IC697CPU772 GE Series 90-70 12MHz Floating Point CPU Processor

GE IC697CPU772 Series 90-70 Floating Point CPU Module

The GE IC697CPU772 serves as the primary IC697CPU772 Floating Point CPU Module utilized to execute high-speed arithmetic processing and real-time control algorithms across Series 90-70 platforms. Driven by an 80C186 microprocessor operating at a 12 MHz system clock speed, the module executes floating-point mathematical routines while occupying a single slot in the main PLC backplane rack. The unit manages onboard memory expansion capabilities up to 512 KB, retains system program data using a dedicated backup battery, and communicates with programming software tools through an integrated serial interface port.

Hardware Specifications

Backplane Bus Communication Velocity & Firmware Integrity

The IC697CPU772 processor controls high-speed VME-based backplane bus transactions, while the internal logic bus coordinator maintains deterministic sweep execution times. Consequently, the CPU updates discrete and analog field I/O values without incurring computational delays during floating-point matrix calculations. Furthermore, onboard flash and CMOS registers enforce firmware flash compatibility, whereas hardware diagnostic routines validate system configuration checksums during cold boot power-up sequences to block corrupted code execution.

Frequently Asked Questions

Q: How do field technicians preserve memory contents during a system power shutdown?

A: An onboard replaceable lithium battery maintains power to the CMOS RAM chip, preventing program loss when external backplane power drops below operating thresholds.

Q: What programming environments support hardware configuration and logic download for this CPU?

A: Engineers configure parameters and write ladder logic programs using MS-DOS or Microsoft Windows-based programming packages via the CPU serial programming port.

Q: Does installing additional memory expansion boards increase the 5 VDC backplane current drain beyond 1.2 A?

A: No, the 1.2 A backplane power rating at 5 VDC already accounts for the maximum power draw of attached memory expansion boards.

Field Installation Guidelines

1. Turn off main power to the Series 90-70 rack prior to inserting or extracting the CPU module from Slot 1.
2. Connect the lithium backup battery cable to its designated connector on the CPU board before sliding the module into the rack chassis.
3. Align the circuit board edges with the top and bottom card guides, pushing the unit steadily until the rear edge connector seats fully into the backplane.
4. Fasten the top and bottom module retaining screws to secure the unit against environmental vibration.
5. Plug the serial programming cable into the front serial port to download system configuration files and CPU firmware settings.