
MODBUS Communication
– Failures and warnings DO
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TI 12J06J01-00EN-P
3. Failures and Warnings DO
Device failures and Measurement warnings are checked and identified by bit content (0 or 1) in
specific Hold Registers (HR2093 and HR2094). The definition of each bit, the root cause and
possible remedy are explained in table 3.1.
Table 3.1: Bit assignment for DO71/DO72 failures/warnings
Bit#
Bit definition
Root cause & Remedy
0:
0x00000000 Reference channel overflow
Reference amplitude too high.
Decrease reference current.
1:
0x00000002 Temperature too high
The temperature is too high for
performing a measurement.
2:
0x00000004 Reference photo detector overflow A
Reference amplitude is too
low/high;
Sensor cap is not attached;
Too much ambient light.
Adjust reference current;
Attach sensor cap;
Reduce ambient light.
3:
0x00000008 Signal channel overflow
Signal amplitude too high.
Decrease signal current.
4:
0x00000010 Reserved
5:
0x00000020 Reserved
6:
0x00000040 No sensor calculation /
Amplitude too low
Signal amplitude is too low;
Sensor cap is not attached.
Decrease signal current;
Attach sensor cap.
7:
0x00000080 Pulse counter overflow
Pulse counter reached its
maximum value.
8:
0x00000100 Reference amplitude out of range
Reference amplitude is too
low/high;
Sensor cap is not attached.
Adjust reference current;
Attach sensor cap.
9:
0x00000200 Signal photo detector overflow
Signal amplitude is too high;
Sensor cap is not attached;
Too much ambient light.
Adjust signal current;
Attach sensor cap;
Reduce ambient light.
10:
0x00000400 Reference photo detector overflow B
Reference amplitude is too
low/high;
Sensor cap is not attached;
Too much ambient light.
Adjust reference current;
Attach sensor cap;
Reduce ambient light.
11:
0x00000800 Memory Write error detected
Memory errors occurred.
Contact the relevant
YOKOGAWA sales office.
12:
0x00001000 PME timeout
Internal error.
Contact the relevant
YOKOGAWA sales office.