Preset Multiple Registers (10 Hex); Read/Write Multiple Registers (17 Hex) - Danfoss VLT HVAC Basic Drive FC 101 Design Manual

RS485 Installation and Set-...
Response
The normal response is an echo of the query, returned
after the register contents have been passed.
Field name
Slave address 01
Function 06
Register address HI 03
Register address LO E7
Preset data HI 00
Preset data LO 01
Error check (CRC) –
Table 7.31 Response

7.10.6 Preset Multiple Registers (10 hex)

Description
This function presets values into a sequence of holding
registers.
Query
The query telegram specifies the register references to be
preset. Register addresses start at 0, that is, register 1 is
addressed as 0. Example of a request to preset 2 registers
(set parameter 1-24 Motor Current to 738 (7.38 A)):
Field name
Slave address
Function
Starting address HI
Starting address LO
Number of registers HI
Number of registers LO
Byte count
Write data HI (Register 4: 1049)
Write data LO (Register 4: 1049)
Write data HI (Register 4: 1050)
Write data LO (Register 4: 1050)
Error check (CRC)
Table 7.32 Query
Response
The normal response returns the slave address, function
code, starting address, and quantity of registers preset.
Field name
Slave address
Function
Starting address HI
Starting address LO
Number of registers HI
Number of registers LO
Error check (CRC)
Table 7.33 Response
MG18C702
Design Guide
7.10.7 Read/Write Multiple Registers (17
Description
Example (hex)
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
zero. 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):
Slave address
Function
Reading starting address HI
Read starting address LO
Quantity to read HI
Quantity to read LO
Example (hex)
Write starting address HI
01
Write starting address LO
10
Quantity to write HI
04
Quantity to write LO
07
00
Write byte count
02
Write registers value HI
04
Write registers value LO
00
Write registers value HI
00
Write registers value LO
02
Error check (CRC)
E2
–
Response
The normal response contains the data from the group of
registers that were read. The byte count field specifies the
quantity of bytes to follow in the read data field.
Example (hex)
Slave address
01
Function
10
Byte count
04
Read registers value HI
19
Read registers value LO
00
Read registers value HI
02
Read registers value LO
–
Error check (CRC)
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hex)
Field name
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
04
00
00
02
0E
–
Table 7.34 Query
Field name
Table 7.35 Response
Example (hex)
7
Example (hex)
01
17
04
00
00
C3
50
–
95
7