17
16
15-0
Reserved
Reserved
RCRM
RCTM
LCRM
LCTM
Reserved
ECS
DAIEN
Reserved
The DAI control register (DAIR) contains eight different bit fields that control various functions within
the DAI interface.
Bit
0-15
Description
Reserved Must be set to 0x0404
7
Reserved
15
Reserved
16
DAIEN: DAI Interface Enable
0 — DAI operation disabled, control of the SDIN, SDOUT, SCLKLRCK, and LRCK pins given to
the SSI2 / CODEC / DAI pin mulitiplexing logic to assign I/O pins 60-64 to another block.
1 — DAI operation enabled
Note that by default, the SSI / CODEC have precedence over the DAI interface in regard to the
use of the I/O pins. Nevertheless, when bit 3 (DAISEL) of register SYSCON3 is set to 1, then
the above mentioned DAI ports are connected to I/O pins 60–64.
17
ECS: External Clock Select selects external MCLK when = 1.
18
ReservedMust be 0.
19
LCTM: Left Channel Transmit FIFO Interrupt Mask
0 — Left Channel Transmit FIFO half-full or less condition does not generate an interrupt (LCTS
bit ignored).
1 — Left Channel Transmit FIFO half-full or less condition generates an interrupt (state of LCTS
sent to interrupt controller).
20
LCRM: Left Channel Receive FIFO Interrupt Mask
0 — Left Channel Receive FIFO half-full or more condition does not generate an interrupt
(LCRS bit ignored).
1 — Left Channel Receive FIFO half-full or more condition generates an interrupt (state of
LCRS sent to interrupt controller).
21
RCTM: Right Channel Transmit FIFO Interrupt Mask
0 — Right Channel Transmit FIFO half-full or less condition does not generate an interrupt
(RCTS bit ignored).
1 — Right Channel Transmit FIFO half-full or less condition generates an interrupt (state of
RCTS sent to interrupt controller).
22
RCRM: Right Channel Receive FIFO Interrupt Mask
0 — Right Channel Receive FIFO half-full or more condition does not generate an interrupt
(RCRS bit ignored).
1 — Right Channel Receive FIFO half-full or more condition generates an interrupt (state of
RCRS sent to interrupt controller).
23
Reserved
24-31
Reserved
Table 58. DAI Control Register
DS502PP2
107
CS89712
3.16.1.1 DAI Enable (DAIEN)
The DAI enable (DAIEN) bit is used to enable and disable all DAI operation.
When the DAI is disabled, all of its clocks are powered down to minimize power consumption. Note
that DAIEN is the only control bit within the DAI interface that is reset to a known state. It is cleared
to zero to ensure the DAI timing is disabled following a reset of the device.
When the DAI timing is enabled, SCLK begins to transition and the start of the first frame is signaled
by driving the LRCK pin low. The rising and falling-edge of LRCK coincides with the rising and fallingedge of SCLK. As long as the DAIEN bit is set, the DAI interface operates continuously, transmitting
and receiving 128 bit data frames. When the DAIEN bit is cleared, the DAI interface is disabled immediately, causing the current frame which is being transmitted to be terminated. Clearing DAIEN resets the DAI’s interface FIFOs. However DAI data register 3, the control register and the status
register are not reset. Therefore, the user must ensure these registers are properly reconfigured before re-enabling the DAI interface.
3.16.1.2 DAI Interrupt Generation
The DAI interface can generate four maskable interrupts and four non-maskable interrupts, as described in the sections below. Only one interrupt line is wired into the interrupt controller for the whole
DAI interface. This interrupt is the wired OR of all eight interrupts (after masking where appropriate).
The software servicing the interrupts must read the status register in the DAI to determine which
source(s) caused the interrupt. It is possible to prevent any DAI sources causing an interrupt by masking the DAI interrupt in the interrupt controller register.
3.16.1.3 Left Channel Transmit FIFO Interrupt Mask (LCTM)
The Left channel sample transmit FIFO interrupt mask (LCTM) bit is used to mask or enable the left
channel sample transmit FIFO service request interrupt. When LATM = 0, the interrupt is masked and
the state of the Left Channel Transmit FIFO service request (LCTS) bit within the DAI status register
is ignored by the interrupt controller. When LCTM = 1, the interrupt is enabled and whenever LCTS
is set (one) an interrupt request is made to the interrupt controller. Note that programming LCTM = 0
does not affect the current state of LCTS or the Left Channel Transmit FIFO logic’s ability to set and
clear LCTS; it only blocks the generation of the interrupt request.
3.16.1.4 Left Channel Receive FIFO Interrupt Mask (LARM)
The left channel sample receive FIFO interrupt mask (LCRM) bit is used to mask or enable the Left
Channel Receive FIFO service request interrupt. When LCRM = 0, the interrupt is masked and the
state of the left channel sample receive FIFO service request (LCRS) bit within the DAI status register
is ignored by the interrupt controller. When LCRM = 1, the interrupt is enabled and whenever LCRS
is set (one) an interrupt request is made to the interrupt controller. Note that programming LCRM = 0
does not affect the current state of LCRS or the Left Channel Receive FIFO logic’s ability to set and
clear LCRS, it only blocks the generation of the interrupt request.
3.16.1.5 Right Channel Transmit FIFO Interrupt Mask (RCTM)
The Right Channel Transmit FIFO interrupt mask (RCTM) bit is used to mask or enable the right channel transmit FIFO service request interrupt. When RCTM = 0, the interrupt is masked and the state of
the Right Channel Transmit FIFO service request (RCTS) bit within the DAI status register is ignored
by the interrupt controller. When RCTM = 1, the interrupt is enabled and whenever RCTS is set (one)
an interrupt request is made to the interrupt controller. Note that programming RCTM = 0 does not
affect the current state of RCTS or the Right Channel Transmit FIFO logic’s ability to set and clear
RCTS, for it only blocks the generation of the interrupt request.
108
DS502PP2
CS89712
3.16.1.6 Right Channel Receive FIFO Interrupt Mask (RCRM)
The Right Channel Receive FIFO interrupt mask (RCRM) bit is used to mask or enable the Right
Channel Receive FIFO service request interrupt. When RCRM = 0, the interrupt is masked and the
state of the Right Channel Receive FIFO service request (RCRS) bit within the DAI status register is
ignored by the interrupt controller. When RCRM = 1, the interrupt is enabled, and whenever RCRS is
set (one), an interrupt request is made to the interrupt controller. Note that programming RCRM = 0
does not affect the current state of RCRS or the Right Channel Receive FIFO logic’s ability to set and
clear RCRS, for it only blocks the generation of the interrupt request.
3.16.2 DAI Data Registers
The DAI contains three data registers: DAIDR0 addresses the top entry of the Right Channel Transmit
FIFO and bottom entry of the Right Channel Receive FIFO; DAIDR1 addresses the top and bottom entry
of the Left Channel Transmit and Receive FIFOs, respectively; and DAIDR2 is used to perform enable and
disable the DAI FIFOs.
3.16.3 DAIDR0 DAI Data Register 0 (address 0x8000.2040)
31-16
15-0
Reserved
Bottom of Right Channel Receive FIFO
Read Access
31-16
15-0
Reserved
Top of Right Channel Transmit FIFO
Write Access
When DAI Data Register 0 (DAIDR0) is read, the bottom entry of the Right Channel Receive FIFO is
accessed. As data is removed by the DAI’s receive logic from the incoming data frame, it is placed
into the top entry of the Right Channel Receive FIFO and is transferred down an entry at a time until
it reaches the last empty location within the FIFO. Data is removed by reading DAIDR0, which accesses the bottom entry of the right channel FIFO. After DAIDR0 is read, the bottom entry is invalidated, and all remaining values within the FIFO automatically transfer down one location.
When DAIDR0 is written, the top-most entry of the Right Channel Transmit FIFO is accessed. After a
write, data is automatically transferred down to the lowest location within the transmit FIFO which
does not already contain valid data. Data is removed from the bottom of the FIFO one value at a time
by the transmit logic, loaded into the correct position within the 64-bit transmit serial shifter, then serially shifted out onto the SDOUT pin.
Table 59 shows DAIDR0. Note that the Transmit and Receive Right Channel FIFOs are cleared when
the device is reset, or by writing a zero to DAIEN (DAI disabled). Also, note that writes to reserved
bits are ignored and reads return zeros.
Bit
0-15
DS502PP2
Description
RIGHT CHANNEL DATA: Transmit / Receive Right Channel FIFO Data
Read — Bottom of Right Channel Receive FIFO data
Write — Top of Right Channel Transmit FIFO data
109
CS89712
Bit
16-31
Description
Reserved
Table 59. DAI Data Register 0 (Continued)
3.16.4 DAIDR1 DAI Data Register 1 (address 0x8000.2080)
31-16
15-0
Reserved
Bottom of Left Channel Receive FIFO
Read Access
31-16
15-0
Reserved
Top of Left Channel Transmit FIFO
Write Access
When DAI Data Register 1 (DAIDR1) is read, the bottom entry of the Left Channel Receive FIFO is accessed. As
data is removed by the DAI’s receive logic from the incoming data frame, it is placed into the top entry of the Left
Channel Receive FIFO and is transferred down an entry at a time until it reaches the last empty location within the
FIFO. Data is removed by reading DAIDR1, which accesses the bottom entry of the left channel FIFO. After DAIDR1
is read, the bottom entry is invalidated, and all remaining values within the FIFO automatically transfer down one
location.
When DAIDR1 is written, the top-most entry of the Left Channel Transmit FIFO is accessed. After a write, data is
automatically transferred down to the lowest location within the transmit FIFO which does not already contain valid
data. Data is removed from the bottom of the FIFO one value at a time by the transmit logic. It is then loaded into
the correct position within the 64-bit transmit serial shifter then serially shifted out onto the SDOUT pin.
Table 60 shows DAIDR1. Note that the Transmit and Receive Left Channel FIFOs are cleared when the device is
reset, or by writing a zero to DAIEN (DAI disabled). Also, note that writes to reserved bits are ignored and reads
return zeros.
Bit
Description
0-15
LEFT CHANNEL DATA: Transmit / Receive Left Channel FIFO Data
Read — Bottom of Left Channel Receive FIFO data
Write — Top of Left Channel Transmit FIFO data
16-31
Reserved
Table 60. DAI Data Register 1
3.16.5 DAIDR2 DAI Data Register 2 (address 0x8000.20C0)
31-21
20-16
15
14-0
Reserved
FIFO Channel Select
FIFOEN
Reserved
DAIDR2 is a 32-bit register that utilizes 21 bits and is used to enable and disable the FIFOs for the
left and right channels of the DAI data stream. The left channel FIFO is enabled by writing
0x000D.8000 and disabled by writing 0x000D.0000. The right channel FIFO is enabled by writing
0x0011.8000 and disabled by writing 0x0011.0000. After writing a value to this register, wait until the
110
DS502PP2
CS89712
FIFO operation complete bit (FIFO) is set in the DAI status register before writing another value to this
register.
Bit
Description
0-14
Reserved
15
FIFOEN: FIFO Transmit Bit
0 — Disable Transmit
1 — Enable Transmit
16-20
FIFO CHANNEL SELECT:
01101b — Left channel select
10001b — Right channel select
21-31
Reserved
Table 61. DAI Data Register 2
3.16.6 DAISR DAI Status (address 0x8000.2100)
The DAI Status register (DAISR) contains bits which signal FIFO overrun and underrun errors and
FIFO service requests. Each of these conditions signal an interrupt request to the interrupt controller.
The status register also flags when transmit FIFOs are not full, when the receive FIFOs are not empty,
when a FIFO operation is complete, and when the right channel or left channel portion of the CODEC
is enabled (no interrupt generated).
Bits which cause an interrupt signal the interrupt request as long as the bit is set. Once the bit is
cleared, the interrupt is cleared. Read / write bits are called status bits, read-only bits are called flags.
Status bits are referred to as “sticky” (once set by hardware, they must be cleared by software). Writing a one to a sticky status bit clears it, while writing a zero has no effect. Read-only flags are set and
cleared by hardware, and writes have no effect. Additionally, some bits which cause interrupts have
corresponding mask bits in the control register and are indicated in the section headings below. Note
that the user has the ability to mask all DAI interrupts by clearing the DAI bit within the interrupt controller mask register INTMR3.
31-13
12
11
10
9
8
7
Reserved
FIFO
LCNE
LCNF
RCNE
RCNF
RCCELCRO
6
5
4
3
2
1
0
RCNFLCTU
LCRORCRO
LCTURCTU
LCRS
LCTS
LCRSRCRS
LCTSRCTS
Bit
Description
0
RCTS: Right Channel Transmit FIFO Service Request Flag (read-only)
0 — Right Channel Transmit FIFO is more than half full (five or more entries filled) or DAI disabled
1 — Right Channel Transmit FIFO is half full or less (four or fewer entries filled) and DAI operation is enabled, interrupt request signaled if not masked
(if RCTM = 1)
Table 62. DAI Control, Data and Status Register Locations
DS502PP2
111
CS89712
Bit
Description
1
RCRS: Right Channel Receive FIFO Service Request (read-only)
0 — Right Channel Receive FIFO is less than half full (five or fewer entries filled) or DAI disabled
1 — Right Channel Receive FIFO is half full or more (six or more entries filled) and DAI operation is enabled, interrupt request signaled if not masked (if RCRM = 1)
2
LCTS: Left Channel Transmit FIFO Service Request Flag (read-only)
0 — Left Channel Transmit FIFO is more than half full or less (four or fewer entries filled) or DAI
disabled.
1 — Left Channel Transmit FIFO is half full or less (four or fewer entries filled) and DAI operation is enabled, interrupt request signaled if not masked
(if LCTM = 1)
3
LCRS: 0 — Left Channel Receive FIFO is less than half full (five or fewer entries filled) or DAI
disabled.
1 — Left Channel Receive FIFO is half full or more (six or more entries filled) and DAI operation is enabled, interrupt request signalled if not masked (if LCRM = 1)
4
Right Channel Transmit FIFO Underrun
0 — Right Channel Transmit FIFO has not experienced an underrun
1 — Right Channel Transmit logic attempted to fetch data from transmit FIFO while it was
empty, request interrupt
5
RCRO: Right Channel Receive FIFO Overrun
0 — Right Channel Receive FIFO has not experienced an overrun
1 — Right Channel Receive logic attempted to place data into receive FIFO while it was full,
request interrupt
6
LCTU: Left Channel Transmit FIFO Underrun
0 — Left Channel Transmit FIFO has not experienced an underrun
1 — Left Channel Transmit logic attempted to fetch data from transmit FIFO while it was empty,
request interrupt
7
LCRO: Left Channel Receive FIFO Overrun
0 — Left Channel Receive FIFO has not experienced an overrun
1 — Left Channel Receive logic attempted to place data into receive FIFO while it was full,
request interrupt
8
RCNF: Right Channel Transmit FIFO Not Full (read-only)
0 — Right Channel Transmit FIFO is full
1 — Right Channel Transmit FIFO is not full
9
RCNE: Right Channel Receive FIFO Not Empty (read-only)
0 — Right Channel Receive FIFO is empty
1 — Right Channel Receive FIFO is not empty
10
LCNF: LCNETelecom Transmit FIFO Not Full (read-only)
0 — Left Channel Transmit FIFO is full
1 — Left Channel Transmit FIFO is not full
Table 62. DAI Control, Data and Status Register Locations (Continued)
112
DS502PP2
CS89712
Bit
Description
11
LCNE: Left Channel Receive FIFO Not Empty (read-only)
0 — Left Channel Receive FIFO is empty
1 — Left Channel Receive FIFO is not empty
12
FIFO: FIFO Operation Completed (read-only)0 — A FIFO Operation has not completed since
the last time this bit was cleared1 — THe FIFO Operation was completed
13
Reserved
14
Reserved
15
Reserved
16-31
Reserved
Table 62. DAI Control, Data and Status Register Locations (Continued)
3.16.6.1 Right Channel Transmit FIFO Service Request Flag (RCTS)
The Right Channel Transmit FIFO Service Request Flag (RCTS) is a read-only bit which is set when
the Right Channel Transmit FIFO is nearly empty and requires service to prevent an underrun. RCTS
is set any time the Right Channel Transmit FIFO has four or fewer entries of valid data (half full or
less), and is cleared when it has five or more entries of valid data. When the RCTS bit is set, an interrupt request is made unless the Right Channel Transmit FIFO interrupt request mask (RCTM) bit
is cleared. After the CPU fills the FIFO such that four or more locations are filled within the Right Channel Transmit FIFO, the RCTS flag (and the service request and / or interrupt) is automatically cleared.
