Oriental motor BLH Series - Detection of Communication Errors

95
Modbus RTU control (RS-485 communication)
11.11 Detection of communication errors
The functions to detect that an error occurs in RS-485 communication are three types including communication errors,
alarms, and information.
11.11.1 Communication errors
The communication error can be checked using the "Communication error history" command via RS-485
communication or the
MEXE02
. (Ten data in order of the latest)
If the error code 84h of the communication error is generated, the C-DAT/C-ERR LED will be lit in red.
When communication errors other than 84h is generated, the LED will not be lit or blink.
The communication error history is saved in the RAM. It is cleared when the power supply of the driver is turned OFF.
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Communication errors
Communication errors Error code Cause
RS-485 communication error 84h
A transmission error was detected. Refer to "Causes and descriptions of transmission
errors" for details.
Command not yet dened 88h
The function code was invalid (exception code 01h)
· The function code is not supported.
· The sub-function code for diagnosis (08h) is other than 00h.
The data address was invalid (exception code 02h)
· 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.
User I/F communication in progress 89h Download or initialization is being executed with the
MEXE02
(exception code 04h)
*
Non-volatile memory processing in
progress
8Ah
Non-volatile memory processing is in progress (exception code 04h)
*
· Internal processing is in progress. (SYS-BSY is ON.)
· An EEPROM error alarm is present.
Outside setting range 8Ch
The data was invalid (exception code 03h)
· The number of registers is 0.
· The number of bytes is other than twice the number of registers.
· The data length is outside the specied range.
The value write was out of the setting range (exception code 04h)
*
Command execute disable 8Dh The command could not be executed (exception code 04h)
*
*
It is the 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.
11.11.2 Causes and descriptions of transmission errors
The slave discards the query and does not return a response if any of the following transmission errors is detected.
Transmission error Description
Framing error Stop bit 0 was detected.
Parity error A mismatch with the specied parity was detected.
Mismatched CRC The calculated value of CRC-16 was found not matching the error check value.
Invalid message length The message length exceeded 256 bytes.