MODBUS TCP/IP write multiple registers

Configuration
1

hi, i would like to write in multiple registers with funtion code 16 (0x10) some values (integer 16 bit signed).
for example:
I need to write this:
address 28301 value 1
address 28302 value 1
address 28303 value 6

I expect an output packet formatted like this (HEX):
[TCP]>Tx > 13:30:07:747 - 00 01 00 00 00 0D 01 10 6E 8D 00 03 06 00 01 00 01 00 06

10 → function code
6E 8D → Starting address (28301 in HEX)
00 03 → quantity of register
06 → byte count
00 01 00 01 00 06 → value

I try to set that in the service tool to development area in Home assisistan:

service: modbus.write_register
data:
  hub: modbustcp1
  address: 28301
  unit: 1
  value:
    - 1
    - 1
    - 6

but it doesn’t work…
P.S. I can read all the registers with sensor whitout any problems

Can anyone help me?

2 
service: modbus.write_register
data:
  address: <target register address>
  unit: <target slave address>
  hub: <hub name>
  value: [0x4120, 0x0000]
3

tankyou for the answere, but it’s the same to this, and doesn’t work:

service: modbus.write_register
data:
  address: <target register address>
  unit: <target slave address>
  hub: <hub name>
  value: 
    - 16672
    - 0
4

Is this for a fancoil? I am trying to send commands to it and I can’t make it. I am asking because the addresses and integers are the same with what I am tying to do.

5

Yes it is. I solved it by creating scripts like this:

alias: Velocità 1 climatizzatore camera
sequence:
  - service: modbus.write_register
    data:
      hub: modbustcp1
      address: 28301
      unit: 3
    data_template:
      value:
        - 1
        - "{{states('sensor.modalita_climatizzatore_camera')}}"    
        - 2
mode: queued
max: 10
icon: mdi:fan-speed-1

I also had the problem that too many calls to the sensors saturated the line

2 Likes
6

I just found that my fan coil (Phnix is the maker) accepts writes with function code 10. That means that instead of write_type: holding I have to put write_type: holdings

From HA documentation

image

image
image1387×203 8.83 KB 

      - name: "Phnix Living Room ON/OFF"
        unique_id: phnix_living_room_on/off
        slave: 15
        address: 28301
        command_on: 1
        command_off: 0
        scan_interval: 10
        write_type: holdings        
        verify:

Of course I am not finished yet, I have to find out how to make the fan speed adjustments, set temperatures etc.
Also there is a big delay on my commands…

7

Ciao!!!
Ho gli stessi indirizzi tuoi per il mio fancoil, di che marca è il tuo? perché il mio è della IdealClima ma effettivamente non ha tanti registri da poter leggere, per esempio la funzione ventilazione non mi va.

8

Hi, I’m also working on the ideal clima fan coils and I’m having a lot of problems writing the registers. If you have information, please share, I’ll share mine. Thank you.