3.16.6.2 Right Channel Receive FIFO Service Request Flag (RCRS)
The Right Channel Receive FIFO Service Request Flag (RCRS) is a read-only bit which is set when
the Right Channel Receive FIFO is nearly filled and requires service to prevent an overrun. RCRS is
set any time the Right Channel Receive FIFO has six or more entries of valid data (half full or more),
and cleared when it has five or fewer (less than half full) entries of data. When the RCRS bit is set,
an interrupt request is made unless the Right Channel Receive FIFO interrupt request mask (RCRM)
bit is cleared. After six or more entries are removed from the receive FIFO, the LCRS flag (and the
service request and / or interrupt) is automatically cleared.
3.16.6.3 Left Channel Transmit FIFO Service Request Flag (LCTS)
The Left Channel Transmit FIFO Service Request Flag (LCTS) is a read-only bit which is set when
the Left Channel Transmit FIFO is nearly empty and requires service to prevent an underrun. LCTS
is set any time the Left Channel Transmit FIFO has four or fewer entries of valid data (half full or less).
It is cleared when it has five or more entries of valid data. When the LCTS bit is set, an interrupt request is made unless the Left Channel Transmit FIFO interrupt request mask (LCTM) bit is cleared.
After the CPU fills the FIFO such that four or more locations are filled within the Left Channel Transmit
FIFO, the LCTS flag (and the service request and / or interrupt) is automatically cleared.
3.16.6.4 Left Channel Receive FIFO Service Request Flag (LCRS)
The Left Channel Receive FIFO Service Request Flag (LCRS) is a read-only bit which is set when
the Left Channel Receive FIFO is nearly filled and requires service to prevent an overrun. LCRS is
set any time the Left Channel Receive FIFO has six or more entries of valid data (half full or more),
and cleared when it has five or fewer (less than half full) entries of data. When the LCRS bit is set, an
interrupt request is made unless the Left Channel Receive FIFO interrupt request mask (LCRM) bit
is cleared. After six or more entries are removed from the receive FIFO, the LCRS flag (and the serDS502PP2
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CS89712
vice request and / or interrupt) is automatically cleared.
3.16.6.5 Right Channel Transmit FIFO Underrun Status (RCTU)
This is set when the Right Channel Transmit logic attempts to fetch data from the FIFO after it has
been emptied. When an underrun occurs, the Right Channel Transmit logic continuously transmits
the last valid right channel value which was transmitted before the underrun. Once data is placed in
the FIFO and it is transferred down to the bottom, the Right Channel Transmit logic uses the new value within the FIFO for transmission. When the RCTU bit is set, an interrupt request is made.
3.16.6.6 Right Channel Receive FIFO Overrun Status (RCRO)
This is set when the right channel receive logic attempts to place data into the Right Channel Receive
FIFO after it has been completely filled. Each time a new piece of data is received, the set signal to
the RCRO status bit is asserted, and the newly received data is discarded. This process is repeated
for each new sample received until at least one empty FIFO entry exists. When this bit is set, an interrupt request is made.
3.16.6.7 Left Channel Transmit FIFO Underrun Status (LCTU)
The Left Channel Transmit FIFO Underrun Status Bit (LCTU) is set when the Left Channel Transmit logic attempts to fetch data from the FIFO after it has been completely emptied. When an underrun occurs, the Left
Channel Transmit logic continuously transmits the last valid left channel value which was transmitted before
the underrun occurred. Once data is placed in the FIFO and it is transferred down to the bottom, the Left Channel
Transmit logic uses the new value within the FIFO for transmission. When the LCTU bit is set, an interrupt request is made.
3.16.6.8 Left Channel Receive FIFO Overrun Status (LCRO)
The Left Channel Receive FIFO Overrun Status Bit (LCRO) is set when the Left Channel Receive logic places data into the Left Channel Receive FIFO after it has been completely filled. Each time a new
piece of data is received, the set signal to the LCRO status bit is asserted, and the newly received
sample is discarded. This process is repeated for each new piece of data received until at least one
empty FIFO entry exists. When the LCRO bit is set, an interrupt request is made.
3.16.6.9 Right Channel Transmit FIFO Not Full Flag (RCNF)
The Right Channel Transmit FIFO Not Full Flag (RCNF) is a read-only bit which is set whenever the
Right Channel Transmit FIFO contains one or more entries which do not contain valid data and is
cleared when the FIFO is completely full. This bit can be polled when using programmed I/O to fill the
Right Channel Transmit FIFO. This bit does not request an interrupt.
3.16.6.10 Right Channel Receive FIFO Not Empty Flag (RCNE)
The Right Channel Receive FIFO Not Empty Flag (RCNELCNF) is a read-only bit which is set when
ever the Right Channel Receive FIFO contains one or more entries of valid data and is cleared when
it no longer contains any valid data. This bit can be polled when using programmed I/O to remove
remaining data from the receive FIFO. This bit does not request an interrupt.
3.16.6.11 Left Channel Transmit FIFO Not Full Flag (LCNF)
This is a read-only bit which is set when ever the Left Channel Transmit FIFO contains one or more
entries which do not contain valid data. It is cleared when the FIFO is full. This bit can be polled when
using programmed I/O to fill the Left Channel Transmit FIFO. This bit does not request an interrupt.
3.16.6.12 Left Channel Receive FIFO Not Empty Flag (LCNE)
This is a read-only bit set when the Left Channel Receive FIFO contains one or more entries of valid
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CS89712
data and is cleared when it no longer contains any valid data. This bit can be polled when using programmed I/O to remove remaining data from the receive FIFO. This bit does not request an interrupt.
3.16.6.13 FIFO Operation Completed Flag (FIFO)
The FIFO Operation Completed (FIFO) Flag is set after the FIFO operation requested by writing to
DAIDR2 as completed.
FIFO is automatically cleared when DAIDR2 is read or written. This bit does not request an interrupt.
3.16.7 DAI64Fs Control (address 0x8000.2600)
The DAI now includes a divider network for the frequency of the clock source. The CS89712 provides
for both 128 and 64 times the sample frequency (128 fs and 64 fs) to better support the various MP3
sample rates. There are two clocks to choose from: 73.728 MHz PLL clock as well as the 11.2896
Mhz external clock. The purpose is support more devices that use the 64 fs rate. Both clocks are fixed
rate clocks so the divider network (AUDIV) is required.
31-15
14-8
7-6
5
AUDDIV
4
LOOPBACK
Bit
3
2
1
0
MCLK256EN
AUDCLKSRC
AUDIOCLKEN
I2SFS64
Description
0
I2SF64: 0 => 128 fs 1=>64 fs If high, SYSCON3 bit 9 must be low. The converse is also true.
1
AUDCLKEN: Enable audio clock generator
2
AUDCLKSRC: Clock Source 0=> 73.728 MHz (PLL) 1=> 11.2896 MHz (Ext Clock)
3
MCLK256EN: Selects MCLK (256 fs) or the BUZZ pin
4
Reserved
5
LOOPBACK: Test mode. Digital data normally output to DAC loops internally.
6-7
Reserved
8-14
AUDIV: Frequency divisor for sample frequency and bit clock using either the external clock or
the PLL clock for the audio clock generator
15-31
Reserved
Table 63. DAI64Fs Control Register
Clock
Source (MHz)
Sample
Frequency (KHz)
128 fs
Audio Bit
Clock (MHz)
64 fs
Audio Bit Clock
(MHz)
128 fs
Divisor
(AUDDIV)
64 fs
Divisor
(AUDDIV)
73.728
8
1.0240
0.5120
36
72
11.2896
11.025
1.4112
0.7056
8
16
73.728
16
1.5360
0.7680
18
36
11.2896
22.050
2.8224
1.4112
4
8
73.728
24
3.0720
1.5360
12
24
73.728
32
4.0960
2.0480
9
18
11.2896
44.1
5.6448
2.8224
2
4
73.728
48
6.1440
3.0720
6
12
Table 64. Clock Source for 64 fs and 128 fs
DS502PP2
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CS89712
3.17 Ethernet Bus Interface Registers
3.17.1 Master Interrupt Enable (address offset 0022h)
Address 0023h
Address 0022h
Interrupt number assignment:
0000 0000b = Enable
0000 01xxb = Disable
00h
Reset value is: XXXX XXXX XXXX X100 - Interrupts disabled
3.17.2 EEPROM Command (address offset 0040h)
7:0
ADD7 to ADD0
F:B
Reserved
A
Reserved
9
OB1
8
OB0
This register is used to control the reading, writing and erasing of the EEPROM. See Section 2.24, “Programming
the EEPROM”.
Bit
Description
7:0
ADD7-ADD0: Address of the EEPROM word being accessed.
9:8
OB1,OB0: Indicates the Opcode of the command being executed. See Table 26.
A
Reserved: Reserved and must be written as 0.
F:B
Reserved: Reserved and must be written as 0.
Table 65. EEPROM Command Bits
Reset value is: XXXX XXXX XXXX XXXX
3.17.3 EEPROM Data (address offset 0042h)
Address 0043h
Most significant byte of the EEPROM data.
Address 0042h
Least significant byte of the EEPROM data.
This register contains the word being written to, or read from, the EEPROM. See Section 2.24, “Programming the
EEPROM”.
Reset value is: XXXX XXXX XXXX XXXX
3.17.4 Receive Frame Byte Counter (address offset 0050h)
Address 0051h
Most significant byte of the byte count.
Address 0050h
Least significant byte of the byte count.
This register contains the count of the total number bytes received in the current received frame. This count continuously increments as more bytes in this frame are received. See Section 2.32, “Basic Receive Operation”.
Reset value is: XXXX XXXX XXXX XXXX
3.18 Ethernet Port Status/Control Registers
3.18.1 Interrupt Status Queue Register (ISQ, address 120h)
7:6
RegContent
5:0
RegNum
F:8
RegContent
The Interrupt Status Queue Register is used to provide interrupt information. Whenever an event occurs that triggers
an enabled interrupt, the Ethernet Port sets the appropriate bit(s) in one of five registers, maps the contents of that
register to the ISQ register, and drives an IRQ pin high. Three of the registers mapped to ISQ are event registers:
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CS89712
RxEvent, TxEvent, and BufEvent. The other two registers are counter-overflow reports: RxMISS and TxCOL. In addition, ISQ is located at offset address 0008h. See Section 2.31, “Managing Interrupts & Status Queue”.
Bit
Description
5:0
RegNum: The lower six bits describe which register (4, 8, C, 10 or 12) is contained in the ISQ.
7:6
F:8
RegContent: The upper ten bits contain the register data contents.
Table 66. Interrupt Status Queue
Reset value is: 0000 0000 0000 0000
3.18.2 Receiver Configuration Register (RxCFG, address offset 102h)
7
RSVD
6
Skip_1
5:0
000011
F
E
ExtradataiE
C
CRCerroriE
B
BufferCRC
A
RSVD
9
RSVD
8
RxOKiE
D
RuntiE
RxCFG determines what frame types will cause interrupts.
Bit
Description
5:0
000011: These bits provide an internal address used by the CS89712 to identify this as register
3, the Receiver Configuration Register.
6
Skip_1: When set, this bit causes the last committed received frame to be deleted from the
receive buffer. To skip another frame, this bit must be set again. This bit is not to be used if
RxDMAonly (Bit 9) is set. Skip_1 is an Act-Once bit. See Section 2.32.4, “Buffering Held
Receive Frames”.
8
RxOKiE: When set, there is an RxOK Interrupt if a frame is received without errors. RxOK
interrupt is not generated when DMA mode is used for frame reception.
A
RSVD: Reserved - must be a “0” when writing to this register.
B
BufferCRC: When set, the received CRC is included with the data stored in the receive-frame
buffer, and the four CRC bytes are included in the receive-frame length (Ethernet Port offset
address 0402h). When clear, neither the receive buffer nor receive length include the CRC.
C
CRCerroriE: When set, there is a CRCerror Interrupt if a frame is received with a bad CRC.
D
RuntiE: When set, ther is a Runt Interrupt if a frame is received that is shorter than 64 bytes.
The CS89712 always discards any frame that is shorter than 8 bytes.
E
ExtradataiE: When set, there is an Extradata Interrupt if a frame is received that is longer than
1518 bytes. The operation of this bit is independent of the received packet integrity (good or
bad CRC).
Table 67. Receiver Configuration
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0000 0011
DS502PP2
117
CS89712
3.18.3 Receiver Event Register, (RxEvent, address offset 124h)
7
Dribblebits
6
IAHash
5:0
000100
F
E
Extradata
C
CRCerror
B
Broadcast
A
Individual Adr
9
Hashed
8
RxOK
D
Runt
Alternate meaning if bits 8 and 9 are both set (see Section 2.32.7, “Receive Ethernet Port Locations” for exception
regarding Broadcast frames).
7
6
5:0
Dribblebits
IAHash
000100
F:A
Hash Table Index (see Section 2.32.7, “Receive
Ethernet Port Locations”)
9
8
Hashed = 1
RxOK = 1
RxEvent reports the status of the current received frame.
Bit
Description
5:0
000100: These bits identify this as register 4, the Receiver Event Register. When reading this
register, these bits will be 000100, where the LSB corresponds to Bit 0.
6
IAHash: If the received frame’s Destination Address is accepted by the hash filter, then this bit
is set if, and only if IAHashA (Register 5, RxCTL, Bit 6) is set, and Hashed (Bit 9) is set. See
Section 2.32.7, “Receive Ethernet Port Locations”.
7
Dribblebits: If set, the received frame had from one to seven bits after the last received full
byte. An "Alignment Error" occurs when Dribblebits and CRCerror (Bit C) are both set.
8
RxOK: If set, the received frame had a good CRC and valid length (i.e., there is not a CRC
error, Runt error, or Extradata error). When RxOK is set, then the length of the received frame
is contained at Ethernet Port offset address 0402h. If RxOKiE (Register 3, RxCFG, Bit 8) is set,
there is an interrupt.
9
Hashed: If set, the received frame had a Destination Address that was accepted by the hash
filter. If Hashed and RxOK (Bit 8) are set, Bits F through A of RxEvent become the Hash Table
Index for this frame [See Section 2.32.7, “Receive Ethernet Port Locations” for an exception
regarding broadcast frames!].If Hashed and RxOK are not both set, then Bits F through A are
individual event bits as defined below.
