GE 90-30/20/Micro manual Differences Between MCRs and JUMPs

4

Both forms of the MCR function have the same parameters. They both have an enable boolean input EN and also a name which identifies the MCR. This name is used again with an ENDMCR instruction. Neither the MCR nor the MCRN function has any outputs; there can be nothing after an MCR in a rung.

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[ MCR ] or -[ MCRN]

Differences Between MCRs and JUMPs

With an MCR function, function blocks within the scope of the MCR are executed without power flow, and coils are turned off. In the following example, when %I0002 is ON, the MCR is enabled. When the MCR is enabled—even if %I0001 is ON—the ADD function block is executed without power flow (i.e., it does not add 1 to %R0001), and %Q0001 is turned OFF.

%I0002	FIRST
—— ———[ MCR ]
	_____
%I0001			%Q0001
—— ———————— ADD		—————————————————————————————————————————————————( )-
	INT
	%R0001-I1	Q— %R0001
	1—I2
	_____

+[ ENDMCR ]

With a JUMP function, any function blocks between the JUMP and the LABEL are not executed, and coils are not affected. In the following example, when %I0002 is ON, the JUMP is taken. Since the logic between the JUMP and the LABEL is skipped, %Q0001 is unaffected (i.e., if it was ON, it remains ON; if it was OFF, it remains OFF).

%I0001

—— —————————————————————————————————————————————————————————————————>>TEST1

	_____
%I0001			%Q0001
—— ———————— ADD		—————————————————————————————————————————————————( )-
	INT
	%R0001-I1 Q- %R0001
	1-I2
	_____

––TEST1 :

GFK-0467K Chapter 4 Series 90-30/20/Micro Instructions Set 4-125