Smb8-Smb19: I/O Module Id And Errors - Siemens SIMATIC S7 System Manual

D.9

SMB8-SMB19: I/O module ID and errors

SMB8 through SMB19 are organized in byte pairs for expansion modules 0 to 5.
The even-numbered byte of each pair is the module-identification register. These bytes
identify the module type, the I/O type, and the number of inputs and outputs.
The odd-numbered byte of each pair is the module error register. These bytes provide an
indication of any errors detected in the I/O for that module.
See also SMW100-SMW114 System alarm codes (Page 822)
S7-200 SMART
System Manual, V2.3, 07/2017, A5E03822230-AF
Special memory (SM) and system symbol names
D.9 SMB8-SMB19: I/O module ID and errors
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