73m2901cl TDK Corp., 73m2901cl Datasheet - Page 9

• Manufacturer Part Number: 73m2901cl
• Description: V.22 Single Chip Modem
• Manufacturer: TDK Corp.

FIRMWARE DESCRIPTION*
An “AT” command interpreter provides command
and configuration of the 73M2901CL. This provides
the user a uniform interface to control the modem in
embedded applications.
The signal processing is performed to provide data
to the DAC and process data from the A/D
converter. A MAC hardware coprocessor is provided
for computation.
To provide maximum flexibility, the system host
processor can access the internal RAM and Control
Register space in the modem. This will allow the
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.
* Refer to the TDK 73M2901CL User Guide for a complete description of the software.
9
FIRMWARE FEATURES
“AT” command set
Supports data standards through V.22bis
Provides DAA control firmware (e.g. ring detect,
hook control)
Multinational Call progress support (FCC68,
CTR21, JATE, etc.)
Caller ID capability
On hook Line-In-Use detection support (No line
seizure will occur when a Line-In-Use condition
is detected)
Off hook Parallel Pick-Up detection support
(Line seizure will be aborted as soon as a
Parallel Pick-Up condition is detected)
Directly interfaces with standard V.24/EIA-232
bus drivers (3.3V inverted level) serial interface
using the built in serial port and firmware control
of port pins
Provides
including four imprecise and four precise call
progress
frequency and detection threshold
Blacklisting capability
Long Space disconnect
Inactivity timeout
Host access to program RAM provided
User programmable general purpose I/O
V.22bis Single Chip Modem
o
o
o
o
o
o
detect
tone
FSK demodulation (V23 or Bell202)
DTMF demodulation
Intra 1st/2nd ring CID data operation
Post
operation
Tip/Ring voltage sensing
Quiescent line validation
generation
Line
filters
reversal
with
73M2901CL
and
programmable
CID
detection
data