Siemens SIMATIC S7-300 Reference Manual page 472

Data record 1 structure
The figure below shows the structure of data record 1 for the parameters of the
digital input modules.
You activate a parameter by setting the corresponding bit to "1".
Figure A-1
A-4
7 6
Byte 0
Diagnostics interrupt enable
Hardware interrupt enable
7 6 5 4 3 2 1
Byte 1
on falling edge at channel group 1
on rising edge at channel group 2
on falling edge at channel group 2
on rising edge at channel group 3
on falling edge at channel group 3
7 6 5 4 3 2 1
Byte 2
on falling edge at channel group 5
on rising edge at channel group 6
on falling edge at channel group 6
on rising edge at channel group 7
on falling edge at channel group 7
Byte 3
Data Record 1 for Parameters of the Digital Input Modules
0
0
Hardware interrupt
on rising edge at channel group 0
on falling edge at channel group 0
on rising edge at channel group 1
0
Hardware interrupt
on rising edge at channel group 4
on falling edge at channel group 4
on rising edge at channel group 5
Not relevant
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03