TDK 73M2901/5V FIRMWARE DESCRIPTION2

73M2901/5V

Advanced Single

Chip Modem

FIRMWARE DESCRIPTION2

An “AT” command interpreter provides command

and configuration of the 73M2901/5V. This provides

the user a uniform interface to control the modem in

embedded applications.

The signal processing is performed by obtaining

data from and providing data to the integrated A/D

converter. A MAC hardware processor is provided

for computation.

To provide maximum flexibility, the system host

processor can access the internal RAM and Control

OEM user to modify parameters such as filter

response, transmit levels through the AT command

set using proprietary commands. The host

processor can also access the modem I/O port pins,

providing extended I/O capability.

FIRMWARE REQUIREMENTS

The modem always powers up in the idle (on hook)

mode. “AT” commands are issued via the serial

interface from the host. All modem configuration

commands are received in this manner. The data

modem firmware is contained in an internal ROM.

The firmware will automatically enter a power saving

idle mode if the modem is on hook and there are no

incoming host commands. The modem

automatically powers up upon receiving the next

command. This power up sequence occurs without

delay to the host. This function, while saving power,

is transparent to the host processor and can be

disabled by the host via an “AT” command. The

host can also program the modem to power down

via external pin (DTR) or via a firmware command.

2 For a detailed description of the firmware consult the TDK

73M2901 User’s Manual.

FIRMWARE FEATURES

· “AT” command set

· Supports data standards through V.22bis

· Provides DAA control firmware (e.g. ring detect,

hook control, line in use detection support)

· Multinational Call progress support (FCC68,

CTR21, JATE…)

· Caller ID capability

FSK demodulation (V23 or Bell202)

Intra 1st/2nd ring CID data operations

Post Line reversal CID data operations

· Interfaces with standard V.24/EIA-232 (3-5 volt

inverted level) serial interface using the built in

serial port and firmware control of port pins

· Provides tone generation and detection, four

imprecise and four precise call progress detect

filters

· Host access to program RAM provided

· User access to modem functions