Data Exchange with the SM 335
3-37
SM 335 – High-Speed Analog Input/Output Module for the SIMATIC S7-300
6ES7 335-7HG00-8BA1
3.4.7
Channel-specific diagnostic bytes (bytes 4-15)
Channel type (byte 4)
The SM 335 flags the type of channel in which the error occurred in byte 4 of the
diagnostic data (00
H
: general error; 71
H
input; 73
H
output).
Channel vector (byte 7)
In byte 7 of the diagnostic data, the SM 335 flags the input or output on which a
channel-specific error has been detected.
7
6
5
4
3
2
1
0
Channel input CH0
Channel input CH1
Channel input CH2
Channel input CH3
Channel output CH3
Channel output CH2
Channel output CH1
Channel output CH0
Fig. 3-14
Modification indicator bits for channel-specific diagnostic bytes
Analog input (bytes 8-11)
The SM 335 sets bits in the channel-specific diagnostic bytes for inputs when an
error/fault is detected at one of the inputs. The channel-specific diagnostic bytes
for inputs have the following format:
7
6
5
4
3
2
1
0
Parameter assignment error
Common-mode error
Open wire
Overflow
Underflow
Fig. 3-15
Channel-specific diagnostic byte for an analog input
Parameter assignment error (bytes 8-11, bit 0)
A parameter assignment error has occurred if the bit is set.
