AccessRunner ADSL-USB Modem Device Set Data Sheet
ARM Processor
Host
Interface
RAM
ROM
Control Logic
GPIO
External
Memory
Controller
(EMC)
SDRAM
or SRAM
ADSL
ADSL
Interface
Data Pump
and AFE
EEPROM
Interface
EEPROM
USB
USB
Interface
100427 F2-1_BD_P5200
Figure 2-1. P5200 UIC Block Diagram
Host Interface
The Host Interface is a 16-bit data and 21-bit address bus used for control of the ADSL Data Pump.
ADSL Interface
The ADSL Interface is responsible for data transfer to and from the ADSL Data Pump and the setup of the AFE.
USB Interface
The USB Interface is responsible for data transfer to and from the USB, by extracting clock and data from the USB cable. It
also handles the front end functions of the USB protocol such as Sync Field Identification, NRZI-NRZ Conversion, Bit
Stripping and Stuffing, and CRC functions. Additionally, the USB port converts the serial packet to 8-bit parallel data. Control
transfers addressed to End Point Zero are handled by the USB port.
LED Interface
GPIO are used to support the following LED signals: Power, Ready, Showtime, TXD, and RXD.
EEPROM Interface
A 2-wire serial EEPROM is used to store USB device, configuration, interface, and endpoint descriptors. Device descriptors
include Vendor ID, Product ID, Device Release Number, Manufacturer Name, Product Name, and Serial Number. Both 4196
bit and 2048 bit EEPROMs are supported. The EEPROM speed must be capable of 400 kHz clock frequency.
A typical 4196 bit (512 x 8) EEPROM that meets P5200 UIC requirements is the Fairchild M24C04M8 or equivalent.
A typical 2048 bit (256 x 8) EEPROM that meets P5200 UIC requirements is the Fairchild M24C02M8 or equivalent.
General Purpose Input/Output Interface
Most General Purpose Input/Output (GPIO) pins are programmed for dedicated system functions or reserved for test or
growth functions and are not available for user assignment. Each GPIO pin is controlled individually for input/output direction.
All GPIO pins can serve as external interrupt inputs.
Conexant
100427B
2-3
CONEXANT [ CONEXANT SYSTEMS, INC ]
