ADSP-21MOD870-110 查看數據表（PDF） - Analog Devices

零件编号

产品描述 (功能)

生产厂家

ADSP-21MOD870-110

Internet Gateway Processor Software

Analog Devices 

SOFTWARE INTERFACE

Analog Devices provides sample C code for the software inter-

face to the ADSP-21mod870-110. The software interface en-

compasses the following four areas—download, control interface,

data interface and modem statistics.

Download

The IDMA port on the ADSP-21mod870-110 contains an

autoincrementing address generator. The host writes the start-

ing address of the transfer and then writes the first word of

data. After the first write, the IDMA address generator auto-

matically increments; the host writes the next data word and

the IDMA transfers that word to the next location in ADSP-

21mod870-110 memory.

The executable image contains code and data that must be

loaded into program and data memory. Program memory on

the ADSP-21mod870-110 is 24 bits wide, therefore two trans-

fers are used to load each word of program memory.

The host begins the download by asserting the RESET pin of

the ADSP-21mod870-110. The host then transfers all code and

data. All internal memory can be loaded in 5 ms.

Control Interface

The ADSP-21mod870-110 is controlled through two FIFOs in

DSP memory. The host sends a control event by writing to the

host-to-modem FIFO. The ADSP-21mod870-110 posts events

to the host by writing into the modem-to-host FIFO.

Data Interface

All data transferred to and from the ADSP-21mod870-110

passes through word FIFOs located in internal memory on the

ADSP-21mod870. The FIFOs are accessed through a control

structure that contains a pointer to the start of the FIFO in

memory, the length of the FIFO in 16-bit words, a pointer to

the next address to be read, and a pointer to the next address to

be written. The transmit and receive FIFOs are 1024 bytes

deep. Example code providing primitives for accessing the

byte-FIFOs is available from Analog Devices. Table I shows an

example of a data FIFO.

Table I. FIFO Example

ADSP-21mod870-110

Modem Statistics

Several modem statistics can be gathered through the IDMA

port. These statistics include call status, modulation in use,

connect rate, transmit and receive data rate, symbol rate, retrain

count, rate renegotiation count and others. Table II and Table

IV contain a complete listing of available modem statistics.

Modem Configuration

The modem is configured by programming various parameters

through the IDMA port. Table III and Table V contain com-

plete lists of modem configuration parameters.

Table II. Shell Status

Reference #

SS. 0

SS. 1

SS. 2

SS. 3

Function

Product Number

Application Version

Application Type

Programmable Flag Data

Table III. Shell Parameters

Reference #

SP. 0

SP. 1

SP. 2

SP. 3

SP. 4

SP. 5

Function

Serial Port Tx Time Slot

Serial Port Rx Time Slot

Serial Port Configuration

Programmable Flag Control

Programmable Flag Data

Host Interrupt Count

BASE

RD_ptr

WR_ptr

BASE + SIZE

INFO

INFO

INFO

INFO

REV. 0

–3–

Share Link: