C.11 Communication Errors
C.11 Communication Errors
♦ MEMOBUS/Modbus Error Codes
A list o f MEMOBUS/Modbus errors appears below.
When an error occurs, remove whatever caused the error and restart communications.
Error Code
Error Name
Cause
01H
Function Code Error
• Attempted to set a function code from a PLC other than 03H, 08H, and 10H.
02H
R egister Number Error
• A register number specified in the command m essage does not exist.
• Attempted to send a broadcast m essage using other register numbers than 0001H or 0002H.
03H
B it Count Error
• Read data or write data is greater than 16 bits. Invalid command m essage quantity.
• In a write m essage, the “Number o f Data Items” contained within the m essage does not equal tw ice the amount o f data words (i.e., the total o f Data 1+ Data
2, etc.).
21H
Data Setting Error
• Control data or parameter write data is outside the allowable setting range.
• Attempted to write a contradictory parameter setting.
22H
Write M ode Error
• During run, the user attempted to write a parameter that cannot be written to during run.
• During an EEPROM mem ory data error (CPF06), the master attempted to write to a parameter other than A 1-00 to A 1-05, E1-03, or o2-04.
• Attempted to write to read-only data.
23H
DC Bus Undervoltage Write Error
• During an undervoltage situation, the master attempted to write to parameters that cannot be written to during undervoltage.
24H
Write Error During Parameter Process
• Master attempted writing to the drive w hile the drive was processing parameter data.
• Slave Not Responding
In the following situations, the slave drive will ignore the command message sent from the master, and not send a
response message:
• When a communications error (overrun, framing, parity, or CRC-16) is detected in the command message.
• When the slave address in the command message and the slave address in the drive do not match (remember to set the
slave address for the drive using H5-01).
• When the gap between two blocks (8-bit) o f a message exceeds 24 bits.
• When the command message data length is invalid.
N o te: I f the slave address specified in the comm and message is 00H, all slaves execute the w rite function, but do not return response
m essages to the master.
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YASKAWA ELECTRIC SIEP C710616 33D YASKAWA AC Drive L1000A Technical Manual