YASKAWA CR700

5.3 MEMOBUS/Modbus Communications
308 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual
Byte Command Message
Setting Data
(Hex.)
Response Message (Normal)
Setting Data
(Hex.)
Response Message (Fault)
Setting Data
(Hex.)
9 -
Next storage
register
Upper 01 -
10 - Lower F4 -
11 -
CRC-16
Upper AF -
12 - Lower 82 -
■ Loopback Test
The loopback test uses function code 08 (Hex.) and returns the command message as a response message. This
test checks communication between the master and slave. The test code and data can use desired values.
Table 5.7 shows examples of messages given out when the loopback test is done with the drive of slave 1.
Table 5.7 Message Examples from the Loopback Test
Byte Command Message
Setting Data (Hex.)
Response Message (Normal)
Setting Data (Hex.)
0 Slave address 01 Slave address 01
1 Function code 08 Function code 08
2
Test code
Upper 00
Test code
Upper 00
3 Lower 00 Lower 00
4
Data
Upper A5
Data
Upper A5
5 Lower 37 Lower 37
6
CRC-16
Upper DA
CRC-16
Upper DA
7 Lower 8D Lower 8D
■ Writing to Multiple Holding Registers
You can write the data that you set to the number of holding registers set in function code 10 (hex). You must
configure the number of the holding registers and each 8 higher bits and 8 lower bits in order in the command
message for the write data. You can write to a maximum of 16 holding registers.
Table 5.8 shows example messages when you use the PLC to set Forward run in the drive of slave 1 with a 60.00
Hz frequency reference.
When you rewrite the parameter value with the write command through the H5-11 [Comm ENTER Command
Mode] setting, you must use the Enter command to save and enable the contents of the changes. Refer to
H5-11:
Comm ENTER Command Mode on page 739 and Enter Command on page 311 for more information.
Table 5.8 Message Example When Writing to Multiple Holding Registers
Byte Command Message
Setting Data
(Hex.)
Response Message (When
Normal)
Setting Data
(Hex.)
Response Message (When
There is a Fault)
Setting Data
(Hex.)
0 Slave address 01 Slave address 01 Slave address 01
1 Function code 10 Function code 10 Function code 90
2
Starting No.
Upper 00
Starting No.
Upper 00 Error code 02
3 Lower 01 Lower 01
CRC-16
Upper CD
4
Data Quantity
Upper 00
Data Quantity
Upper 00 Lower C1
5 Lower 02 Lower 02 -
6 Byte No. 04
CRC-16
Upper 10 -
7
First data
Data Quantity
Upper 00 Lower 08 -
8 Lower 01 - -
9
Next data
Upper 17 - -
10 Lower 70 - -
11
CRC-16
Upper 6D - -
12 Lower B7 - -
Note:
The number of bytes set in the command message set the data quantity × 2 during the command message. The response message uses
the same formula.