Technical data

Table Of Contents
SFCs for H CPUs
System Software for S7-300/400 System and Standard Functions - Volume 2/2
29-4
A5E00739858-01
Example of Using SFC 90
With SFC 90 "H_CTRL," you can make sure that no link-up and no updating is
started at times when the maximum resources of the CPU are required.
You can achieve this by including the following program sections on the master
CPU prior to the period of increased process activity:
Call SFC 90 with MODE = 3 and SUBMODE =0 (disable link-up)
Call SFC 90 with MODE = 1 and SUBMODE = 0 (disable updating)
At the end of the period of increased activity, include the following program
sections on the master CPU:
Call SFC 90 with MODE = 4 and SUBMODE = 0 (re-enable link-up)
Call SFC 90 with MODE = 2 and SUBMODE = 0 (re-enable updating).