A
IndividualAdr: If the received frame had a Destination Address which matched the Individual
Address found at Ethernet Port offset address 0158h, then this bit is set if, and only if, RxOK
(Bit 8) is set and IndividualA (Register 5, RxCTL, Bit A) is set.
B
Broadcast: If the received frame had a Broadcast Address (FFFF FFFF FFFFh) as the Destination Address, then this bit is set if, and only if, RxOK is set and BroadcastA (RxCTL register
bit B) is set.
C
CRCerror: If set, the received frame had a bad CRC. If CRCerroriE (Register 3, RxCFG, Bit C)
is set, there is an interrupt.
D
Runt: If set, the received frame was shorter than 64 bytes. If RuntiE (Register 3, RxCFG, Bit D)
is set, there is an interrupt.
E
Extradata: If set, the received frame was longer than 1518 bytes. All bytes beyond 1518 are
discarded. If ExtradataiE (Register 3, RxCFG, Bit E) is set, there is an interrupt.
Table 68. Receiver Event
Reset value is: 0000 0000 0000 0100
Notes: 1. All RxEvent bits are cleared upon readout. The software is responsible for processing all event bits.
2. RxStatus register (Ethernet Port offset address 0400h) is the same as the RxEvent register except
RxStatus is not cleared when RxEvent is read. See Section 2.32, “Basic Receive Operation”. The value
in the RxEvent register is undefined when RxDMAOnly bit (Bit 9, Register 3, RxCFG) is set.
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DS502PP2
CS89712
3.18.4 Receiver Control Register (RxCTL, address offset 104h)
7
PromiscuousA
6
IAHashA
5:0
000101
F
E
ExtradataA
C
CRCerrorA
B
BroadcastA
A
IndividualA
9
MulticastA
8
RxOKA
D
RuntA
RxCTL has two functions: Bits 8, C, D, and E define what types of frames to accept. Bits 6, 7, 9, A, and B configure
the Destination Address filter. See Section 2.32.7, “Receive Ethernet Port Locations”.
Bit
Description
5:0
000101: These bits provide an internal address used by the CS89712 to identify this as register
5, the Receiver Control Register. For a received frame to be accepted, the Destination
Address of that frame must pass the filter criteria found in Bits 6, 7, 9, A, and B (see Section
2.32.7, “Receive Ethernet Port Locations”).
6
IAHashA: When set, receive frames are accepted when the Destination Address is an Individual Address that passes the hash filter.
7
PromiscuousA: Frames with any address are accepted when this bit is set.
8
RxOKA: When set, the CS89712 accepts frames with correct CRC and valid length (valid
length is: 64 bytes <= length <= 1518 bytes).
9
MulticastA: When set, receive frames are accepted if the Destination Address is an Multicast
Address that passes the hash filter.
A
IndividualA: When set, receive frames are accepted if the Destination Address matches the
Individual Address found at Ethernet Port offset address 0158h to 015Dh.
B
BroadcastA: When set, receive frames are accepted if the Destination Address is FFFF FFFF
FFFFh.
C
CRCerrorA: When set, receive frames that pass the Destination Address filter, but have a bad
CRC, are accepted. When clear, frames with bad CRC are discarded. See Note 1.
D
RuntA:When set, receive frames that are smaller than 64 bytes, and that pass the Destination
Address filter are accepted. When clear, received frames less that 64 bytes in length are discarded. The CS89712 discards any frame that is less than 8 bytes. See Note 1.
E
ExtradataA: When set, receive frames longer than 1518 bytes and that pass the Destination
Address filter are accepted. The CS89712 accepts only the first 1518 bytes and ignores the
rest. When clear, frames longer than 1518 bytes are discarded. See Note 1.
Table 69. Receiver Control
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.32.7, “Receive Ethernet Port
Locations”.
Reset value is: 0000 0000 0000 0101
Notes: 1. Typically, when bits CRCerrorA, RuntA and ExtradataA are cleared (meaning bad frames are being
discarded), then the corresponding bits CRCerroriE, RuntiE and ExtradataiE should be set in register 3
(Receiver Configuration register) to allow the device driver to keep track of discarded frames.
DS502PP2
119
CS89712
3.18.5 Transmit Configuration Register (TxCFG, address offset 106h)
7:6
RSVD
5:0
000111
F:C
16colliE
B
AnycolliE
A
JabberiE
9
Out-of-window
8
TxOKiE
Each bit in TxCFG is an interrupt enable. When set, the interrupt is enabled as described below. When clear, there
is no interrupt.
Bit
Description
5:0
000111: These bits provide an internal address used by the CS89712 to identify this as register
7, the Transmit Configuration Register.
8
TxOKiE: When set, an interrupt is generated if a packet is completely transmitted.
9
Out-of-windowiE: When set, an interrupt is generated if a late collision occurs (a late collision
is a collision which occurs after the first 512 bit times). When this occurs, the CS89712 forces a
bad CRC and terminates the transmission.
A
JabberiE: When set, an interrupt is generated if a transmission is longer than approximately 26
ms.
B
AnycolliE: When set, if one or more collisions occur during the transmission of a packet, an
interrupt occurs at the end of the transmission
F:C
16colliE: If the CS89712 encounters 16 normal collisions while attempting to transmit a particular packet, the CS89712 stops attempting to transmit that packet. When this bit is set, there is
an interrupt upon detecting the 16th collision.
7:6
RSVD: Reserved. must be a “0” when writing to this register.
Table 70. Transmit Configuration
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0000 0111
Note:
120
Bit 8 (TxOKiE) and Bit B (AnycolliE) are interrupts for normal transmit operation. Bits 6, 7, 9, A, and Fare
interrupts for abnormal transmit operation.
DS502PP2
CS89712
3.18.6 Transmitter Event Register (TxEvent, address offset 128h)
7:6
RSVD
5:0
001000
F
16coll
E:B
Number-of-Tx-collisions
A
Jabber
9
Out-of-window
8
TxOK
TxEvent gives the event status of the last packet transmitted.
Bit
Description
5:0
001000: These bits provide an internal address used by the CS89712 to identify this as register
8, the Transmitter Event Register.
7:6
RSVD: Reserved. must be a “0” when writing to this register.
8
TxOK: This bit is set if the last packet was completely transmitted (Jabber (Bit A), out-of-window-collision (Bit 9), and 16Coll (Bit F) must all be clear). If TxOKiE (Register 7, TxCFG, Bit 8)
is set, there is an interrupt.
9
Out-of-Window: This bit is set if a collision occurs more than 512 bit times after the first bit of
the preamble. When this occurs, the CS89712 forces a bad CRC and terminates the transmission. If Out-of-windowiE (Register 7, TxCFG, Bit 9) is set, there is an interrupt
A
Jabber: If the last transmission is longer than 26 msec, then the packet output is terminated by
the jabber logic and this bit is set. If JabberiE (Register 7, TxCFG, Bit A) is set, there is an interrupt.
E:B
#-of-TX-collisions: These bits give the number of transmit collisions that occurred on the last
transmitted packet. Bit B is the LSB. If AnycolliE (Register 7, TxCFG, Bit B) is set, there is an
interrupt when any collision occurs.
F
16coll: This bit is set if the CS89712 encounters 16 normal collisions while attempting to transmit a particular packet. When this happens, the CS89712 stops further attempts to send that
packet. If 16colliE (Register 7, TxCFG, Bit F) is set, there is an interrupt.
Table 71. Transmitter Event
Reset value is:
Notes:
DS502PP2
0000 0000 0000 1000
1.In any event register, like TxEvent, all bits are cleared upon readout. The software is responsible for
processing all event bits.
2.TxOK (Bit 8) and the Number-of-Tx-Collisions (Bits E-B) are used in normal packet transmission.All
other bits (6, 7, 9, A, and F) give the status of abnormal transmit operation.
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CS89712
3.18.7 Transmit Command Status register (TxCMD, address offset 108h)
7:6
TxStart
5:0
001001
F
E
D
TxPadDis
C
InhibitCRC
B
A
9
Onecoll
8
Force
This register contains the latest transmit command which describes how the next packet should be sent. The command must be written to Ethernet Port offset 0144h in order to initiate a transmission. The software can read the
command from this register (offset 0108h). See Section 2.34, “Transmit Operation”.
Bit
Description
5:0
001001: These bits provide an internal address used by the CS89712 to identify this as register
9, the Transmit Command Register. When reading this register, these bits will be 001001, where
the LSB corresponds to Bit 0.
7:6
TxStart: This pair of bits determines how many bytes are transferred to the CS89712 before the
MAC starts the packet transmit process.
Bit 7
Bit 6
0
0
Start transmission after 5 bytes are in the CS89712
0
1
Start transmission after 381 bytes are in the CS89712
1
0
Start transmission after 1021 bytes are in the CS89712
1
1
Start transmission after the entire frame is in the CS89712
8
Force: When set in conjunction with a new transmit command, any transmit frames waiting in
the transmit buffer are deleted. If a previous packet has started transmission, that packet is terminated within 64 bit times with a bad CRC.
9
Onecoll: When this bit is set, any transmission will be terminated after only one collision. When
clear, the CS89712 allows up to 16 normal collisions before terminating the transmission.
C
InhibitCRC: When set, the CRC is not appended to the transmission.
D
TxPadDis: When TxPadDis is clear, if the software gives a transmit length less than 60 bytes
and InhibitCRC is set, then the CS89712 pads to 60 bytes. If the software gives a transmit length
less than 60 bytes and InhibitCRC is clear, then the CS89712 pads to 60 bytes and appends the
CRC.
When TxPadDis is set, the CS89712 allows the transmission of runt frames (a frame less than
64 bytes). If InhibitCRC is clear, the CS89712 appends the CRC. If InhibitCRC is set, the
CS89712 does not append the CRC
Table 72. Transmit Command Status
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Regster value is: 0000 0000 0000 1001
Note: The CS89712 does not transmit a frame if TxLength < 3
122
DS502PP2
CS89712
3.18.8 Buffer Configuration Register (BufCFG, address offset 10Ah)
7
RSVD
6
SWint-X
5:0
001011
F
RxDestiE
E
C
TxCol OvfloiE
B
Rx128iE
A
RxMissiE
9
TxUnder runtiE
8
Rdy4TxiE
D
Miss OvfloiE
Each bit in BufCFG enables an interrupt. The corresponding interrupt is enabled when set, and disabled when clear.
Bit
Description
5:0
001011: Identify this as register B, the Buffer Configuration Register.
6
SWint-X: When set, there is an interrupt requested by the software. The Ethernet port provides
the interrupt, and sets the SWint (Register C, BufEvent, Bit 6) bit. The Ethernet port acts upon
this command at once. SWint-X is an Act-Once bit. To generate another interrupt, rewrite a "1"
to this bit.
7
RSVD: Reserved; must be a “0” when writing to this register.
8
Rdy4TxiE: When set, there is an interrupt when the CS89712 is ready to accept a frame from
the software for transmission. (See Section 2.34, “Transmit Operation” for a description of the
transmit bid process.)
9
TxUnderruniE: When set, there is an interrupt if the CS89712 runs out of data before it
reaches the end of the frame (called a transmit underrun). When this happens, event bit
TXUnderrun (Register C, BufEvent, Bit 9) is set and the CS89712 makes no further attempts to
transmit that frame. If the software still wants to transmit that particular frame, the software
must go through the transmit request process again.
A
RxMissiE: When set, there is an interrupt if one or more received frames is lost due to slow
movement of receive data out of the receive buffer (called a receive miss). When this happens,
the RxMiss bit (Register C, BufEvent, Bit A) is set.
B
Rx128iE: When set, there is an interrupt after the first 128 bytes of a frame have been
received. This allows software to examine the Destination Address, Source Address, Length,
Sequence Number, and other information before the entire frame is received. This interrupt
should not be used with DMA. Thus, if either AutoRxDMA (Register 3, RxCFG, Bit A) or RxDMAonly (Register 3, RxCFG, Bit 9) is set, the Rx128iE bit must be clear.
C
TxColOvfiE: If set, there is an interrupt when the TxCOL counter increments from 1FFh to
200h. (The TxCOL counter (Register 18) is incremented whenever the CS89712 sees that the
RXD+/RXD- pins (10BASE-T) go active while a packet is being transmitted.)
D
MissOvfloiE: If MissOvfloiE is set, there is an interrupt when the RxMISS counter increments
from 1FFh to 200h. (A receive miss is said to have occurred if packets are lost due to slow
movement of receive data out of the receive buffers. When this happens, the RxMiss bit (Register C, BufEvent, Bit A) is set, and the RxMISS counter (Register 10) is incremented.)
F
RxDestiE: When set, there is an interrupt when a receive frame passes the Destination
Address filter criteria defined in the RxCTL register (Register 5). This bit provides an early indication of an incoming frame. It is earlier than Rx128 (Register C, BufEvent, Bit B). If RxDestiE
is set, the BufEvent could be RxDest or Rx128. After 128 bytes are received, the BufEvent
changes from RxDest to Rx128.
Table 73. Buffer Configuration
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state after reset. If an
EEPROM is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the
EEPROM”.
Reset value is: 0000 0000 0000 1011
DS502PP2
123
CS89712
3.18.9 Buffer Event Register (BufEvent, address offset 12Ch)
7
RSVD
6
SWint
5:0
001100
F
RxDest
E
C
B
Rx128
A
RxMiss
9
TxUnder run
8
Rdy4Tx
D
BufEvent gives the status of the transmit and receive buffers.
Bit
Description
5:0
001100: These bits provide an internal address used by the CS89712 to identify this as register
C, the Buffer Event Register.
6
SWint: If set, there has been a software initiated interrupt. This bit is used in conjunction with
the SWint-X bit (Register B, BufCFG, Bit 6).
7
RSVD: Reserved; must be a “0” when writing to this register.
8
Rdy4Tx: If set, the CS89712 is ready to accept a frame from the software for transmission. If
Rdy4TxiE (Register B, BufCFG, Bit 8) is set, there is an interrupt. (See Section 2.34, “Transmit
Operation” for a description of the transmit bid process.)
9
TxUnderrun: This bit is set if CS89712 runs out of data before it reaches the end of the frame
(called a transmit underrun). If TxUnderruniE (Register B, BufCFG, Bit 9) is set, there is an
interrupt.
A
RxMiss: If set, one or more receive frames have been lost due to slow movement of data out of
the receive buffers. If RxMissiE (Register B, BufCFG, Bit A) is set, there is an interrupt.
B
Rx128: This bit is set after the first 128 bytes of an incoming frame have been received. This bit
will allow the software the option of preprocessing frame data before the entire frame is
received. If Rx128iE (Register B, BufCFG, Bit B) is set, there is an interrupt.
F
RxDest: When set, this bit shows that a receive frame has passed the Destination Address Filter criteria as defined in the RxCTL register (Register 5). This bit is useful as an early indication
of an incoming frame. It will be earlier than Rx128 (Register C, BufEvent, Bit B). If RxDestiE
(Register B, BufCFG, Bit F) is set, there is an interrupt.
Table 74. Buffer Event
Reset value is: 0000 0000 0000 1100
Notes: With any event register, like BufEvent, all bits are cleared upon readout. The software is responsible for
processing all event bits.
