Parallel Pin Configurations - Multitech SocketModem MT5600SMI-32 Developer's Manual

Parallel Pin Configurations

The parallel interface SocketModem uses a 22-pin interface to provide an on-board DAA with tip and ring
connections, audio circuit for call-progress monitoring, and parallel interface.
Pin Descriptions for a Parallel SocketModem Device
Pin # Signal Name
1 Tip
2 Ring
24 –RESET
25 A1
26 DGND
27 D7
29 D2
30 INT
31 A0
Multi-Tech Systems, Inc. SocketModem MT5600SMI Developer's Guide
Figure 2–3. Parallel SocketModem Pins
I/O Description
I/O Telephone Line Interface – TIP
I/O Telephone Line Interface – RING
I Modem Reset (CMOS input with weak pull-up). The active low –RESET input
resets the SocketModem logic and returns the AT command set to the original
factory default values or to "stored values" in NVRAM.
The modem is ready to accept commands within 6.5 seconds of power-on or
reset. Reset must be asserted for a minimum of 300 ns.
Host Bus Address Line 1
GND
Digital Ground
O
Host Bus Data Line 7
O
Host Bus Data Line 2
O
Host Bus Interrupt Line, Active High, Resets on Low
I
Host Bus Address Line 0
Chapter 2 – Mechanical Specifications
11