West Bridge™ : Antioch™ USB/Mass
Storage Peripheral Controller
1.0 Features
• SLIM™ Architecture, allowing simultaneous and
independent data paths between Processor & USB and
between USB & Mass Storage
• High-Speed USB at 480 Mbps
— USB 2.0 compliant
Memory-mapped interface to main processor
DMA slave support
Ultra low-power, 1.8V core operation
Low Power Modes
Small footprint, 6x6mm VFBGA
Selectable Clock Input Frequencies
— 19.2 MHz, 24 MHz, 26 MHz, 48 MHz
— Integrated USB 2.0 transceiver, smart Serial Interface
2.0 Applications
— 16 programmable endpoints
• Mass Storage device support
— NAND flash: x8 or x16, SLC
— Full NAND management (ECC, wear-leveling)
Cellular Phones
Portable Media Players
Personal Digital Assistants
Digital Cameras
Portable Video Recorder
Figure 1-1. West Bridge Antioch Block Diagram
West Bridge Antioch
Control Registers
8051 MCU
Access Control
Mass Storage Interface
3.0 Functional Overview
3.1The SLIM™ architecture
The Simultaneous Link to Independent Multimedia (SLIM)
architecture allows three different interfaces (the P-port, the
S-port and the U-port) to connect to one-another independently.
Cypress Semiconductor Corporation
With this architecture, connecting a device using Antioch to a
PC through USB does not disturb any of the functions of the
device, which can still access Mass storage at the same time
the PC is synchronizing with the main processor.
The SLIM architecture enables new usage models, in which a
PC can access a Mass storage device independent of the
main processor, or enumerate access to both the mass
storage and the main processor at the same time.
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In a handset, this typically enables the user to use the phone
as a thumb drive, or download media files to the phone while
still having full functionality available on the phone, or even
use the same phone as a modem to connect the PC to the
3.2 8051 Microprocessor
The 8051 microprocessor embedded in Antioch does basic
transaction management for all the transactions between the
P-Port, the S-Port, and the U-Port. The 8051 does not reside
in the data path; it manages the path. The data path is
optimized for performance. The 8051 executes firmware that
supports NAND, SD, and MMC devices at the S-Port. For the
NAND device, the 8051 firmware follows the Smart Media
algorithm to support:
• Physical to Logical Management
• ECC Correction support
• Wear Leveling
• NAND Flash bad blocks handling
3.2 Configuration and Status Registers
The West Bridge Antioch device includes configuration and
status registers that are accessible as memory-mapped
registers through the processor interface. The configuration
registers allow the system to specify certain behavior of
Antioch. For example, it can mask certain status registers from
raising an interrupt. The status registers convey various status
of Antioch, such as the addresses of buffers for read operations.
the external processor only deals with the buffers to access a
multitude of storage devices connected to Antioch.
In the Interrupt mode, Antioch communicates important buffer
status changes to the external processor using an interrupt
signal. The external processor then polls Antioch for the
specific buffers ready for read or write, and it performs the
appropriate read or write operations via the processor
3.4 USB Interface (U-Port)
In accordance with the USB 2.0 specification, Antioch can
operate in Full-Speed USB mode in addition to High-Speed
USB. The USB interface consists of the USB transceiver. The
USB interface can access and be accessed by both the P-Port
and the S-Port.
The Antioch USB interface supports programmable
3.5 Mass Storage Support (S-Port)
The S-Port can be configured in two different modes, either
simultaneously supporting an SD/MMC+ port and a x8 NAND
port, or supporting a unique x16 NAND access port. The
NANDCFG pin is used to set the configuration of the S-Port to
be either 16-bit NAND or 8-bit NAND and SD/MMC. The 16-bit
interface can only be used when there is no other mass
storage device connected to the S-Port.
Antioch also includes two chip enables, NAND_CE# and
NAND_CE2#, which allow two different NANDs to be alternately accessed.
3.3 Processor Interface (P-Port)
3.5.1NAND Port (S-Port)
Communication with the external processor is realized through
a dedicated processor interface. This interface supports both
synchronous and asynchronous SRAM-mapped memory
accesses. This ensures straightforward electrical communications with the processor, which also may have other devices
connected on a shared memory bus. Asynchronous accesses
can reach a bandwidth of up to 66.7 MBps. Synchronous
accesses can be performed at 33 MHz across 16 bits for up to
66.7 MBps bandwidth.
Antioch, as part of its mass storage management functions,
can fully manage a NAND device. The embedded 8051
manages the actual reading and writing of the NAND, along
with its required protocols. It performs standard NAND
management functions such as ECC and wear leveling.
The memory address is decoded to access any of the multiple
endpoint buffers inside Antioch. These endpoints serve as
buffers for data between each pair of ports, for example,
between the processor port and the USB port. The processor
writes and reads into these buffers via the memory interface.
Access to these buffers is controlled by either using a DMA
protocol or using an interrupt to the main processor. These two
modes are configurable by the external processor.
As a DMA slave, Antioch generates a DMA request signal to
signify to the main processor that a specific buffer is ready to
be read from or written to. The external processor monitors this
signal and polls Antioch for the specific buffers ready for read
or write. It then performs the appropriate read or write operations on the buffer through the processor interface. This way,
SLC NAND devices are supported on all devices in the Antioch
family. Write performance for connecting to a single SLC
NAND is up to 9 MB/s, while read performance is up to 13
3.5.2SD/MMC Port (S-Port)
When Antioch is configured via NANDCFG to support
MMC/SD, this interface supports:
• The Multimedia Card-System Specification, MMCA
Technical Committee, Version 4.1
• SD Memory Card Specification - Part 1, Physical Layer
Specification, SD Group, Version 1.10, October 15, 2004.
West Bridge Antioch provides support for 1-bit and 4-bit SD
cards, as well as 1-bit, 4-bit and 8-bit MMC, and MMC+. For
the SD, MMC/MMC Plus, this block supports one card for one
physical bus interface.
Antioch supports SD commands including the multi-sector
program command that will be handled by the API.
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