124
DS502PP2
CS89712
3.18.10 Receiver Miss Counter Register (RxMISS, address offset 130h)
7:6
MissCount
5:0
010000
F:8
MissCount
The RxMISS counter (Bits 6 through F) records the number of receive frames that are lost (missed) due to the lack
of available buffer space. If the MissOvfloiE bit (Register B, BufCFG, Bit D) is set, there is an interrupt when RxMISS
increments from 1FFh to 200h. This interrupt provides the software with an early warning that the RxMISS counter
should be read before it reaches 3FFh and starts over (by interrupting at 200h, the software has an additional 512
counts before RxMISS actually overflows). The RxMISS counter is cleared when read.
Bit
Description
5:0
010000: These bits provide an internal address used by the CS89712 to identify this as register
10, the Receiver Miss Counter. When reading this register, these bits will be 010000, where the
LSB corresponds to Bit 0.
7:6
F:8
MissCount: The upper ten bits contain the number of missed frames.
Table 75. Receiver Miss Counter
Register’s value is: 0000 0000 0001 0000
DS502PP2
125
CS89712
3.18.11 Transmit Collision Counter (TxCOL, address offset 132h)
7:6
ColCount
5:0
010010
F:8
ColCount
The TxCOL counter (Bits 6 through F) is incremented whenever the 10BASE-T Receive Pair (RXD+ / RXD-) becomes active while a packet is being transmitted. If the TxColOvfiE bit (Register B, BufCFG, Bit C) is set, there is an
interrupt when TxCOL increments from 1FFh to 200h. This interrupt provides the software with an early warning that
the TxCOL counter should be read before it reaches 3FFh and starts over (by interrupting at 200h, the software has
an additional 512 counts before TxCOL actually overflows). The TxCOL counter is cleared when read.
Bit
Description
5:0
010010: These bits provide an internal address used by the CS89712 to identify this as register
12, the Transmit Collision Counter. When reading this register, these bits will be 010010, where
the LSB corresponds to Bit 0.
7:6
F:8
ColCount: The upper ten bits contain the number of collisions.
Table 76. Transmit Collision Counter
Reset value is: 0000 0000 0001 0010
126
DS502PP2
CS89712
3.18.12 Line Control Register (LineCTL, address offset 112h)
7
SerTxOn
6
SerRxON
5:0
010011
F
E
LoRx Squelch
D
2-part DefDis
C
PolarityDis
B
Mod BackoffE
A
9:8
RSVD
LineCTL determines the configuration of the MAC engine and physical interface.
Bit
Description
5:0
010011: These bits provide an internal address used by the CS89712 to identify this as register
13, the Line Control Register.
6
SerRxON: When set, the receiver is enabled. When clear, no incoming packets pass through
the receiver. If SerRxON is cleared while a packet is being received, reception is completed
and no subsequent receive packets are allowed until SerRxON is set again.
7
SerTxON: When set, the transmitter is enabled. When clear, no transmissions are allowed. If
SerTxON is cleared while a packet is being transmitted, transmission is completed and no subsequent packets are transmitted until SerTxON is set again.
B
ModBackoffE: When clear, the ISO/IEC standard backoff algorithm is used (see Section 2.26,
“Media Access Control Engine”). When set, the Modified Backoff algorithm is used. (The Modified Backoff algorithm extends the backoff delay after each of the first three Tx collisions.)
PolarityDis: The 10BASE-T receiver automatically determines the polarity of the received signal at the RXD+/RXD- input (see Section 2.28, “10BASE-T Transceiver”). When this bit is
clear, the polarity is corrected, if necessary. When set, no effort is made to correct the polarity.
This bit is independent of the PolarityOK bit (Register 14, LineST, Bit C), which reports whether
the polarity is normal or reversed.
2-partDefDis: Before a transmission can begin, the 89712 follows a deferral procedure. With
the 2-partDefDis bit clear, the CS89712 uses the standard two-part deferral as defined in
ISO/IEC 8802-3 paragraph 4.2.3.2.1. With the 2-partDefDis bit set, the two-part deferral is disabled.
LoRxSquelch: When clear, the 10BASE-T receiver squelch thresholds are set to levels
defined by the ISO/IEC 8802-3 specification. When set, the thresholds are reduced by approximately 6 dB. This is useful for operating with "quiet" cables that are longer than 100 meters.
RSVD: Reserved; must be a “0” when writing to this register.
C
D
E
9:8
Table 77. Line Control
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0001 0011
DS502PP2
127
CS89712
3.18.13 Line Status Register (LineST, address offset 134h)
7
LinkOK
6
5:0
010100
F
E
CRS
C
PolarityOK
B
A
9
10BT
8
RSVD
LineST reports the status of the Ethernet physical interface.
Bit
Description
5:0
010100: These bits provide an internal address used by the CS89712 to identify this as register
14, the Line Status Register. When reading this register, these bits will be 010100, where the
LSB corresponds to Bit 0.
7
LinkOK: If set, the 10BASE-T link has not failed. When clear, the link has failed, either
because the CS89712 has just come out of reset, or because the receiver has not detected
any activity (link pulses or received packets) for at least 50 ms.
8
RSVD: Reserved; must be a “0” when writing to this register.
9
10BT: If set, the CS89712 is using the 10BASE-T interface.
C
PolarityOK: If set, the polarity of the 10BASE-T receive signal (at the RXD+ / RXD- inputs) is
correct. If clear, the polarity is reversed. If PolarityDis (Register 13, LineCTL, Bit C) is clear, the
polarity is automatically corrected, if needed. The PolarityOK status bit shows the true state of
the incoming polarity independent of the PolarityDis control bit. Thus, if PolarityDis is clear and
PolarityOK is clear, then the receive polarity is inverted, and corrected.
E
CRS: This bit tells the software the status of an incoming frame. If CRS is set, a frame is currently being received. CRS remains asserted until the end of frame (EOF). At EOF, CRS goes
inactive in about 1.3 to 2.3 bit times after the last low-to-high transition of the recovered data.
Table 78. Line Status
Reset value is: 0000 0000 0001 0100
128
DS502PP2
CS89712
3.18.14 Self Control Register (SelfCTL, address offset 114h)
7
6
RESET
5:0
010101
F
HCB1
E
HCB0
C
HC0E
B
A
RESERVED
9
RESERVED
8
SW Suspend
D
RESERVED
SelfCTL controls the operation of the LED outputs and the lower-power modes.
Bit
Description
5:0
010101: These bits provide an internal address used by the CS89712 to identify this as register
15, the Self Control Register.
6
RESET: When set, a chip-wide reset is initiated immediately. RESET is an Act-Once bit. This
bit is cleared as a result of the reset.
8
SWSuspend: When set, the CS89712 Ethernet port enters the software initiated Suspend
mode. Upon entering this mode, there is a partial reset. All Ethernet registers and circuits are
reset. There is no transmit nor receive activity in this mode. To come out of software Suspend,
the software issues an Write within the Ethernet port’s assigned memory space.
C
HC0E: The LINKLED or HC0 output pin is selected with this control bit. When HC0E is clear,
the output pin is LINKLED. When HC0E is set, the output pin is HC0 and the HCB0 bit (Bit E)
controls the pin.
E
HCB0: When HC0E (Bit C) is set, this bit controls the HC0 pin. If HCB0 is set, HC0 is low. If
HCB0 is clear, HC0 is high. HC0 may drive an LED or a logic gate. When HC0E (Bit C) is clear,
this control bit is ignored.
F
HCB1: When HC1E (Bit D) is set, this bit controls the HC1 pin. If HCB1 is set, HC1 is low. If
HCB1 is clear, HC1 is high. HC1 may drive an LED or a logic gate. When HC1E (Bit D) is clear,
this control bit is ignored.
Table 79. Self Control
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0001 0101
DS502PP2
129
CS89712
3.18.15 Self Status Register (SelfST, address offset 136h)
7
INITD
6
3.3V Active
5:0
010110
F
E
C
EEsize
B
RSVD
A
EEPROM OK
9
EEPROM present
8
SIBUSY
D
SelfST reports the status of the EEPROM interface and the initialization process.
Bit
Description
5:0
010110: These bits provide an internal address used by the CS89712 to identify this as register
16, the Self Status Register. When reading this register, these bits will be 010110, where the
LSB corresponds to Bit 0.
6
3,3VActive: If the CS89712 is operating on a 3.3 V supply, this bit is set. If the CS89712 is
operating on a 5V supply, this bit is clear.
7
INITD: If set, the CS89712 initialization, including read-in of the EEPROM, is complete.
8
SIBUSY: If set, the EECS output pin is high indicating that the EEPROM is currently being read
or programmed. The software must not write to Ethernet Port offset address 0040h nor 0042h
until SIBUSY is clear.
9
EEPROMpresent: If the EEDataIn pin is low after reset, there is no EEPROM present, and the
EEPROMpresent bit is clear. If the EEDataIn pin is high after reset, the CS89712 "assumes"
that an EEPROM is present, and this bit is set.
A
EEPROMOK: If set, the checksum of the EEPROM readout was OK.
B
RSVD: Reserved; must be a “0” when writing to this register.
C
EEsize: This bit shows the size of the attached EEPROM and is valid only if the EEPROMpresent bit (Bit 9) and EEPROMOK bit (Bit A) are both set. If clear, the EEPROM size is either 128
words ('C56 or 'CS56) or 256 words (C66 or 'CS66). If set, the EEPROM size is 64 words ('C46
or 'CS46).
Table 80. Self Status
Reset value is: 0000 0000 0001 0110
130
DS502PP2
CS89712
3.18.16 Ethernet IRQ Control Register (BusCTL, address offset 116h)
7
6
RSVD
Bit
5:0
010111
F
EnableIRQ
E
D:8
RSVD
Description
5:0
010111: These bits provide an internal address used by the CS89712 to identify this as register
17, the Bus Control Register.
6
D:8
RSVD: Reserved; must be a “0” when writing to this register.
F
EnableIRQ: When set, the CS89712 will generate an interrupt in response to an interrupt event
(Section 2.31, “Managing Interrupts & Status Queue”). When cleared, the CS89712 will not
generate any interrupts.
Table 81. Ethernet IRQ Control
After reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM
is found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0001 0111
DS502PP2
131
CS89712
3.18.17 TX Bid Status Register (BusST, address offset 138h)
7
TxBidErr
6
5:0
011000
F
E
C
B
A
9
8
Rdy4Tx NOW
D
BusST describes the status of the current transmit operation.
Bit
Description
5:0
011000: These bits provide an internal address used by the CS89712 to identify this as register
18, the Bus Status Register. When reading this register, these bits will be 011000, where the
LSB corresponds to Bit 0.
7
TxBidErr: If set, the software has commanded the Ethernet port to transmit a frame that the
Ethernet port will not send. Frames that the Ethernet port will not send are:
1) Any frame greater than 1514 bytes, provided that InhibitCRC
(Register 9, TxCMD, Bit C) is clear.
2) Any frame greater than 1518 bytes.
Note that this bit is not set when transmit frames are too short.
8
Rdy4TxNOW: Rdy4TxNOW signals the software that the Ethernet port is ready to accept a
frame from the software for transmission. This bit is similar to Rdy4Tx (Register C, BufEvent,
Bit 8) except that there is no interrupt associated with Rdy4TxNOW. The software can poll the
CS89712 and check Rdy4TxNOW to determine if the CS89712 is ready for transmit. (See Section 2.34, “Transmit Operation” for a description of the transmit bid process.)
Table 82. TX Bid Status
Reset value is: 0000 0000 0001 1000
132
DS502PP2
CS89712
3.18.18 Test Control Register (TestCTL, address offset 0118h)
7
DisableLT
6
5:0
011001
F
E
FDX
C
B
Disable Backoff
A
RSVD
9
ENDEC loop
8
D
TestCTL controls the diagnostic test modes of the CS89712.
Bit
Description
011001: These bits provide an internal address used by the CS89712 to identify this as register
19, the Test Control Register.
DisableLT: When set, the 10BASE-T interface allows packet transmission and reception
regardless of the link status. DisableLT is used in conjunction with the LinkOK (Register 14,
LineST, Bit 7) as follows:
LinkOK
DisableLT
0
0
No packet transmission for reception allowed.
Transmitter sends link impulses.
0
1
DisableLT overrides LinkOK to allow packet
transmission and reception. Transmitter does not
send link pulses.
1
N/A
Disable has no meaning if LinkOK = 1.
ENDECloop: When set, the CS89712 enters internal loopback mode where the internal
Manchester encoder output is connected to the decoder input. The 10BASE-T are disabled.
When clear, the CS89712 is configured for normal operation
Disable Backoff: When set, the backoff algorithm is disabled. The CS89712 transmitter looks
only for completion of the inter packet gap before starting transmission. When clear, the backoff algorithm is used.
FDX: When set, 10BASE-T full duplex mode is enabled and CRS (Register 14, LineST, Bit E)
is ignored. This bit must be set when performing loopback tests on the 10BASE-T port. When
clear, the CS89712 is configured for standard half-duplex 10BASE-T operation.
RSVD: Reserved; must be a “0” when writing to this register.
Table 83. Test Control
At reset, if no EEPROM is found by the CS89712, then the register has the following initial state. If an EEPROM is
found, then the register’s initial value may be set by the EEPROM. See Section 2.24, “Programming the EEPROM”.
Reset value is: 0000 0000 0001 1001
3.19 Initiate Transmit Registers
3.19.1 Transmit Command Request Register (TxCMD, address offset 144h)
7:6
TxStart
5:0
001001
F
E
D
TxPadDis
C
InhibitCRC
B
A
9
Onecoll
8
Force
The word written to offset 0144h tells the CS89712 how the next packet should be transmitted. Note that this Ethernet Port location is write-only, and the written word can be read from Ethernet address offset 0108h. The
DS502PP2
133
CS89712
CS89712 does not transmit a frame if TxLength is less than 3. See Section 2.34, “Transmit Operation”.
Bit
Description
001001: These bits provide an internal address used to identify this as register 9. When reading this register, these bits will be 001001, where the LSB corresponds to Bit 0.
TxStart: This pair of bits determines how many bytes are transferred to the CS89712 before
the MAC starts the packet transmit process.
Bit 7
Bit 6
0
0
Start transmission after 5 bytes are in the CS89712
0
1
Start transmission after 381 bytes are in the CS89712
1
0
Start transmission after 1021 bytes are in the CS89712
1
1
Start transmission after the entire frame is in the CS89712
Force: When set in conjunction with a new transmit command, any transmit frames waiting in
the transmit buffer are deleted. If a previous packet has started transmission, that packet is terminated within 64 bit times with a bad CRC.
Onecoll: When this bit is set, any transmission will be terminated after only one collision. When
clear, the CS89712 allows up to 16 normal collisions before terminating the transmission.
InhibitCRC: When set, the CRC is not appended to the transmission.
TxPadDis: When TxPadDis is clear, if the software gives a transmit length less than 60 bytes
and InhibitCRC is set, then the Ethernet port pads to 60 bytes. If the software gives a transmit
length less than 60 bytes and InhibitCRC is clear, then the CS89712 pads to 60 bytes and
appends the CRC.
When TxPadDis is set, the CS89712 allows the transmission of runt frames (a frame less than
64 bytes). If InhibitCRC is clear, the CS89712 appends the CRC. If InhibitCRC is set, the
CS89712 does not append the CRC.
Table 84. Transmit Command
Since this register is write-only, its initial state after reset is undefined.
