Siemens ET 200pro Operating Instructions Manual page 503

Note
Grouping electronic modules in the configuration
You can group two identical digital electronic modules of type 4 DI / 4 DO DC 24V/0.5A
within a byte in the input and output range of the process image.
You can find more information on this topic in the chapter Grouping electronic modules in the
configuration (Page 142).
Address space for 4 DIO / 4 DO DC 24V/0.5A
Figure A-26
Note
Input/output bits 0 to 3
Read or write access is always possible to the input/output bit, regardless of the parameter
settings.
If a channel is configured as output, the value at the input bit is "0". If a channel is configured
as input, and an output bit is written to it, it has no effect.
ET 200pro distributed I/O system
Operating Instructions, 03/2013, A5E00335544-08
Address space 4 DIO / 4 DO DC 24V/0.5A
Appendix
A.3 IO address space
503