GE 90-30/20/Micro manual Parameters, End

4

The function passes power to the right whenever power is received, unless:

∙Not all references of the type specified are present within the selected range.

∙The CPU is not able to properly handle the temporary list of I/O created by the function.

∙The range specified includes I/O modules that are associated with a “Loss of I/O” fault.

_____

(enable)(ok)

(starting address) —ST

(ending address) -END

—ALT

_____

Parameters:

Parameter

Description

enable	When the function is enabled, a limited input or output scan is performed.
ST	ST is the starting address or set of input or output points or words to be serviced.
END	END is the ending address or set of input or output points or words to be serviced.
ALT	For the input scan, ALT specifies the address to store scanned input point/word values.
	For the output scan, ALT specifies the address to get output point/word values from to
	send to the I/O modules. For Model 331 and later CPUs, the ALT parameter can have
	an effect on speed of DOIO function block execution (see Note below and the section on
	the enhanced DO I/O function for 331 and later CPUs on page 4-110).
ok	The ok output is energized when the input or output scan completes normally.

Note

For Model 331 and later CPUs, the ALT parameter of the DOIO function block can be used to enter the slot of a single module in the main rack. When that is done, the DOIO function block will execute in 80 microseconds instead of the 236 microseconds required when the block is programmed without the ALT parameter. No error checking is performed to prevent overlapping reference addresses or module type mismatches.

Valid Memory Types:

Parameter

flow

%I

%Q

%M

%T

%S

%G

%R

%AI

%AQ

const

none

enable

•

ST

•

•

•

•

END

•

•

•

•

ALT

•

•

•

•

•

•

•

•

•

ok

•

•

•Valid reference or place where power may flow through the function.

4-110 Series 90-30/20/Micro Programmable Controllers Reference Manual–September 1998 GFK-0467K