3.19.2 Transmit Length (TxLength, address offset 146h)
Address 0147h
Most-significant byte of Transmit Frame Length
Address 0146h
Least-significant byte of Transmit Frame Length
This register is used in conjunction with the TxCMD register. When a transmission is initiated via a command in TxCMD, the length of the transmitted frame is written into this register. The length of the transmitted frame may be
modified by the configuration of the TxPadDis and InhibitCRC bits in the TxCMD register. See Table 30, and Section
2.34, “Transmit Operation”. TxLength must be >3 and < 1519.
Since this register is write-only, its initial state after reset is undefined.
3.20 Address Filter Registers
3.20.1 Logical Address Filter (hash table, address offset 0150h)
Address 0157h Address 0156h Address 0155h Address 0154h Address 0153h Address 0152h Address 0151h Address 0150h
Most-signifiLeast-significant byte of
cant byte of
hash filter.
hash filter.
The CS89712 hashing decoder circuitry compares its output with one bit of the Logical Address Filter Register. If
the decoder output and the Logical Address Filter bit match, the frame passes the hash filter and the Hashed bit
134
DS502PP2
CS89712
(Register 4, RxEvent, Bit 9) is set. See Section 2.32.7, “Receive Ethernet Port Locations”.
Reset value is: 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
3.20.2 Individual Address (IEEE or MAC address, address offset 0158h)
Address 0015Dh
Octet 5 of IA
Address 015Ch
Address 015Bh
Address 015Ah
Address 0159h
Address 0158h
Octet 0 of IA
For example: if the MAC address is “00242010ABCD” then load register address 0158h with 00h, 0159h with 24h,
015Ah with 21h, etc.
The value of this register must be loaded from external storage, for example, from the EEPROM. See Section 2.24,
“Programming the EEPROM”. If the CS89712 is not able to load the IA from the EEPROM, then after a reset this
register is undefined, and the driver must write an address to this register.
DS502PP2
135
CS89712
4. TEST & DEBUG MODES
4.1.2
The CS89712 supports a number of hardware activated test and debug modes.
This mode is selected by nTEST[0] = 0,
nTEST[1] = 1, Latched nURESET = 0
4.1 Entering test modes
This test mode will enable the main oscillator and
will output various buffered clock and test signals
derived from the main oscillator, PLL, and 32-kHz
oscillator. All internal logic in the CS89712 will be
static and isolated from the oscillators, with the exception of the 6-bit ripple counter used to generate
576 kHz and the Real-Time Clock divide chain.
Port A is used to drive the inputs of the PLL directly, and the various clock and PLL outputs are monitored on the COL pins. Table 86 defines the
CS89712 signal pins used in this test mode. This
mode is only intended to allow test of the oscillators and PLL. Note that these inputs are inverted
before being passed to the PLL to ensure that the
default state of the port (all zero) maps onto the correct default state of the PLL (TSEL = 1, XTALON
= 1, PLLON = 1, D0 = 0, D1 = 1, PLLBP = 0). This
state will produce the correct frequencies as shown
in Table 86. Any other combinations are for testing
the oscillator and PLL and should not be used incircuit.
Test modes are activated by the pin combinations
shown in Table 85. All latched signals will only alter test modes while NPOR is low, their state is
latched on the rising edge of NPOR. This allows
these signals to be used normally during various
test modes.
Within each test mode, a selection of pins is used as
multiplexed outputs or inputs to provide / monitor
the test signals unique to that mode.
4.1.1
Oscillator and PLL Bypass Mode
This mode is selected by nTEST[0] = 1 and
nTEST[1] = 0.
In this mode, all the internal oscillators and PLL are
disabled, and the appropriate crystal oscillator pins
become the direct external oscillator inputs bypassing the oscillator and PLL. MOSCIN must be driven by a 36.864 MHz clock source and RTCIN by a
32.768 kHz source.
Test Mode
Oscillator and PLL Test Mode
Latched
nMEDCHG
Latched
PE[0]
Latched
PE[1]
Latched
nURESET
nTEST[0]
nTEST[1]
Normal operation
(32-bit boot)
1
0
0
X
1
1
Normal operation
(8-bit boot)
1
1
0
X
1
1
Normal operation
(16-bit boot)
1
0
1
X
1
1
Alternative test ROM
boot
0
X
X
X
1
1
Oscillator / PLL bypass
X
X
X
X
1
0
Oscillator / PLL test
mode
X
X
X
0
0
1
ICE Mode
X
X
X
1
0
0
System test (all HiZ)
X
X
X
0
0
0
Table 85. CS89712 Hardware Test Modes
136
DS502PP2
CS89712
Signal
I/O
Pin
Function
TSEL *
I
PA5
PLL test mode
XTLON *
I
PA4
Enable to oscillator circuit
PLLON *
I
PA3
Enable to PLL circuit
PLLBP
I
PA0
Bypasses PLL
RTCCLK
O
COL0
Output of RTC oscillator
CLK1
O
COL1
1 Hz clock from RTC divider chain
OSC36
O
COL2
36 MHz divided PLL main clock
CLK576K
O
COL4
576 KHz divided from above
VREF
O
COL6
Test clock output for PLL
Table 86. Oscillator and PLL Test Mode Signals
4.1.3
Debug / ICE Test Mode
This mode is selected by nTEST0 = 0, nTEST1 =
0, Latched nURESET = 1.
Selection of this mode enables the debug mode of
the ARM720T. By default, this is disabled which
saves approximately 3% on power.
4.1.4
Hi-Z (System) Test Mode
cesses and for any accesses to the standard address
range for nCS[5]. Additionally, in this mode, the
internal signals shown in Table 87 are multiplexed
out of the device on port pins.
Signal
I/O
Pin
Function
CLK
O
PE0
Waited clock to CPU
nFIQ
O
PE1
nFIQ interrupt to CPU
nIRQ
O
PE2
nIRQ interrupt to CPU
This mode selected by nTEST0 = 0, nTEST1 = 0,
Latched nURESET = 0.
Table 87. Software Selectable Test Functionality
This test mode asynchronously disables all output
buffers on the CS89712. This has the effect of removing the CS89712 from the PCB so that other
devices on the PCB can be in-circuit tested. The internal state of the CS89712 is not altered directly
by this test mode.
This test is not intended to be used when LCD
DMA accesses are enabled. This is due to the fact
that it is possible to have internal peripheral bus activity simultaneously with a DMA transfer. This
would cause bus contention to occur on the external
bus.
4.1.5
The “Waited clock to CPU” is an internally ANDed
source that generates the actual CPU clock. Thus, it
is possible to know exactly when the CPU is being
clocked by viewing this pin. The signals nFIQ and
nIRQ are the two output signals from the internal
interrupt controller. They are input directly into the
ARM720T processor.
Software Selectable Test Functionality
When bit 11 of the SYSCON register is set high, internal peripheral bus register accesses are output on
the main address and data buses as though they
were external accesses to the address space addressed by nCS[5]. Hence, nCS[5] takes on a dual
role, it will be active as the strobe for internal ac-
DS502PP2
137
CS89712
4.1.6
Loopback/Collision Diagnostic Tests
4.1.8
Internal and external Loopback and Collision tests
can be used to verify the CS89712’s Ethernet port
functionality. Internal tests allow the major digital
functions to be tested, independent of the analog
functions. During these tests, the Manchester encoder is connected to the decoder. All digital circuits are operational, and the transmitter and
receiver are disabled. External test modes allow the
complete chip to be tested without connecting it directly to an Ethernet network.
4.1.7
10BASE-T Loopback/Collision Tests
10BASE-T Loopback and Collision Tests are controlled by two bits in the Test Control register:
FDX (Register 19, TestCTL, Bit E) and ENDECloop (Register 19, TestCTL, Bit 9). Table 88 describes these tests.
4.2 In-Circuit Emulation
4.2.1
Introduction
EmbeddedICE™ is an extension to the architecture
of the ARM family of processors, and provides the
ability to debug cores that are deeply embedded
into systems. It consists of three parts:
Loopback Tests
During Loopback tests, the internal Carrier Sense
(CRS) signal, used to detect collisions, is ignored,
allowing packet reception during transmission.
1) A set of extensions to the ARM core
2) The EmbeddedICE macrocell, which provides
external access to the extensions
Test Mode
FDX
ENDECloop
DisableLT
Description of Test
10BASE-T Internal
Loopback
1
1
1
Transmit a frame and verify that the frame is
received without error.
10BASE-T Internal
Collision
0
1
1
Transmit frames and verify that collisions are
detected and that the internal counters function
properly. After 16 collisions, verify that 16coll
(Register 8, TxEvent, Bit F) is set.
10BASE-T
External Loopback
1
0
0
Connect TXD+ to RXD+ and TXD- to RXD-.
Transmit a frame and verify that the frame is
received without error.
10BASE-T
External Collision
0
0
0
Connect TXD+ to RXD+ and TXD- to RXD-.
Transmit frames and verify that collisions are
detected and that internal counters function
properly. After 16 collisions, verify that 16coll
(Register 8, TxEvent, Bit F) is set.
Table 88. 10BASE-T Loopback and Collision Tests
138
DS502PP2
CS89712
3) The EmbeddedICE interface, which provides
communication between the host computer and
the EmbeddedICE macrocell
The EmbeddedICE macrocell is programmed, in a
serial fashion, through the TAP controller on the
ARM via the JTAG interface. The EmbeddedICE
macrocell is by default disabled to minimize power
usage, and must be enabled at boot-up to support
this functionality.
4.2.2
Functionality
The ICEBreaker module consists of two real-time
watchpoint units together with a control and status
register. One or both of the units can be programmed to halt the execution of the instructions
by the ARM processor. Execution is halted when
either a match occurs between the values programmed into the ICEBreaker and the values currently appearing on the address bus, data bus, and
DS502PP2
the various control signals. Any bit can be masked
to remove it from the comparison. Either unit can
be programmed as a watchpoint (monitoring data
accesses) or a breakpoint (monitoring instruction
fetches).
Using one of these watchpoint units, an unlimited
number of software breakpoints (in RAM) can be
supported by substitution of the actual code.
Note:
The EXTERN[1:0] signals from the ICEBreaker
module are not wired out in this device. This
mechanism is used to allow watchpoints to be
dependent on an external event. This behavior
can be emulated in software via the ICEBreaker
control registers.
A more detailed description is available in the
ARM Software Development Toolkit User Guide
and Reference Manual. The ICEBreaker module
and its registers are fully described in the
“ARM7TDMI” Data Sheet.
139
CS89712
5. MECHANICAL INFORMATION
5.1 256-PBGA PIN DIAGRAM
16
15
14
13
TXDN
N/C
N/C
VssA
Vss
I/O
VssA
10
9
8
7
6
5
4
3
2
1
RXDP RXDN
12
11
RES
VssA
XTAL
1
XTAL
2
EECS
EE
DOUT
Vss
I/O
DD
3
SD
CS0
CS
0
A
VddA
VddA
LINK
LED
LAN
LED
VssA
EESK
EE
DIN
N/C
DD
2
SDQM
CS
1
B
N/C
Vss
I/O
N/C
Vdd
I/O
CL
1
DD
1
SDQM
CS
3
C
2
TXDP
VddA
VssA
D
3
D
4
D
5
Vss
I/O
D
6
Vdd
I/O
N/C
MOE/
Vdd
I/O
Vss
I/O
D
2
N/C
A
19
D
0
N/C
D
15
D
13
N/C
Vdd
CORE
FRM
DD
0
SD
CKE
CS
4
D
SDCAS
A
16
A
15
D
1
A
18
A
6
A
17
MWE/
SDWE
D
12
Vss
I/O
D
10
Vdd
I/O
CL
2
M
SD
CS1
SD
CLK
EXP
CLK
E
A
14
A
13
Vss
I/O
Vss
I/O
A
4
A
5
WAKE
UP
PWR
FL
Vdd
I/O
D
11
Vss
CORE
Vss
I/O
Vdd
I/O
Vss
I/O
CS
5
WORD
F
A
12
VDD
I/O
A
11
A
3
ETH
ENBL
Vss
I/O
Vdd
OSC
MOSC
Vss
OSC
Vss
I/O
Vss
I/O
TXD
2
TDI
EXP
RDY
Vdd
I/O
WRITE
G
A
10
A
9
A
7
ETH
ENBL
uRST
Vss
I/O
Vss
I/O
MOSC
PA
4
PA
6
PB
6
PB
5
PB
1
RXD
2
Vss
I/O
RUN
H
OUT
N/C
A
2
A
1
D
7
nMED
CHG
D
8
Vss
I/O
TEST
1
PE
2
LED
DRV
Vdd
I/O
PA
3
TDO
PB
4
PB0/
PB
7
J
PRDY1
N/C
A
0
N/C
nBAT
CHG
A
8
Vdd
I/O
SSI
TXDA
SSI
TXFR
PD
1
PD
2
TEST
0
PA
1
PHD
IN
PA
5
PB
2
PB
3
K
Vdd
I/O
Vdd
I/O
BAT
OK
VSS
I/O
D
9
D
14
Vss
I/O
DRV
0
SSI
RXFR
DRV
1
PD
3
PE
0
TXD
1
CTS
PA
2
PA
7
L
Vss
I/O
nEXT
PWR
D
17
COL
6
Vdd
I/O
FB
0
ADC
CLK
Vss
I/O
Vdd
I/O
PE
1
RXD
1
Vss
I/O
DSR
PA
0
M
PD
5
nEXT
FIQ
N/C
nEINT
1
DCD
N
SSI
PD6/
RXDA SDQM0
Vdd
RTC
Vss
RTC
nEINT
2
P
RTC
IN
R
PD7/
T
nPOR nTRST
IN
N/C
3
D
18
D
21
D
16
D
19
Vdd
I/O
COL
1
COL
0
COL
2
COL
7
SMP
CLK
ADC
CS
A
20
A
23
D
20
D
22
A
22
D
28
Vss
I/O
D
31
COL
3
FB
1
Vdd
I/O
D
23
D
24
A
21
Vss
I/O
Vdd
I/O
Vss
I/O
A
27
D
30
BUZ
COL
4
Vdd
I/O
ADC
IN
PD
0
PD
4
RTC
OUT
HALF
D
25
A
25
D
26
A
26
D
27
D
29
TCLK
COL
5
ADC
OUT
Vdd
I/O
Vss
I/O
SSI
CLK
TMS
A24
WORD
SDQM1
Table 89. 256-Ball PBGA Ball Listing (bottom view)
140
DS502PP2
CS89712
5.2 External Signal Functions
Function
Signal
Name
Signal
Data bus
D[0-31]
I/O
32-bit system data bus for memory, DRAM, and I/O interface
A[0-14]
O
15 bits of system byte address during memory and expansion cycles
Address bus
A[13-27]
DRA[0-14]
DRA[0-14] is multiplexed with A[13-27], offering additional power savings since the lightest loading is expected on the high order ROM
address lines.
Whenever the CS89712 is in the Standby State, the external address
and data buses are driven low. The RUN signal is used internally to
force these buses to be driven low. This is done to prevent peripherals that are powered-down from draining current. Also, the internal
peripheral’s signals get set to their Reset State.
BA[0-1]/A[13/14]
SDCS[0-1]
Memory
Interface
Description
I/O
SDRAM bank select pins.
A2, E3
O
SDRAM chip selects.
SDCLK
E2
O
SDRAM clock.
