C.9 Message Examples
C.9 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.
Slave Address
Command Message
02H
Function Code 03H
Starting No.
Data Quantity
CRC-16
Upper
Lower
Upper
Lower
Upper
Lower
00H
20H
00H
04H
45H
F0H
Response Message (normal)
Slave Address 02H
Function Code 03H
Data Quantity
1st storage register
Next storage register
Upper
Lower
Upper
08H
00H
65H
00H
Next storage register
Lower
Upper
Lower
Upper
00H
00H
00H
01H
Next storage register Lower F4H
CRC-16
Upper
Lower
AFH
82H
Slave Address
Response Message (fault)
02H
Function Code 83H
Error Code
CRC-16
Upper
Lower
03H
F1H
31H u
Loopback Test
Function code 08H performs a loopback test. This test returns a response message with exactly the same content as the command message and can be used to check the communications between the master and slave. User-defined test code and data values can be set.
The following table shows a message example when performing a loopback test with the slave 1 drive.
Command Message
Slave Address 01H
Function Code 08H
Test Code
Data
CRC-16
Upper
Lower
Upper
Lower
Upper
Lower
00H
00H
A5H
37H
DAH
8DH
Response Message (normal)
Slave Address 01H
Function Code 08H
Test Code
Data
CRC-16
Upper
Lower
Upper
Lower
Upper
Lower
00H
00H
A5H
37H
DAH
8DH
Response Message (fault)
Slave Address 01H
Function Code 89H
Error Code
CRC-16
Upper
Lower
01H
86H
50H
YASKAWA TOEP YAIQPM 03B YASKAWA AC Drive - iQpump Micro User Manual 399
MEMOBUS/Modbus Communications
C
C.9 Message Examples u
Writing to Multiple Registers
Function code 10h allows the user to write multiple drive MEMOBUS/Modbus registers with one message. This process works similar to reading registers, i.e., the address of the first register that is to be written and the data quantity must be set in the command message. The data to be written must be consecutive so that the register addresses are in order, starting from the specified address in the command message. The data order must be high byte, then lower byte.
The following table shows an example of a message where a forward operation has been set with a frequency reference of
60.00 Hz for the slave 1 drive.
If parameter values are changed using the Write command, depending on the setting of H5-11, an Enter command will be necessary to activate the data or save them.
Refer to H5-11: Communications Enter Function Selection on page 394 and
Refer to Enter Command on page 415
for detailed descriptions.
Slave Address
Command Message
01H
Function Code
Starting No.
Data Quantity
Number of Bytes
Upper
Lower
Starting Data
Upper
Lower
Upper
Lower
10H
00H
01H
00H
02H
04H
00H
01H
Response Message (normal)
Slave Address 01H
Function Code
Starting No.
Data Quantity
Upper
Lower
Upper
10H
00H
01H
00H
CRC-16
Lower
Upper
Lower
02H
10H
08H
Response Message (fault)
Slave Address 01H
Function Code
Error Code
CRC-16
Upper
Lower
90H
02H
CDH
C1H
Upper
Next Data
17H
CRC-16
Note:
Lower
Upper
Lower
70H
6DH
67H
For the number of bytes in the command message, take double the number of the data quantity.
400 YASKAWA TOEP YAIQPM 03B YASKAWA AC Drive - iQpump Micro User Manual
