Siemens S5-100U - Calculating Interrupt Reaction Times

S5-100U Interrupt Processing
10.2 Calculating Interrupt Reaction Times
The total reaction time is is the sum of the following times:
• Signal delay of the module triggering the interrupt (= time from the input signal change
triggering the interrupt to the activation of the interrupt line)
• Interrupt reaction time of the CPU
• Execution time of the interrupt program (= sum of all STEP 5 statements in the interrupt
evaluation program)
Calculate the interrupt reaction times as follows:
CPU’s interrupt reaction time = basic reaction time + additional reaction times
The basic reaction time is 0.6 ms and is valid if the following conditions exist:
• No integrated FBs were used.
• No parameters for the integral clock are set.
• No programmer/OP functions are present.
• OB13 has not been programmed.
• No SINEC L1 is connected.
The additional reaction times are variable. They are listed in Table 10-1.
Table 10-1. Additional Reaction Times
Interrupt Reaction
Times
Additional Running Functions of the
Programmable Controller
Integrated FBs
Parameters set for clock
OP functions
Programmer functions:
Status block/Transfer block
Output address
Compress
• If no blocks are moved
• If blocks are moved
SINEC L1 bus to the programmer interface
0.5 ms
0.2 ms
Depending on the number of bytes used
for loading the memory
0.5 ms
18 ms per kbyte
• Depending on the number of blocks
present (after overall reset 31 ms)
• 600 ms per each 1kword of
instructions in the block to be
moved
8.0 ms
EWA 4NEB 812 6120-02 10-5