SDCKE
D2
O
SDRAM clock enable.
SDQM[2-3]
C2, B2
nMOE/nSDCAS
D16
O
Memory output enable/SDRAM CAS control signal
SDRAM byte masks. SDQM0-1 are muxed with Port D data pins.
nMWE/nSDWE
E10
O
Memory write enable/SDRAM write enable control signal
nCS[0-1, 3]
A1, B1,
C1
O
Chip select; active low, SRAM-like chip selects for expansion
Ethernet Enable
/ nCS2
G12,
H13
O
Chip select; active low, indicates either Ethernet port or CS2 expansion range activity. Pins G12 and H13 must be tied together.
nCS[4-5]
D1, F2
O
Chip select; active low, CS for expansion or for CL-PS6700 select
EXPRDY
G3
I
Expansion port ready; external expansion devices drive this low to
extend the bus cycle. This is used to insert wait states for an external
bus cycle.
WRITE
G1
O
Write strobe, low during reads, high during writes from the CS89712
WORD/
HALFWORD
F1
T15
O
To do write accesses of different sizes Word and Half-Word must be
externally decoded. The encoding of these signals is as follows:
Access Size
Word
Half-Word
Byte
Word
1
*
0
Half-Word
0
1
0
EXPCLK
E1
I/O
nMEDCHG/
nBROM
J12
I
Media changed input; active low, deglitched. Used as a general purpose FIQ interrupt during normal operation. It is also used on power
up to configure the processor to either boot from the internal Boot
ROM, or from external memory. When low, the chip will boot from the
internal Boot ROM.
nEXTFIQ
N4
I
External active low fast interrupt request input
nEINT[1:2]
N2, P1
I
Two general purpose, active low interrupt inputs
Interrupts
Expansion clock rate is the same as the CPU clock for 18 MHz. It
runs at 36.864 MHz for 36,49 and 74 MHz modes.
Table 90. External Signal Functions
DS502PP2
141
CS89712
Function
Power
Management
Signal
Name
Signal
Description
nPWRFL
F9
I
Power fail input; active low, deglitched input to force system into the
Standby State (Note 1)
BATOK
L14
I
Main battery OK input; falling edge generates a FIQ, a low level in the
Standby State inhibits system start up; deglitched input (Note 2)
nEXTPWR
M13
I
External power sense; must be driven low if the system is powered by
an external source
nBATCHG
K13
I
New battery sense; driven low if battery voltage falls below the "nobattery" threshold; it is a deglitched input (Note 2)
nPOR
M16
I
Power-on reset input. This signal is not deglitched. When active it
completely resets the entire system, including all the RTC registers.
Upon power-up, the signal must be held active low for a minimum of
100 µsec after VDD has settled. During normal operation, nPOR
needs to be held low for at least one clock cycle of the selected clock
speed (i.e., when running at 74 MHz, the pulse width of nPOR needs
to be > 14 nsec).
State Control
Note that nURESET, TEST(0), TEST(1), PE(0), PE(1), PE(2),
DRIVE(0), DRIVE(1), DD(0), DD(1), DD(2), and DD(3) are all latched
on the rising edge of nPOR.
DAI, Codec or
SSI2
Interface
(See Table 22 )
.
ADC
Interface
(SSI1)
RUN
H1
O
This pin is the RUN signal. The pin will be high when the system is
active or idle, low while in the Standby State. See Table 91.
WAKEUP
F10
I
Wake up is a deglitched input signal. It must be held high for at least
125 µsec to guarantee its detection. Once detected it forces the system into the Operating State from the Standby State. It is only active
when the system is in the Standby State. This pin is ignored when the
system is in the Idle or Operating State. It is used to wakeup the system after first power-up, or after software has forced the system into
the Standby State. WAKEUP will be ignored for up to two seconds
after nPOR goes HIGH. Therefore, the external WAKEUP logic must
be designed to allow it to rise and stay HIGH for at least 125 usec,
two seconds after nPOR goes HIGH. (Note 2)
nURESET
H12
I
User reset input; active low deglitched input from user reset button.
This pin is also latched upon the rising edge of nPOR and read along
with the input pins nTEST[0-1] to force the device into special test
modes. nURESET does not reset the RTC. (Note 2)
SSICLK
T3
I/O
DAI/Codec/SSI2 clock signal
SSITXFR
K9
I/O
DAI/Codec/SSI2 serial data output frame/synchronization pulse output
SSITXDA
K10
O
DAI/Codec/SSI2 serial data output
SSIRXDA
P5
I
DAI/Codec/SSI2 serial data input
SSIRXFR
L8
I/O
SSI2 serial data input frame/synchronization pulse
DAI external clock input
ADCCLK
M8
O
Serial clock output
nADCCS
N6
O
Chip select for ADC interface
ADCOUT
T6
O
Serial data output
ADCIN
R5
I
Serial data input
SMPCLK
N7
O
Sample clock output
Table 90. External Signal Functions (Continued)
142
DS502PP2
CS89712
Function
IrDA and
RS232
Interfaces
LCD
Signal
Name
Signal
LEDDRV
J7
O
Infrared LED drive output (UART1)
PHDIN
K4
I
Photo diode input (UART1)
TXD[1-2]
L4, G5
O
RS232 UART1 and 2 TX outputs
RXD[1-2]
M4, H3
I
RS232 UART1 and 2 RX inputs
DSR
M2
I
RS232 DSR input
DCD
N1
I
RS232 DCD input
RS232 CTS input
CTS
L3
I
DD[0-3]
D3, C3,
B3, A3
I/O
LCD serial display data; pins can be used on power up to read
the ID of some LCD modules (See Figure 31).
CL[1]
C4
O
LCD line clock
CL[2]
E5
O
LCD pixel clock
FRM
D4
O
LCD frame synchronization pulse output
M
E4
O
LCD AC bias drive
O
Keyboard column drives (SYSCON1)
BUZ
R8
O
Buzzer drive output (SYSCON1)
PD[0]/
LEDFLSH
R4
O
LED flasher driver — multiplexed with Port D bit 0. This pin can provide up to 4 mA of drive current.
PA[0:7]
I/O
Port A I/O (bit 6 for boot clock option, bit 7 for CL-PS6700 PRDY
input); also used as keyboard row inputs
PB[0]/PRDY1
PB[1]/PRDY2
PB[2:7]
I/O
Port B I/O. All eight Port B bits can be used as GPIOs.
When the PC CARD1 or 2 control bits in the SYSCON2 register are
de-asserted, PB[0] and PB[1] are available for GPIO. When
asserted, these port bits are used as the PRDY signals for connected
CL-PS6700 PC Card Host Adapter devices.
COL[0-7]
Keyboard and
Buzzer drive
LED Flasher
General
Purpose I/O
PD[0:7]
I/O
Port D I/O
PE[0]/
BOOTSEL[0]
L5
I/O
Port E I/O (3 bits only). Can be used as general purpose I/O during
normal operation.
PE[1]/
BOOTSEL[1]
M5
I/O
During power-on reset, PE[0] and PE[1] are inputs and are latched by
the rising edge of nPOR to select the memory width that the CS89712
will use to read from the boot code storage device (i.e., external 8-bitwide FLASH bank).
PE[2]
J8
I/O
During power-on reset, PE[2] is latched by the rising edge of nPOR to
enable the PLL clocking mode.
DRIVE[0:1]
L9, L7
I/O
PWM drive outputs. These pins are inputs on power up to determine
what polarity the output of the PWM should be when active. Otherwise, these pins are always an output (See Table 91).
FB[0:1]
M9, P7
I
PWM feedback inputs
TDI
G4
I
JTAG data in
TDO
J4
O
JTAG data out
TMS
T2
I
JTAG mode select
PWM
Drives
Boundary
Scan
Test
Description
TCLK
T8
I
JTAG clock
nTRST
M15
I
JTAG async reset
nTEST[0:1]
K6, J9
I
Test mode select inputs are used in conjunction with the power-on
latched state of nURESET to select the various device test modes.
Table 90. External Signal Functions (Continued)
DS502PP2
143
CS89712
Function
Signal
Name
Signal
Description
MOSCIN
MOSCOUT
G9
H9
I
O
Main 3.6864 MHz oscillator for 18.432 MHz–73.728 MHz PLL
RTCIN
RTCOUT
R1
R2
I
O
Real-Time Clock 32.768 kHz oscillator
EECS
A6
O
EEPROM Chip Select - Active-high EEPROM select.
EESK
B6
O
EEPROM Serial Clock - clocks data in/out of the EEPROM.
EEDataOut
A5
O
EEDataIn
B5
I
EEPROM Data Out - used to send data to the EEPROM. Connects to the DI pin on the EEPROM. When TEST is low, this
pin becomes the output for the Boundary Scan Test.
EEPROM Data In - serial input used to receive data from the
EEPROM. Connects to the DO pin on the EEPROM.
EEDataIn is also used to sense the presence of the EEPROM.
This signal has a weak internal pullup.
TXD+/TXD-
A16,
A15
O
10BASE-T Transmit, Differential Output Pair - drives 10 Mb/s
Manchester-encoded data to the 10BASE-T transmit pair.
RXD+/RXD-
A12,
A11
I
RES
A10
I
XTAL[1:2]
A8, A7
10BASE-T Receive, Differential Input Pair - Differential input
pair receives 10 Mb/s Manchester-encoded data from the
10BASE-T receive pair.
Reference Resistor, Input - This input should be connected
to a 4.99KW ± 1% resistor needed for biasing of internal analog circuits.
Crystal, Input/Output - A 20 MHz crystal should be connected to these pins. If a crystal is not used, a 20 MHz signal
should connect to XTAL1 and XTAL2 should be left open.
LINKLED or
HC0
B9
O
LANLED
B8
O
Oscillators
Ethernet
EEPROM
10BASE-T
Interface
General
Ethernet Pins
No Connects
N/C
Link Good LED or software Controlled Output 0, Open
Drain Output- When the HCE0 bit of the Self Control register
(Register 15) is clear, this active-low output is low when the
CS89712 detects the presence of valid link pulses. When the
HC0E bit is set, the software may drive this pin low by setting
the HCBO in the Self Control register.
LAN Activity LED, Open Drain Output - During normal operation, this active-low output goes low for 6 ms whenever there
is a receive packet, a transmit packet, or a collision.
No connects should be left as no connects; do not connect to ground
Table 90. External Signal Functions (Continued)
Notes: 1. All deglitched inputs are via the 16.384 kHz clock. Each deglitched signal must be held active for at least
two clock periods. Therefore, the input signal must be active for at least ~125 µs to be detected cleanly.
2. The RTC crystal must be populated for the device to function properly.
144
DS502PP2
CS89712
5.2.1
Output Bi-Directional Pins
RUN
The RUN pin is looped back in to skew the address and data bus from each other.
Drive [0-1]
Drive 0 and 1 are looped back in on power up to determine what polarity the output of the PWM
should be when active.
DD[3:0]
DD[3:0] are looped back in on power up to enable the reading of the ID of some LCD modules.
Table 91. Output Bi-Directional Pins
Note: Output pins above are bi-directional to enable monitored output to provide accurate control of timing or duration
DS502PP2
145
CS89712
5.3 256 PBGA Package Dimensions
0.85 (0.034)
±0.05 (.002)
17.00 (0.669)
±0.20 (.008)
Pin 1 Corner
D1
0.40 (0.016)
±0.05 (.002)
15.00 (0.590)
±0.20 (.008)
30° TYP
Pin 1 Indicator
17.00 (0.669)
±0.20 (.008)
E1
15.00 (0.590)
±0.20 (.008)
4 Layer
0.56 (0.022)
±0.09 (0.004)
2 Layer
0.36 (0.014)
±0.09 (0.004)
TOP VIEW
SIDE VIEW
D
17.00 (0.669)
Pin 1 Corner
1.00 (0.040)
1.00 (0.040)
REF
E
16 15 14 13 12 11 10 9
8 7
6
5
4
1.00 (0.040)
REF
A
B
C
D
E
F
G
H
J
K
L
M
N
P
R
1.00 (0.040)
0.50
R
3 Places
3 21
17.00 (0.669)
BOTTOM VIEW
JEDEC #: MO-151
Ball Diameter: 0.50 mm ± 0.10 mm, package body 17 x 17 mm
Notes: 1. Dimensions are in millimeters (inches), and controlling dimension is millimeter.
2. Before designing with this device, contact Cirrus Logic for the latest package information.
146
DS502PP2
CS89712
6. ELECTRICAL/THERMAL INFO
6.1 Absolute Maximum Ratings
DC Core, PLL, and RTC Supply Voltage
2.9 V
DC I/O Supply Voltage (Pad Ring)
3.6 V
DC Pad Input Current
±10 mA/pin; ±100 mA cumulative
Storage Temperature, No Power
–40°C to +125°C
RECOMMENDED OPERATING CONDITIONS
DC core, PLL, and RTC Supply Voltage
2.5 V ± 0.2 V
DC I/O Supply Voltage (Pad Ring)
3.3V ± 0.165 V
DC Input / Output Voltage
0V – I/O supply voltage
Operating Temperature
Commercial 0°C to +70°C
6.2 DC Characteristics
All characteristics are specified at VDD = 3.3 volts and VSS = 0 volts over an operating temperature of 0° C to
+70° C for all frequencies of operation. The current consumption figures relate to typical conditions at 2.5 V core,
3.3V I/O, 18.432 MHz operation with the PLL enabled.
Parameter
Symbol
Min
CMOS input high voltage
VIH
CMOS input low voltage
Schmitt trigger negative going threshold
Max
Unit
1.7
VDD +
0.3
V
VDDC = 2.5 V
VDDIO = 3.3 V
VIL
-0.3
0.8
V
VDDC = 2.5 V
VDDIO = 3.3 V
VT-
0.8
1.2
(Typ)
V
0.4
Schmitt trigger hysteresis
Vhst
0.1
CMOS output high voltage
Output drive 1
Output drive 2
VOH
VDD –
0.2
2.5
2.5
CMOS output low voltage
Output drive 1
Output drive 2
VOL
(Note 1)
IIN
Output tri-state leakage current
(Notes 2 and 3)
IOZ
Input leakage current
Notes: 1.
2.
25
Typ
Conditions
V
VIL to VIH
V
V
V
IOH = 0.1 mA
OH = 4 mA
OH = 12 mA
0.3
0.5
0.5
V
V
V
IOL = –0.1 mA
OL = –4 mA
OL = –12 mA
10.0
µA
VIN = V DD or GND
100
µA
VOUT = VDD or GND
The leakage value given assumes that the pin is configured as an input pin but is not currently being driven. An
input pin not driven will have a maximum leakage of 1 µA. When the pin is driven, there will be no leakage.
Assumes buffer has no pull-up or pull-down resistors.
3. The leakage value given assumes that the pin is configured as an output pin but is not currently being
driven. An output pin not driven will have leakage between 25 µA and 100 µA. When the pin is driven,
there will be no leakage. Note that this applies to all output pins and all I/O pins configured as outputs.
