Month: August 2025

Flash Memory

This module uses flash memory for storage of the

operating system firmware (this module does not sup

port storage of user program in the flash memory).  This

allows updates of the firmware without disassem

bling the module or replacing EPROMs.  The oper

ating system firmware is updated by connecting a

PC compatible computer to the module’s serial port

and running the Loader software included with the

firmware floppy disk.

User Memory

Program and data memory for the CPM 790 is provided

by a memory board with 1 Mbyte of battery-backed

CMOS RAM.  512 Kbytes of this memory is available for the

user’s application program and data.  This memory board is

an integral part of the CPM 790 module and is included

with the module.

User Memory

Program and data memory for the CPM 790 is provided

by a memory board with 1 Mbyte of battery-backed

CMOS RAM.  512 Kbytes of this memory is available for the

user’s application program and data.  This memory board is

an integral part of the CPM 790 module and is included

with the module.

Flash Memory

This module uses flash memory for storage of the

operating system firmware (this module does not sup

port storage of user program in the flash memory).  This

allows updates of the firmware without disassem

bling the module or replacing EPROMs.  The oper

ating system firmware is updated by connecting a

PC compatible computer to the module’s serial port

and running the Loader software included with the

firmware floppy disk.

Functions

The CPM 790 is a single slot programmable controller

CPU which allows floating point calculations.  The CPM

790 is programmed and configured with MS-DOS or

Windows based programming software for use in

Emergency Shut-Down (ESD), fire and gas, and other

critical control applications.  It communicates with I/O

and smart option modules over the rack mounted

backplane (IC697CHS750. 782. 783. 790. 791) by way of

the VME C.1 Standard format.

The CPM 790 must be used in conjunction with a

Standalone C program which provides Triple Modular

Redundancy (TMR) operating and autotest routines.  It

will not operate unless this program is included in the

loaded application program.

For detailed information on TMR systems, see

Reference 4. the IC66* Modular Redundancy Flexible

Triple Modular Redundant (TMR) System User’s Manual.

Supported option modules include IC697 LAN Interface

modules, Programmable Coprocessor, Alphanumeric

Display Coprocessor,  Bus Controller for IC660/661 I/O

products, Communications modules, I/O Link Interface,

and all of the IC697 family of discrete and analog I/O

modules.

Features

•Single slot CPU

•Provides 1 Mbyte of battery-backed memory in the

same slot (up to 512 Kbytes available for use by

ladder diagram application program)

•Supports floating point calculations

•Up to 12K discrete inputs and outputs (any mix

simplex mode only); 2048 voted discrete inputs, 2048

voted discrete outputs

•Up to 8K analog inputs (simplex mode only) and

8K analog outputs (simplex mode only); 1024 voted

analog inputs

•0.4 microseconds per boolean function

•64 MHz, 80486DX2 microprocessor

•Supports IC660/IC661 I/O (and IC697 I/O in sim

plex mode only)

•Programmed by MS-DOS , or Windows software

products running on Windows 95 or Windows

NT over Ethernet TCP/IP or through the SNP port.

•Configurable data and program memory

•Battery-backed calendar clock

•Three position operation mode switch

•Password controlled access

•Remote programmer keyswitch memory protection

•Four status LEDs

•Software configuration (No DIP switches

or jumpers)

•Reference information inside front door

•In-system upgradable firmware

Batteries

A lithium battery (IC697ACC701) is installed as shown

in Figure 2.  This battery maintains program and data

memory when power is removed and operates the

calendar clock.  Be sure to install the new battery be

fore removing the old battery.  If during power-up

diagnostics a low battery is detected the Module OK

LED (top) will not stay on.  Specific indication of a low

battery state is detailed in Reference 2.

Removing a Module

The following instructions should be followed when

removing a module from its slot in a rack.

Grasp the board firmly at the top and bottom of

the board cover with your thumbs on the front of

the cover and your fingers on the plastic clips on

the back of the cover.

Squeeze the rack clips on the back of the cover

with your fingers to disengage the clip from the

rack rail and pull the board firmly to remove it

from the backplane connector.

Slide the board along the card guide and remove it

from the rack.

Configuration

The IC697 CPU and I/O system is configured with

MS-DOS or Windows based programming software.

There are no DIP switches or jumpers used to config

ure the system. The CPU verifies the actual module

and rack configuration at power-up and periodically

during operation. The actual configuration must be

the same as the programmed configuration.  Devi

ations are reported to the CPU alarm processor func

tion for configured fault response.  Consult Reference

1 for a description of configuration functions.

Batteries

A lithium battery (IC697ACC701) is installed as shown

in Figure 2.  This battery maintains program and data

memory when power is removed and operates the

calendar clock.  Be sure to install the new battery be

fore removing the old battery.  If during power-up

diagnostics a low battery is detected the Module OK

LED (top) will not stay on.  Specific indication of a low

battery state is detailed in Reference 2.

Programmer Connection, Ethernet TCP/IP

Connecting your programmer via an Ethernet

TCP/IP network requires installation of an Ethernet

Interface module in the PLC.  This can be either the

Ethernet Controller, IC697CMM741. or Ethernet

Interface (Type 2), IC697CMM742.  Before connecting

your programmer and PLC to the Ethernet TCP/IP

network you must set the IP address in the Ethernet

Interface.  After setting the IP address, connect the

PLC and the programmer running Windows software

to the Ethernet Interface.  For more detailed

information on the programmer connection via

Ethernet TCP/IP, refer to the TCP/IP Ethernet

Communications (Type 2) User’s Manual, and the

Windows programming manual, GFK-1295.

The CPU verifies the actual module

and rack configuration at power-up and periodically

during operation. The actual configuration must be

the same as the programmed configuration.  Devi

ations are reported to the CPU alarm processor func

tion for configured fault response.  Consult Reference

1 for a description of configuration functions.

Programmer Connection, Parallel

For a parallel interface (MS-DOS programmer only)

connect the programmer to the top port connector on

the Bus Transmitter Module (IC697BEM713) as shown

in Figure 1.  Consult  Reference 2 for a description of

programming functions.

Serial Port

The 15-pin D-connector provides the connection to an

RS-485 compatible serial port as shown in Figure 3.

This port provides a serial connection to a Standard

Serial COM port, or to a Work Station Interface board

installed in the programming computer.

Squeeze the rack clips on the back of the cover

with your fingers to disengage the clip from the

rack rail and pull the board firmly to remove it

from the backplane connector.

Slide the board along the card guide and remove it

from the rack.