GE manual GFK-0467K Series 90-30/20/Micro Instructions Set 139

4

SVCREQ #3: Change Programmer Communications Window Mode and Timer Value

Use SVCREQ function #3 to change the programmer communications window mode and timer value. The change will occur in the CPU sweep following the sweep in which the function is called.

Note

Of the CPUs discussed in this manual, Service Request 3 is supported only by 90-30 CPUs, beginning with Release 8.0.

The SVCREQ function #3 will pass power flow to the right unless a mode other than 0 (Limited), 1 (Constant), or 2 (Run-to-Completion) is selected.

The parameter block has a length of one word.

To disable the programmer window, enter SVCREQ function #3 with this parameter block:

High Byte	Low Byte
0	0

address

To enable the programmer window, enter SVCREQ function #3 with this parameter block:

High Byte	Low Byte
Mode	Value from 1 to 255 ms

address

GFK-0467K Chapter 4 Series 90-30/20/Micro Instructions Set 4-139