Unable to connect LilyGo T-CAN485 to F1245

[jordglob]

Hi!
I'm trying to connect my Nibe F1245 via NibeGW using a LilyGo T-CAN485 v1.1 board. Data is clearly flowing into the ESP32 when MODBUS is activated on the heat pump, but the packets seem to get corrupted/misread, causing Home Assistant to throw "Error on read request".

error message from HA nibe heat pump integration "Fel på läsförfrågan från pumpen. Verifiera din "Fjärrläsningsport" eller "Fjärr-IP-adress"

reapeated tries multible times but alway end up with the red light below the display in the end.

Build Environment:
I was unable to compile the project via the ESPHome Add-on inside Home Assistant due to dependency/versioning issues. Instead, the compilation and flashing was successfully done locally on my Windows machine using VS Code.
The Logs:
As soon as the heat pump communicates, the VS code terminal starts roling: Here is a snippet from the log:
......
[16:21:56.520][D][nibeGW:097]: Ignoring byte D4
[16:21:56.524][D][nibeGW:097]: Ignoring byte BF
[16:21:56.530][D][nibeGW:097]: Ignoring byte 29
[16:21:56.542][D][nibeGW:097]: Ignoring byte FF
[16:21:56.542][D][nibeGW:097]: Ignoring byte 69
[16:21:56.547][D][nibeGW:097]: Ignoring byte 00
.....
This starts and stops when modbus is toggled from nibe display.

Heat Pump: Nibe F1245 (Firmware 7740R4).
Board: LilyGo T-CAN485 (v1.1), powered by an isolated 5V USB wall charger. Connected to AA3-X4 (GND, A, B).
Network: Home Assistant OS is running in VirtualBox on a Windows host (Bridged Adapter, so no NAT blocking). Pinging the LilyGo from inside the HA console fuctions.
The ESPHome Config:
To be as transparent as possible, I have split my config into two parts below. The first part is copied straight from the lilygo-t-can485.yaml example in this repository. The second part is what I have added to make the UDP gateway work.

Yaml

---------------------------------------------------------

PART 1: OFFICIAL CODE FROM ELUPUS' GITHUB EXAMPLE

---------------------------------------------------------

external_components:

• source: github://elupus/esphome-nibe@master

output:

• platform: gpio
  id: ENABLE_PIN
  pin:
  number: GPIO19
  inverted: true
• platform: gpio
  id: SE_PIN
  pin:
  number: GPIO17
  inverted: true
• platform: gpio
  id: ENABLE_5V_PIN
  pin:
  number: GPIO16
  inverted: true

uart:
id: modbus_uart
rx_pin: GPIO21
tx_pin: GPIO22
baud_rate: 9600

---------------------------------------------------------

PART 2: CODE ADDED BY ME FOR WIFI & NIBEGW

---------------------------------------------------------

wifi:
ssid: "airport"
password: "***"
power_save_mode: none

nibegw:
uart_id: modbus_uart

Note: dir_pin is intentionally omitted here because the SE_PIN (GPIO17)

above handles the hardware auto-direction for the LilyGo chip.

udp:
target:
- ip: 192.168.38.118
port: 9999

My Question:
is it ok to run the HA nibe heat pump in a vitual mashine?
Any pointers on how to get the handshake working would be highly appreciated!

[elupus]

No need to do anything with home assistant until you can turn on modbus on the pump without errors.

Did you maybe swap the a/b channels?

[elupus]

Also what build error did you get?

[jordglob]

Thanks for the reply!

I tried A/B both way and can only see trafic when B meassueres ca 0,1vdc higher then A. Gnd-> A = 1.59 and B = 1,69

When I am home again end of this week I can upload a screen shot of the red lines inside of ESPhome during compiling. Tried to follow the steps in issue #56 but its works differently on my setup.

[jordglob]

I did a new try just now remotley. not at all shure I do the correct steps and sorry for the format of the text, new also to github...
1.

2.

3. install/Wirelessly

Nibe.yaml:

esphome:
  name: nibegw
  comment: Nibegw

esp32:
  board: esp32dev
  framework:
    type: esp-idf

# General ESPHome setup
api:
  reboot_timeout: 0s

ota:
  - platform: esphome
    password: XXX

logger:

wifi:
  ssid: airport
  password: XXX
  fast_connect: true # Fast connect to connect to my hidden network
  # It is recommended to disable powersave mode on wifi, to make sure the device does not miss UDP requests sent.
  power_save_mode: none
  # The device needs a static IP. Either do that here with the manual_ip node, or do it via another way (router)

# Load nibe component
external_components:
  - source: github://elupus/esphome-nibe

# Set pins required for LilyGo T-CAN485 board
output:
  - platform: gpio
    id: ENABLE_PIN # Enable the chip
    pin:
      number: GPIO19
      inverted: true
  - platform: gpio
    id: SE_PIN # Enable autodirection
    pin:
      number: GPIO17
      inverted: true
  - platform: gpio
    id: ENABLE_5V_PIN # Enable 5V pin for RS485 chip
    pin:
      number: GPIO16
      inverted: true

# Configure uart that will be used
uart:
  rx_pin: GPIO21
  tx_pin: GPIO22
  baud_rate: 9600

# Configure NibeGW
nibegw:
  udp:
    # List of source address to accept data from, may be empty for no filter
    source:
      - 192.168.255.254

    # Optional port this device will listen to to receive read requests. Defaults to 9999
    # read_port: 9999

    # Optional port this device will listen to to receive write request. Defaults to 10000
    # write_port: 10000

  acknowledge:
    - MODBUS40

  # Constant replies to certain requests cabe made
  constants:
    - address: MODBUS40
      token: ACCESSORY
      data: [
            0x0A, # MODBUS version low
            0x00, # MODBUS version high
            0x01, # MODBUS address?
      ]

# Some helper functions to restart ESPHome from HA
button:
- platform: restart
  name: Nibegw Restart
- platform: safe_mode
  name: Nibegw Safe Mode Boot

[elupus]

Right, your esphome addon is too old. Just update that.

[jordglob]

Changed to esphome dev version and updated HA OS to 17:

and another try with diffrent faults:

[elupus]

That looks funky, but not related to this module. You should not need dev version. Last release should be fine.

Does your virtual machine have enough memory? Something is breaking bad there.

[jordglob]

now it compiles after also upgraded HA core to latest version. I probaly need to reread #56 or connect via USB the first time flashing the lilygo.

[jordglob]

I just wanted to drop a quick update and confirm that the integration is now working perfectly for me!

If anyone else is experiencing constant [D][nibegw:097]: Ignoring byte XX errors in the logs (along with "Read request from pump failed" in Home Assistant), the issue for me seems hardware/noise-related, specifically regarding the ground reference.

The fix: I had to connect the GND from the heat pump (X44 terminal) to the GND pin on the RS485 screw terminal. Additionally, I had to physically bridge (add a jumper wire between) the RS485 GND terminal and the main board's GND (- pin on the top power terminal) to ensure both the RS485 chip and the ESP32 shared the exact same stable ground reference.

As soon as they were bridged, I started getting clean Response to address: 0x20 token: 0x69 logs.

So running Nibe in Home Assistant in a virtual mashine works great!