Force/Write Single Coil (05 Hex) - Danfoss VLT FC 102 Series Design Manual

Installation and Set-up
Example of a request to read coils 33–48 (Status Word)
from follower device 01.
Field Name
Follower Address
Function
Starting Address HI
Starting Address LO
No. of Points HI
No. of Points LO
Error Check (CRC)
Table 8.21 Query
Response
The coil status in the response message is packed as one
coil per bit of the data field. Status is indicated as: 1=ON;
0=OFF. The LSB of the first data byte contains the coil
addressed in the query. The other coils follow toward the
8 8
high order end of this byte and from 'low-order to high-
order' in subsequent bytes.
If the returned coil quantity is not a multiple of 8, the
remaining bits in the final data byte are padded with zeros
(toward the high order end of the byte). The byte count
field specifies the number of complete bytes of data.
Field Name
Follower Address
Function
Byte Count
Data (Coils 40-33)
Data (Coils 48-41)
Error Check (CRC)
Table 8.22 Response
NOTICE!
Coils and registers are addressed explicitly with an
off-set of -1 in Modbus.
For example, Coil 33 is addressed as Coil 32.
160
Design Guide
Example (HEX)
01 (adjustable frequency drive address)
01 (read coils)
00
20 (32 decimals) Coil 33
00
10 (16 decimals)
-
Example (HEX)
01 (adjustable frequency drive
address)
01 (read coils)
02 (two bytes of data)
07
06 (STW=0607hex)
-
Danfoss A/S © Rev. 06/2014 All rights reserved.

8.10.2 Force/Write Single Coil (05 HEX)

Description
This function forces the coil to either ON or OFF. When
broadcast, the function forces the same coil references in
all attached followers.
Query
The query message specifies the coil 65 (parameter write
control) to be forced. Coil addresses start at zero, that is,
coil 65 is addressed as 64. Force Data=00 00HEX (OFF) or
FF 00HEX (ON).
Field Name Example (HEX)
Follower Address 01 (adjustable frequency drive
address)
Function 05 (write single coil)
Coil Address HI 00
Coil Address LO 40 (64 decimal) Coil 65
Force Data HI FF
Force Data LO 00 (FF 00=ON)
Error Check (CRC) -
Table 8.23 Query
Response
The normal response is an echo of the query, which is
returned after the coil state has been forced.
Field Name
Follower Address
Function
Force Data HI
Force Data LO
Quantity of Coils HI
Quantity of Coils LO
Error Check (CRC)
Table 8.24 Response
Example (HEX)
01
05
FF
00
00
01
-
MG11BC22