DS502PP2
147
CS89712
DC CHARACTERISTICS (Continued)
Parameter
Input capacitance
Output capacitance
Transceiver capacitance
Startup current consumption
Symbol
CIN
COUT
CI/O
IDDstartup
Standby current consumption
Core, Osc, RTC @2.5 V, I/O @ 3.3 V
IDDstandby
Snooze current consumption
IDDsnooze
TBD
mA
IDDidle
TBD
mA
Idle current consumption
148
Min
Typ
8
8
8
Max
10.0
10.0
TBD
Unit
10.0
pF
pF
µA
µA
TBD
TBD
Conditions
pF
Initial 100 ms
from power up,
Cache disabled,
32 kHz oscillator not stable,
POR signal at
VIL, all other I/O
static, VIH = VDD
± 0.1 V, VIL =
GND ± 0.1 V
Just 32 kHz
oscillator running, Cache disabled, all other
I/O static, VIH =
VDD ± 0.1 V, VIL
= GND ± 0.1 V
Both oscillators
running, CPU
static, LCD from
oc-SRAM.
Both oscillators
running, CPU
static, Cache
disabled, LCD
refresh active,
VIH = VDD ±
0.1 V, VIL =
GND ± 0.1 V
DS502PP2
CS89712
DC CHARACTERISTICS (
Parameter
Operating current consumption (74 MHz)
Symbol
Min
Typ
Max
Unit
IDDoperating
Core/Osc/RTC @2.5 V, I/O @ 3.3 V
Ethernet active
90
TBD
mA
Operating power consumption (74 MHz)
270
TBD
mW
Ethernet XTAL1 Input Low Voltage
VIXH
-
0.2
-
V
Ethernet XTAL1 Input High Voltage
VIXH
-
1.5
-
V
XTAL1 Input Low Current
IIXL
-
-40
-
µA
XTAL1 Input High Current
IIXH
-
40
-
µA
Ethernet Port Power Supply Current while
Active 3.3V
IDD
-
65
-
mA
-
1.0
-
mA
Ethernet Port Software Suspend Mode Cur- IDDSWSUS
rent
Conditions
All system active,
running typical program, cache disabled, LCD inactive
see above
10 BaseT Transmitter Differential Output
Voltage (Peak)
VOD
2.2
-
2.8
Secondary side of
Transformer
Receiver Normal Squelch Level (Peak)
VISQ
300
-
525
Primary side of
Transformer
Receiver Low Squelch Level (LoRxSquelch
bit set)
VSQL
125
-
290
Primary side of
Transformer
VDDstandby
TBD
Standby supply voltage
V
Minimum standby
voltage for state
retention and RTC
operation only
Notes: 4. Power dissipation values can be derived by multiplying the IDD current by 2.5 V Core/OSC or 3.3V I/O.
5. The RTC of the CS89712 should be brought up at room temperature. The RTC OSC will NOT function
properly if it is brought up at –40°C. Once operational, it will continue to operate down to –40°C.
6. A typical design will provide 3.3 V to the I/O supply (i.e., VDDIO), and 2.5 V to the remaining logic. This
is to allow the I/O to be compatible with 3.3 V powered external logic (i.e., 3.3 V SDRAMs).
7. Pull-up current = 50 µA typical at VDD = 3.3 volts.
DS502PP2
149
CS89712
6.3 AC Characteristics
These are specified at VDD = 3.3 volts and VSS = 0 volts over an operating temperature of 0°C to +70°C. The timing
values are referenced to 1/2 VDD.
Parameter
Falling CS to data bus Hi-Z
Note:
150
Symbol
t1
18/36 MHz
Min
Max
0
25
Units
ns
Address change to valid write data
t2
0
35
ns
DATA in to falling EXPCLK setup time
t3
18
—
ns
DATA in to falling EXPCLK hold time
t4
0
—
ns
EXPRDY to falling EXPCLK setup time
t5
18
—
ns
Falling EXPCLK to EXPRDY hold time
t6
0
50
ns
Rising nMWE to data invalid hold time
t7
5
—
ns
Sequential data valid to falling nMWE setup time
t8
–10
10
ns
Row address to falling nRAS setup time
t9
5
-
ns
Falling nRAS to row address hold time
t10
25
-
ns
Column address to falling nCAS setup time
t11
2
-
ns
Falling nCAS to column address hold time
t12
25
-
ns
Write data valid to falling nCAS setup time
t13
2
-
ns
Write data valid from falling nCAS hold time
t14
50
-
ns
LCD CL2 low time
t15
80
3,475
ns
LCD CL2 high time
t16
80
3,475
ns
LCD falling CL[2] to rising CL[1] delay
t17
0
25
ns
LCD falling CL[1] to rising CL[2]
t18
80
3,475
ns
LCD CL[1] high time
t19
80
3,475
ns
LCD falling CL[1] to falling CL[2]
t20
200
6,950
ns
LCD falling CL[1] to FRM toggle
t21
300
10,425
ns
LCD falling CL[1] to M toggle
t22
–10
20
ns
LCD rising CL[2] to display data change
t23
–10
20
ns
Falling EXPCLK to address valid
t24
—
5
ns
Data valid to falling nMWE for non sequential access only
t25
5
—
ns
SSICLK period (slave mode)
t31
0
512
kHz
SSICLK high
t32
925
1025
ns
SSICLK low
t33
925
1025
ns
SSICLK rise / fall time
t34
7
ns
SSICLK rising to RX and / or TX frame sync
t35
528
ns
SSICLK rising edge to frame sync low
t36
448
ns
SSICLK rising edge to TX data valid
t37
SSIRXDA data set-up time
t38
SSIRXDA data hold time
SSITXFR and / or SSIRXFR period
80
ns
30
ns
t39
40
ns
t40
750
ns
All SDRAM 36 MHz timings are for SDRAM operation.
The values for 36 MHz include 1 wait state, the 18 MHz values have 0 wait states.
DS502PP2
CS89712
TIMING CHARACTERISTICS
Characteristics
Symbol
18 MHz
Min
Note:
36 MHz
Max
Min
Units
Max
Negative strobe (nCS[0:5]) zero
wait state read access time
tnCSRD
TBD
TBD
TBD
Negative strobe (nCS[0:5]) zero
wait state write access time
tnCSWR
TBD
TBD
TBD
Sequential expansion burst mode
read access time
tEXBST
TBD
TBD
TBD
SDRAM cycle time
tRC
TBD
-
TBD
TBD
Access time from RAS
tRAC
TBD
-
TBD
TBD
RAS precharge time
tRP
TBD
-
TBD
TBD
CAS pulse width
tCAS
TBD
-
TBD
TBD
CAS precharge in page mode
tCP
TBD
-
TBD
TBD
Page mode cycle time
tPC
TBD
-
TBD
TBD
CAS set-up time for auto refresh
tCSR
TBD
-
TBD
TBD
RAS pulse width
tRAS
TBD
-
TBD
TBD
All SDRAM 36 MHz timings are for SDRAM operation.
The values for 36 MHz assume 1 wait state, the 18 MHz values have 0 wait states.
DS502PP2
151
CS89712
eXPCLK
tNCSRD
nCS[5:0]
nMOE
A[27:0]
WORD
t1
tADRD
tPCSRD
D[31:0]
t3
t4
Data in
Bus held
t5
t3
t4
Data in
t6
eXPRDY
Notes: 1. tnCSRD = 50 ns at 36.864 MHz
70 ns at 18.432 MHz
Maximum values for minimum wait states. This time can be extended by integer multiples of the clock
period (27 ns at 36 MHz or 54 ns at 18.432 MHz), by either driving EXPRDY low and/or by
programming a number of wait states. EXPRDY is sampled on the falling edge of EXPCLK before
the data transfer. If low at this point, the transfer is delayed by one clock period where EXPRDY is
sampled again. EXPCLK need not be referenced when driving EXPRDY, but is shown for clarity.
2. Consecutive reads with sequential access enabled are identical except that the sequential access
wait state field is used to determine the number of wait states, and no idle cycles are inserted
between successive non-sequential ROM/expansion cycles. This improves performance so the
SQAEN bit should always be set where possible.
3.
tnCSRD = tADRD = tPCSRD
4. When the CS89712 device implements consecutive reads(e.g., use of the LDM instruction),
regardless of the state of the SQAEN bit, the signals nMOE and nCSx will always remain low through
the entire multi-read access. They will not toggle in-between each different address access. In order
to have these signals toggle, single access read instructions (e.g., LDR) must be used.
Figure 24. Consecutive Memory Read Cycles with Minimum Wait States
152
DS502PP2
CS89712
EXPCLK
nCS[5:0]
nMOE
A[27:4]
tEXBST
A[3:0]
0
tEXBST
4
8
WORD
t1
tEXRD
D[31:0]
t3
t4
Data in
Bus held
t5
t4
t3
Data in
t3
t4
Data in
t6
EXPRDY
Notes:
1.tEXBST = 35 ns at 36.864 MHz
35 ns at 18.432 MHz
(Value for 36.864 MHz assumes 1 wait state.)
Maximum values for minimum wait states. This time can be extended by integer multiples of the
clock period (27 nsec at 36 MHz or 54 nsec at 18.432 MHz), by either driving EXPRDY low and/or
by programming a number of wait states. EXPRDY is sampled on the falling edge of EXPCLK before
the data transfer. If low at this point, the transfer is delayed by one clock period where EXPRDY is
sampled again. EXPCLK need not be referenced when driving EXPRDY, but is shown for clarity.
2. Consecutive reads with sequential access enabled are identical except that the sequential access
wait state field is used to determine the number of wait states, and no idle cycles are inserted
between successive non-sequential ROM/expansion cycles. This improves performance so the
SQAEN bit should always be set where possible.
Figure 25. Sequential Page Mode Read Cycles with Minimum Wait States
DS502PP2
153
CS89712
eXPCLK
tnCSWR
nCS[5:0]
t8
tADWR
nMWE
A[27:0]
WORD
t2
D[31:0]
Bus held
t7
t2
Write data
Write data
t6
t5
nEXPRDY
Notes: 1. tnCSWR = 35 nsec at 36.864 MHz, 70 ns at 18.432 MHz
Maximum values for minimum wait states. This time can be extended by integer multiples of the
clock period (27 nsec at 36 MHz or 54 nsec at 18.432 MHz), by either driving EXPRDY low and/or
by programming a number of wait states. EXPRDY is sampled on the falling edge of EXPCLK
before the data transfer. If low at this point, the transfer is delayed by one clock period where
EXPRDY is sampled again. EXPCLK need not be referenced when driving EXPRDY, but is shown
for clarity.
2. Consecutive reads with sequential access enabled are identical except that the sequential access
wait state field is used to determine the number of wait states, and no idle cycles are inserted
between successive non-sequential ROM/expansion cycles. This improves performance so the
SQAEN bit should always be set where possible.
3. Zero wait states for sequential writes is not permitted for memory devices which use nMWE pin, as
this cannot be driven with valid timing under zero wait state conditions.
Figure 26. Consecutive Memory Write Cycles with Minimum Wait States
154
DS502PP2
CS89712
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
CLK
CKE
1 dev
nCS
1 dev
CAS lat 2
nRAS /
nCAS / nWE
NOP
ACT
NOP
READ
NOP
NOP
NOP
NOP
tRCD
NOP
NOP
NOP
(ACT)
tRP
tRAS
auto precharge
tRC
DQM
DI0
DQ
Bank sel
bank
A10
(prech sel)
row
addr
row
1.
2.
3.
4.
5.
DI1
DI2
DI3
bank
col
tRCD (delay time ACT to READ/WRITE command) = 30 ns or 2 cycles at 36 MHz.
tRP (PRE to ACT command period) = 30 ns or 2 cycles at 36 MHz.
tRAS (ACT to PRE command period) = 60 ns or 3 cycles at 36 MHz.
tRC (ACT to REF/ACT command period [operation]) = 90 ns or 4 cycles at 36 MHz.
For SDCAS latency 3, there will be an extra cycle between T4 and T5.
6. For CAS latency 3, there will be an extra cycle between T4 and T5.
Figure 27. SDRAM Read Cycles CAS Latency = 2
DS502PP2
155
CS89712
T0
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
T11
CLK
CKE
1 dev
nCS
1 dev
CAS lat 3
nRAS /
nCAS / nWE
NOP
ACT
NOP
READ
NOP
NOP
NOP
NOP
NOP
NOP
tRCD
NOP
NOP
(ACT)
tRP
tRAS
auto precharge
tRC
DQM
DI0
DQ
Note:
Bank sel
bank
A10
(prech sel)
row
addr
row
DI1
DI2
DI3
bank
col
tRC1 (REF to REF/ACT command period [refresh]) = 90 ns or 4 cycles at 36 MHz.
Figure 28. SDRAM Read Cycles CAS Latency = 3
T0
T1
T2
T3
T4
T5
T6
T7
CLK
CKE
nCS
nRAS /
nCAS / nWE
NOP
1 dev
1 dev
ACT
NOP WRITE NOP
NOP
NOP
tRCD
NOP
tDPL
tRAS
NOP
(ACT)
tRP
auto precharge
tRC
DQM
DO0
DQ
Note:
Bank sel
bank
A10
(prech sel)
row
addr
row
DO1
DO2
DO3
bank
col
tDPL (data in to PRE command period command) = 10 ns or 1 cycle at 36 MHz.
Figure 29. SDRAM Write Cycles
156
DS502PP2
CS89712
T0
T1
T2
T3
T4
CLK
CKE
all
nCS
nRAS /
nCAS / nWE
NOP
REF
NOP
tRP
NOP
NOP
(ACT)
tRC1
auto precharge
DQM
DQ
Bank sel
A10
(prech sel)
addr
Figure 30. SDRAM Refresh Cycles
t20
t15
t16
CL[2]
t17
t19
t18
t21
CL[1]
FRM
t22
M
t23
DD[3:0]
Notes: 1. The figure shows the end of a line.
