Danfoss VLT Flow Drive FC 111 Design Manual page 124

VLT® Flow Drive FC 111
Design Guide
Field name
Write data LO (Register 4: 1049)
Write data HI (Register 4: 1050)
Write data LO (Register 4: 1050)
Error check (CRC)
Response
The normal response returns the follower address, function code, starting address, and quantity of registers preset.
Table 81: Response
Field name
Follower address
Function
Starting address HI
Starting address LO
Number of registers HI
Number of registers LO
Error check (CRC)
8.10.8 Read/Write Multiple Registers (17 hex)
Description
This function code performs a combination of 1 read operation and 1 write operation in a single MODBUS transaction. The write
operation is performed before read.
Query
The query message specifies the starting address and number of holding registers to be read as well as the starting address, number
of holding registers, and the data to be written. Holding registers are addressed starting at 0. Example of a request to set parameter
1-24 Motor Current to 738 (7.38 A) and read parameter 3-03 Maximum Reference which has value 50000 (50,000 Hz):
Table 82: Query
Field name
Follower address
Function
Reading starting address HI
Read starting address LO
Quantity to read HI
Quantity to read LO
Write starting address HI
Write starting address LO
Quantity to write HI
Quantity to write LO
124 | Danfoss A/S © 2021.04
Example (hex)
01
17
0B (Register address 3029)
D5 (Register address 3029)
00
02 (Parameter 3-03 Maximum Reference is 32 bits long, that is, 2 registers)
04 (Register address 1239)
D7 (Register address 1239)
00
02
RS485 Installation and Set-up
Example (hex)
00
02
E2
–
Example (hex)
01
10
04
19
00
02
–
AJ363928382091en-000101 / 130R0983