Siemens Simatic M7-400 Reference Manual page 580

Diagnostic Data of the Signal Modules
Bytes 2 and 3 of the SM 421; DI 16
Byte 2
Byte 3
Figure B-5
Bytes 4 to 8 of the SM 421; DI 16
Byte 4
Byte 5
Byte 6
Byte 7
Byte 8
Figure B-6
B-6
24/60 VUC
7 6 5 4 3 2 1 0
0 0 0 0
0 0 0
Operating status 0: RUN
7 6 5 4 3 2 1 0
0 0 0 0 0 0
EPROM error
Hardware interrupt lost
Bytes 2 and 3 of the Diagnostic Data of the SM 421; DI 16 x 24/60 VUC
24/60 VUC
7 6 5 4 3 2 1 0
0
Channel type B#16#70: digital input
7 0
7 0
7 6 5 4 3 2 1 0
Channel error, channel 0
Channel error, channel 1
...
Channel error, channel 6
Channel error, channel 7
7 6 5 4 3 2 1 0
Channel error, channel 8
... Channel error, channel 9
Channel error, channel 14
Channel error, channel 15
Bytes 4 to 8 of the Diagnostic Data of the SM 421; DI 16 x 24/60 VUC
S7-400, M7-400 Programmable Controllers Module Specifications
1: STOP
Number of diagnostics bits that the module
outputs per channel: 8 bits long
Number of channels of the same
type in one module: 16 channels
A5E00069467-07