2. If FRM is high during the CL[1] pulse, this marks the first line in the display.
3. CL[2] low time is doubled during the CL[1] high pulse
Figure 31. LCD Controller Timings
DS502PP2
157
CS89712
DI9
DI8
DI1
DI0
DO1
DO0
ADCCLK
(SCLK)
nADCCS
(nRFS/TFS)
ADCIN
(Din)
DI7
DI6
DI5
DI4
DI3
DI2
ADCOUT
(Dout)
DO9
DO8
Figure 32. SSI1 Interface for AD7811/2
W
W
W
SSICLK
W
W
SSI RX/TXFR
W
W
'
SSITXDA
W
SSIRXDA
'
'
'
'
'
'
W
'
Figure 33. SSI2 Interface Timings
158
DS502PP2
CS89712
ETHERNET TIMING CHARACTERISTICS
Parameter
Symbol
Min
Typ
Max
Unit
Allowable Received Jitter at Bit Cell Center
tTRX1
-
-
±13.5
ns
Allowable Received Jitter at Bit Cell Boundary
tTRX2
-
-
±13.5
ns
Carrier Sense Assertion Delay
tTRX3
-
540
-
ns
Invalid Preamble Bits after Assertion of Carrier Sense
tTRX4
1
-
2
bits
Carrier Sense Deassertion Delay
tTRX5
-
270
-
ns
First Transmitted Link Pulse after Last Transmitted Packet
tLN1
8
16
24
ms
Time Between Transmitted Link Pulses
tLN2
8
16
24
ms
Width of Transmitted Link Pulses
tLN3
60
100
200
ns
Minimum Received Link Pulse Separation
tLN4
2
-
7
ms
Maximum Received Link Pulse Separation
tLN5
25
-
150
ms
Last Receive Activity to Link Fail (Link Loss Timer)
tLN6
50
-
150
ms
EESK Setup time relative to EECS
tSKS
100
-
-
ns
EECS Setup time wrt ↑ EESK
tCCS
250
-
-
ns
tDIS
250
-
-
ns
EEDataOut Hold time wrt ↑ EESK
tDIH
500
-
-
ns
EEDataIn Hold time wrt ↑ EESK
tDH
10
-
-
ns
EECS Hold time wrt ↓ EESK
tCSH
100
-
-
ns
Min EECS Low time during programming
tCS
1000
-
-
ns
10BASE-T Receive
10BASE-T Link Integrity
Ethernet EEPROM
EEDataOut Setup time wrt ↑ EESK
RXD±
tTRX1
tTRX3
tTRX2
tTRX4
tTRX5
Carrier Sense (internal)
Figure 34. 10BASE-T Receive
DS502PP2
159
CS89712
t LN1
t LN2
t LN3
TXD±
t LN4
t LN5
RXD±
t LN6
LINKLED
Figure 35. 10BASE-T Link Integrity
EESK
t SKS
EECS
t CSS
t CSH
t CS
t DIH
t DIS
EEData Out
t DH
EEData In
(Read)
Figure 36. EEPROM
160
DS502PP2
CS89712
ETHERNET QUARTZ CRYSTAL REQUIREMENTS (If a 20 MHz quartz crystal is used, it
must meet the following specifications)
Parameter
Min
Typ
Max
Unit
-
20
-
MHz
Resonant Frequency Error (CL = 18 pF)
-50
-
+50
ppm
Resonant Frequency Change Over Operating Temperature
-40
-
+40
ppm
Crystal Capacitance
-
-
18
pF
Motional Crystal Capacitance
-
0.022
-
pF
Series Resistance
-
-
50
Ohm
Shunt Capacitance
-
-
7
pF
Parallel Resonant Frequency
1:2.5
TXD +
TD +
Rt
1
560 pF
TXD -
Rt
TD -
0.01 µF
2
RJ45
RD +
RXD+
+
-
RXD-
0.01 µF
3
Rr
Rr
1:1
RD -
6
Notes: 1. If a center tap transformer is used on the RXD+ and RXD- inputs, replace the pair of Rr resistors with
a single 2xRr resistor.
2. The Rt and Rr resistors are ±1% tolerance.
3. The CS89712 Ethernet port supports 100 W unshielded twisted pair cables. The proper values of Rt
and Rr, for a given cable impedance, are shown below:
Cable Impedance (Ω)
Rt (Ω)
Rr (Ω)
100
8.2
49.9
Figure 37. 10Base-T Wiring
DS502PP2
161
CS89712
6.4 I/O Buffer Strength & Characteristics
All I/O buffers on the CS89712 are CMOS threshold input bidirectional buffers except the oscillator
and power pads. For signals that are nominally inputs, the output buffer is only enabled during pin
test mode. All output buffers are three stated during
system (hi-Z) test mode. All buffers have a standard CMOS threshold input stage (apart from the
Schmitt-triggered inputs) and CMOS slew-rate-
controlled output stages to reduce system noise.
Table 92 defines the I/O buffer output characteristics which will apply across the full range of temperature and voltage (i.e., these values are for
3.3 V, +70° C).
All propagation delays are specified at 50% VDD to
50% VDD, all rise times are specified as 10% VDD
to 90% VDD and all fall times are specified as 90%
VDD to 10% VDD.
Buffer Type
Drive Current
Propagation
Delay (Max)
Rise Time
(Max)
Fall Time
(Max)
Load
Address outputs
±12 mA
5
6
6
50 pF
Non-address outputs
±4 mA
7
14
14
50 pF
Table 92. I/O Buffer Output Characteristics
162
DS502PP2
CS89712
7. ORDERING INFORMATION
The order number for the device is:
CS89712 — CB
Package Type:
B = Plastic Ball Grid Array (17 mm x 17 mm)
Part Number
Temperature Range:
C = Commercial
Product Line:
Crystal
Note: Contact Cirrus Logic for up-to-date information on revisions. Go to the Cirrus Logic Internet site at
http://cirrus.com/corporate/contacts to find contact information for your local sales representative.
DS502PP2
163
CS89712
Appendix A - Terms
Acronym
Definition
LineST
Ethernet Line Status.
Acronyms, abbreviations, units of measurement,
and conventions used in this document.
LLC
Logical Link Control.
LQFP
Low Profile Quad Flat Pack.
Acronyms and Abbreviations
MAC
Media Access Control.
Table 93 lists abbreviations and acronyms.
MAU
Medium Attachment Unit.
MIB
Management Information Base.
Acronym
Definition
MMU
Memory Management Unit.
A/D
Analog-to-Digital.
PBGA
Plastic Ball Grid Array.
ADC
Analog-to-Digital Converter.
PDA
Personal Digital Assistant.
BufCFG
Buffer Configuration.
PIA
Peripheral Interface Adapter.
BufEvent
Buffer Event.
PLL
Phase Locked Loop.
BusCTL
Bus Control.
PSU
Power Supply Unit.
BusST
Bus State.
p/u
Pull-Up Resistor.
CODEC
Coder / Decoder.
RTC
Real-Time Clock.
CRC
Cyclic Redundancy Check.
RxCFG
Receive Configuration.
CS
Carrier Sense.
RxCTL
Receive Control.
CSMA/CD
Carrier Sense Multiple Access with Collision Detection.
RxEvent
Receive Event.
SelfCTL
Self Control.
DA
Destination Address.
D/A
Digital-to-Analog.
SA
Source or System Address.
ENDEC
Manchester Encoder/Decoder.
SelfST
Self Status.
SFD
Start-of-Frame Delimiter.
EOF
End-of-Frame.
EPB
Embedded Peripheral Bus.
SIR
Slow (9.6 – 115.2 kbps) Infrared.
FCS
Frame Check Sequence.
SNMP
Simple Network Management Protocol.
SOF
Start-of-Frame.
FDX
Full Duplex.
GPIO
General Purpose I/O.
SQE
Signal Quality Error.
SSI
Synchronous Serial Interface.
IA
Individual Address.
ICT
In Circuit Test.
TAP
Test Access Port.
TestCTL
Test Control.
IPG
Inter-Packet Gap.
IR
Infrared.
TLB
Translation Lookaside Buffer.
IrDA
Infrared Data Association.
TxCFG
Transmit Configuration.
ISQ
Interrupt Status Queue.
TxCMD
Transmit Command.
JTAG
Joint Test Action Group.
TxEvent
Transmit Event.
Line CTL
Ethernet Line Control.
UTP
Unshielded Twisted Pair.
Table 93. Acronyms and Abbreviations (Continued)
Table 93. Acronyms and Abbreviations
164
DS502PP2
CS89712
Units of Measurement
Symbol
Unit of Measure
°C
degree Celsius
Hz
hertz (cycle per second)
kbits/s
kilobits per second
kbyte
kilobyte (1,024 bytes)
kHz
kilohertz
kΩ
kilohm
Mbps
megabits (1,048,576 bits) per second
Mbyte
megabyte (1,048,576 bytes)
MHz
megahertz (1,000 kilohertz)
µA
microampere
µF
microfarad
µW
microwatt
µs
microsecond (1,000 nanoseconds)
mA
milliampere
mW
milliwatt
ms
millisecond (1,000 microseconds)
ns
nanosecond
V
volt
W
watt
Ethernet port Definitions
•
Causes the Ethernet port to take a certain action
once when the bit is set. To cause the action
again, the software must rewrite a "1".
•
•
“TBD” indicates values “to be determined,” “n/a”
designates “not available”, “n/c” indicates a “no
connect. pin” and “dc” means “don’t care”.
DS502PP2
Committed Transmit Frame
A transmit frame is "committed" after software
has issued a Transmit Command, and the Ethernet port has reserved buffer space and notified
the software that it is ready for transmit.
•
Cyclic Redundancy Check
The method used to compute the 32-bit frame
check sequence.
•
Event or Interrupt Event
Refers to something that can trigger an interrupt. Items that are considered "Events" are reported in the three Event registers (RxEvent,
TxEvent, or BufEvent) and in two counteroverflow bits (RxMISS and TxCOL).
General Conventions
Registers are referred to by acronym, as listed in
the tables on the previous page, with bits listed in
brackets MSB-to-LSB separated by a colon (:) (for
example, CODR[7:0]), or LSB-to-MSB separated
by a hyphen (for example, CODR[0–2]).
Committed Receive Frame
A receive frame is "committed" after the frame
has been buffered by the Ethernet port, and a receive interrupt has been generated.
Table 94. Units of Measurement
Hexadecimal numbers are presented with all letters
in uppercase and a lowercase “h” appended or with
a 0x at the beginning, for example, 0x14 and
03CAh. Binary numbers are enclosed in single
quotation marks when in text (for example, ‘11’
designates a binary number). Numbers not indicated by an “h”, 0x or quotation marks are decimal.
Act-Once bit
•
Frame
The portion of a packet from the DA to the
FCS. This includes the Destination Address
(DA), Source Address (SA), Length field, Data
field, pad bits (if necessary), and Frame Check
Sequence (FCS, also called CRC). "Frame data" refers to all data from the DA to the FCS to
be transmitted, or that has been received.
•
Frame Check Sequence
The 32-bit field at the end of a frame that contains the cyclic redundancy check result.
•
Individual Address
The specific Ethernet address assigned to a device attached to the Ethernet media.
165
CS89712
•
Inter-Packet Gap
•
Time interval between packets on the Ethernet.
Minimum interval is 9.6 ms.
•
Moving frame data across the memory bus
from the Ethernet port RAM to system RAM.
During receive operations, only frame data are
transferred (preamble and SFD are stripped off
by the CS89712’s MAC engine). The FCS may
or may not be transferred, depending on the
configuration. Transfers are counted in bytes.
Jabber
A condition that results when an Ethernet node
transmits longer than between 20 ms and
150 ms.
•
•
•
Packet
•
Transmit Collision
The entire serial string of bits transmitted over
an Ethernet network. This includes the preamble, Start-of-Frame Delimiter, Destination Address, Source Address, Length field, Data field,
pad bits (if necessary), and Frame Check Sequence (FCS, also called CRC). A packet is a
frame plus the Preamble and SFD.
•
Slot Time
These have meaning only at the end of a term:
Time required for an Ethernet Frame to cross a
maximum length Ethernet network. One Slot
Time equals 512 bit times.
A
CMD
CFG
CTL
Dis
E
h
iE
ST
Suspend
Used to conserve power. When in Suspend
mode, the Ethernet port can be awakened only
by software command.
166
Transfer
The receive inputs, RXD+/RXD- (10BASE-T)
are active while a packet is being transmitted.
Transmit Request
A Transmit Request is issued by the software to
initiate the start of a new packet transmission.
Suffixes Specific to the Ethernet port
Accept
Command
Configure
Control
Disable
Enable
Indicates the number is hexadecimal
Interrupt Enable
Status
DS502PP2
CS89712
Appendix B: Boot Code
00000000
uart_boot_base
00000000 E3A0C102
MOV
00000004
r12, #HwRegisterBase ; R12 = 0x80000000
00000004 E3A08201
MOV r8, #InternalRamBase ; R8 = 0x10000000
00000008 E2889B02
ADD r9, r8, #ImageSize ; R9 = 0x10000800
0000000C
0000000C
;;; The remaining code is functionally identical to the 7111 boot code
0000000C
0000000C
;;; First, initialize HW control of UART
0000000C
0000000C 00000480 Hw_UARTDR1 EQU 0x0480
0000000C
0000000C 000004C0 Hw_UBRLCR1 EQU 0x04c0
0000000C 00000017 Hw_BR9600 EQU 0x00000017 ; 9600 baud divisor = 23
0000000C 0000000B Hw_BR9600_13 EQU 0x0000000b ; 9600 baud divisor = 11
0000000C 00060000 Hw_WRDLEN8 EQU 0x00060000
0000000C
0000000C E3A00C01
MOV r0, #Hw_UART1EN ; Enable UART
00000010 E58C0100
STR r0, [r12, #Hw_SYSCON]
00000014
00000014 E28C1D45
ADD r1, r12, #Hw_SYSFLG2 ; (was LDR, ADD in 7111 code)
00000018 E5917000
LDR r7, [r1] ; R7 = SYSFLG2
0000001C
0000001C E3170040
TST r7, #Hw_CKMODE
00000020 13A0000B
MOVNE r0, #Hw_BR9600_13 ; Load 13 MhZ value if bit set
00000024 03A00017
MOVEQ r0, #Hw_BR9600 ; If not set, load other divisor
00000028 E3800806
ORR r0, r0, #Hw_WRDLEN8 ; Insert 8-bit character mode
0000002C
0000002C E58C04C0
STR r0, [r12, #Hw_UBRLCR1]
00000030
00000030 0000003C StartFlag EQU ‘<’
00000030 0000003E EndFlag EQU
‘>’
00000030
00000030
;;; Send ready signal
00000030 E3A0003C
MOV r0, #StartFlag
00000034 E58C0480
STR r0, [r12, #Hw_UARTDR1]
00000038
00000038
;;; Receive the data
00000038
;;; Store bytes at R9 address, stop loop when R8 == R9
00000038
;;; Leaves R8 set to 0x10000800
00000038
00000038
;;; Wait for byte to be available
00000038
00000038
uart_ready_loop
00000038 E59C1140
LDR r1, [r12, #Hw_SYSFLG] ; Spin, if Rx FIFO is empty
0000003C E3110501
TST r1, #Hw_URXFE1
00000040 1AFFFFFC
BNE uart_ready_loop
00000044
00000044
;;; Read the data, store it, and accumulate checksum
00000044 E59C0480
LDR r0, [r12, #Hw_UARTDR1] ; Read data
00000048 E4C80001
STRB r0, [r8], #1 ; Save it in memory
DS502PP2
167
CS89712
0000004C E1580009
CMP r8, r9
00000050 BAFFFFF8
BLT uart_ready_loop ; Do more if end of buffer not reached
00000054
00000054
;;; All received, send end flag
00000054
00000054 E3A0003E
MOV r0, #EndFlag
00000058 E5CC0480
STRB r0, [r12, #Hw_UARTDR1] ; Send reply
0000005C
0000005C
0000005C
0000005C
;;; Having loaded all the bytes, do the right thing to finish.
0000005C
;;;
0000005C
0000005C E55807FD
LDRB r0, [r8, #(3-ImageSize)]
00000060 E35000FF
CMP r0, #BootImageFlagByte
00000064
00000064
00000064 01A0F00E
MOVEQ pc, r14 ; Return to caller for secure image
00000068
00000068
00000068
00000068
00000068 E28CAB09
ADD r10, r12, #WWWWWWWWWW ; R10 = 0x80002400 (also XXXXXX)
0000006C E58AC080
STR r12, [r10, #(ZZZZZZZZZZZ - YYYYYYYYYY)]
00000070 E248FB02
SUB pc, r8, #ImageSize ; Branch to 0x10000000
00000074
00000074
00000074
;;; Put a checksum here so this part can be verified, too.
00000074
;;; Have to pad the tail out to 31 words, then the checksum.
00000074
00000074 0000000000
ALIGN 128, -4 ; Align just before end of 128-byte tail
0000007C
uart_checksum
0000007C 436B74AB
DCD 0x436b74ab
00000080
00000080
ASSERT (. - start_of_rom) = 640 ; Check that it’s in the right place
00000080
00000080
END
168
DS502PP2
• Notes •