Response Frame Structure - Omron KP**G-OD Series Communications Manual

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Response Frame Structure

Normal Response Frames
Slave Function
address code
1 1
CRC-16 calculation range
Error Response Frames
Slave Function Error
address code
code
1 1
CRC-16 calculation range
Slave address
Function code
Error code
CRC-16
No Response
In the following cases, the received command is not processed and a response is not returned. A timeout will
occur at the host device.
• The slave address in the received command is different from the communications unit number set in the KP
inverter.
• A parity error, framing error, or overrun error occurred due to a transfer error or other error.
• A CRC-16 code error occurred in the received command frame.
• A time interval greater that 3.5 characters occurred between data while receiving a command frame. In the
following case, the command is processed, but a response is not returned.
• Broadcast transmission (Slave address: 00hex)
Grid Connect Photovoltaic Inverter KPG/KPL Communication Manual
Data
CRC-16
1 2
The nodenumber that was specified in the command frame
is returned here. This is the node number of the
responding KP inverter.
The function code that was received is returned here.
In an error response frame, 80 hex is added to the value to
indicate that this is an error response.
Example: Received function code = 03 hex
Function code in error response frame = 83 hex
An end code that indicates the error.
Cyclical Redundancy Check
These two bytes are a check code calculated from the
slave address through the end of the data in hexadecimal.
CRC-16
2
4 MODBUS
4
4-5