GE 90-30/20/Micro manual Svcreq #12 Read PLC Run State

4

SVCREQ #12: Read PLC Run State

Use SVCREQ function #12 to read the current RUN state of the PLC CPU.

Note

Of the CPUs discussed in this manual, Service Request 12 is supported only by 90-30 CPUs, beginning with Release 8.0.

The parameter block is an output parameter block only; it has a length of one word.

1 = run/disabled

2 = run/enabled

address

Example:

In the following example, the PLC run state is always read into location %R4002. If the state is Run/Disabled, the CALL function calls program block DISPLAY.

		_____		_____
%I0102
—— ———		SVC_——————————		EQ_ —
		REQ		WORD		__________
CONST —FNC			CONST —I1		Q———————— DISPLAY		—
0012			0001			__________
%R4002—PARM			%R4002—I2
	_____		_____

GFK-0467K Chapter 4 Series 90-30/20/Micro Instructions Set 4-153