Siemens M7-400, S7-400 12.1 Overview

M7-400 Expansions
12-2 S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
12.1 Overview
Introduction
You can expand your automation computer from the M7-400 range by adding
expansion modules for interface submodules, short AT modules, and/or the mass
storage module. The interface submodules can include the IF 962-COM,
IF 962-LPT, ... .
The following expansion modules are available:
•EXM 478 expansion module for up to 3 interface submodules
•ATM 478 AT adapter module for one short AT module
•MSM 478 mass storage module with hard disk and floppy disk drive and an
LPT1 printer port.
Expansion Socket
On the right-hand side of a CPU or an M7-400 application module there is a
120-pin socket (AT-ISA bus) for connecting expansions. There is a matching
connector for this socket on the left-hand side of the EXM 478, ATM 478, and MSM
478 expansion modules (Figure 12-1).
The EXM 478, ATM 478 and MSM 478 expansion modules have one expansion
socket each on the right-hand side so that further expansion modules can be
plugged in.