GE IC698CPE030 RX7i VME M Class 600Mhz CPU with Embedded 10/100 Ethernet
The LEDs on the front of the Bus Controller indicate its operating status. The top twoLEDs should be on during normal operation. The bottom LED is not used.
Shows the status of the Bus Controller. This LED blinks during power up diagnostics.
Shows the status of the bus. This LED is on steadily when the bus is
operating properly. It blinks for intermittent bus errors and is off for a
failed bus. It is also off when no configuration has been received from
the PLC CPU.
Hand–held Monitor Connector
The Hand–held Monitor connector on the Bus Controller faceplate provides attachment
for a Hand–held Monitor. For Bus Controller IC697BEM931, the lower HHM connector,
if present, is not used. All Hand–held Monitor functions except I/O block Device Num ber assignment
can be performed with the HHM connected to the Bus Controller. Bus
and block operation can be monitored, circuits forced or unforced, outputs Pulse Tested,
diagnostic messages displayed, and faults cleared, from this convenient central location.
Hand–held Monitor version IC660HHM501C (or later), permitting selection of a “host
CPU” is recommended for proper operation with the Series 90–70 PLC.
Terminal Assembly
Serial bus and shield wiring connections are made to the removable terminal strip on the
front of the Bus Controller. For Bus Controller IC697BEM931, only the upper three ter minals are used.
To remove the Terminal Assembly without disturbing the continuity of
the bus, jumpers are used. See chapter 2.

The Genius bus is a shielded twisted–pair wire, daisy–chained between devices, and
terminated at both ends. Proper cable selection is critical to successful operation of the
system. Suitable cable types are listed in the Genius I/O System User’s Manual.
Conservative wiring practices, as well as national and local codes, require physical sepa ration
between control circuits and power distribution or motor power. Refer to sections
430 and 725 of the National Electric Code.
Bus Type Daisy–chained bus cable; single twisted pair plus shield or Twinax.
Fiber optics cable and modems can also be used.
Bus Termination 75, 100, 120, or 150 ohm resistor at both ends of electrical bus cable.
Baud Rate Configurable. 153.6 Kbaud standard, 153.6 Kbaud extended, 76.8
Kbaud, or 38.4 Kbaud.
Maximum Bus Length 7500 feet at 38.4 Kbaud, 4500 feet at 76.8 Kbaud, 3500 feet at 153.6
Kbaud extended, 2000 feet at 153.6 Kbaud, standard. Maximum
length at each baud rate also depends on cable type. Chapter 2 pro vides a complete list of cable types, showing corresponding bus
lengths and baud rates.
Greater bus lengths are possible using sections of fiber optics cable
with modems.
Maximum Number of
Devices
32 devices at 153.6 Kbaud standard, 153.6 Kbaud extended, or 76.8
Kbaud. 16 devices at 38.4 Kbaud. Includes bus controller and typi cally a Hand–held Monitor.
Data Encoding Each bit is encoded into three dipulses, majority voted at the receiver
to correct any single dipulse errors. A dipulse is an AC code consist ing of a positive then negative excursion of voltage. Dipulses are
individually sampled to reject low and high frequency interference.
Modulation Technique Frequency Shift Keying (FSK) 0 to 460.8 KHz max. (153.6 Kilobaud)
Isolation 2000 volts Hi–Pot, 1500 volts transient common mode rejection.
Signal/noise Ratio 60 db