Oriental motor BLH Series - Page 73

73
Modbus RTU control (RS-485 communication)
z
Example of exception response
Slave address 01h Query Slave address 01h
Function code 10h Function code 90h
Data
Register address (upper) 04h Data Exception code 04h
Register address (lower) 80h Error check (lower) 4Dh
Number of registers (upper) 00h Response Error check (upper) C3h
Number of registers (lower) 04h
Number of data bytes 08h
Value write to register address (upper) FFh
Value write to register address (lower) FFh
Value write to register address +1 (upper) FFh
Value write to register address +1 (lower) FFh
Error check (lower) C8h
Error check (upper) 9Bh
z
Exception code
This code indicates why the process cannot be executed.
Exception code Communication error code Cause Description
01h 88h Invalid function
The process could not be executed because the function code
was invalid.
•
The function code is not supported.
•
The sub-function code for diagnosis (08h) is other than 00h.
02h 88h Invalid data address
The process could not be executed because the data address
was invalid.
•
The register address is not supported (other than 0000h to
57FFh).
•
The register address and the number of registers are 5800h or
more in total.
03h 8Ch Invalid data
The process could not be executed because the data was invalid.
•
The number of registers is 0.
•
The number of bytes is other than "the number of register ×2."
•
The data length exceeds the maximum value.
04h
89h
8Ah
8Ch
8Dh
Slave error
The process could not be executed because an error occurred at
the slave.
•
Communication with user I/F is in progress (89h).
Execute the following with the
MEXE02
- Download (under writing to the driver)
- Initialization or Conguration
- I/O test or teaching function is being performed
•
NV memory processing in progress (8Ah)
- Internal processing is in progress (S-BSY is ON).
- An alarm of the EEPROM error is present
•
Outside the parameter setting range (8Ch)
- The value write is outside the setting range.
•
Command execute disable (8Dh)
z
About slave error
When the "Slave error response mode" parameter is set to "0: Normal response is returned," even if the slave error occurs,
a normal response is returned. Set it when no exception response is required, as in the case of a touch screen.