Message Examples; Reading Drive Memobus/Modbus Register Contents; Loopback Test - YASKAWA U1000 Technical Manual

C.8 Message Examples
Below are some examples of command and response messages.
u

Reading Drive MEMOBUS/Modbus Register Contents

Using the function code 03H (Read), a maximum of 16 MEMOBUS/Modbus registers can be read out at a time.
The following table shows message examples when reading status signals, error details, data link status, and frequency
references from the slave 2 drive.
Command Message
Slave Address
Function Code
Upper
Starting No.
Lower
Upper
Data Quantity
Lower
Upper
CRC-16
Lower
u

Loopback Test

Function code 08H performs a loopback test that returns a response message with exactly the same content as the command
message. The response message can be used to check communications between the master and slave. User-defined test code
and data values can also be set.
The following table shows a message example when performing a loopback test with the slave 1 drive.
Command Message
Slave Address
Function Code
Upper
Test Code
Lower
Upper
Data
Lower
Upper
CRC-16
Lower
YASKAWA ELECTRIC SIEP C710636 04D U1000 Industrial MATRIX Drive Technical Manual
Response Message (normal)
02H Slave Address
03H Function Code
00H Data Quantity
20H
1st storage
register
00H
04H
Next storage
register
45H
F0H
Next storage
register
Next storage
register
CRC-16
01H
08H
00H
00H
A5H
37H
DAH
8DH
02H Slave Address
03H Function Code
08H Error Code
Upper 00H
CRC-16
Lower 65H
Upper 00H
Lower 00H
Upper 00H
Lower 00H
Upper 01H
Lower F4H
Upper AFH
Lower 82H
Slave Address
Function Code
Test Code
Data
CRC-16
C.8 Message Examples
Response Message (fault)
02H
83H
03H
Upper F1H
Lower 31H
Response Message
01H
08H
Upper 00H
Lower 00H
Upper A5H
Lower 37H
Upper DAH
Lower 8DH
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