<![CDATA[Issue with unit 4 relay on cores3]]>Hello, I have a unit 4-relay, which works when connected to an atom-lite, but not when connected to a cores3 (SE lite)

Here is the config for the cores3 and atom-lite.

On the cores3 (module connected through port A), I see no devices found on i2c scan. It finds OK on the atom-lite

[17:35:54.929][C][i2c.idf:093]: I2C Bus:
[17:35:54.932][C][i2c.idf:094]:   SDA Pin: GPIO2
[17:35:54.932][C][i2c.idf:094]:   SCL Pin: GPIO1
[17:35:54.932][C][i2c.idf:094]:   Frequency: 50000 Hz
[17:35:54.935][C][i2c.idf:104]:   Recovery: bus successfully recovered
[17:35:54.935][C][i2c.idf:114]: Results from bus scan:
[17:35:54.939][C][i2c.idf:116]: Found no devices
[17:35:54.940][C][unit4relay:028]:   Address: 0x26
[17:35:54.940][C][unit4relay:030]: Switch:
[17:35:54.945][C][unit4relay:092]:   Relay 1 'Base Relay Channel 1'
[17:35:54.945][C][unit4relay:092]:     Restore Mode: restore defaults to OFF
[17:35:54.946][C][unit4relay:157]:     Icon: 'mdi:flash'
[17:35:54.946][C][unit4relay:163]:     Device Class: 'switch'
[17:35:54.950][C][unit4relay:092]:   Relay 2 'Base Relay Channel 2'
[17:35:54.950][C][unit4relay:092]:     Restore Mode: restore defaults to OFF
[17:35:54.952][C][unit4relay:157]:     Icon: 'mdi:flash'
[17:35:54.952][C][unit4relay:163]:     Device Class: 'switch'
[17:35:54.959][C][unit4relay:092]:   Relay 3 'Base Relay Channel 3'
[17:35:54.959][C][unit4relay:092]:     Restore Mode: restore defaults to OFF
[17:35:54.960][C][unit4relay:157]:     Icon: 'mdi:flash'
[17:35:54.960][C][unit4relay:163]:     Device Class: 'switch'
[17:35:54.963][C][unit4relay:092]:   Relay 4 'Relay Channel 4'
[17:35:54.963][C][unit4relay:092]:     Restore Mode: restore defaults to OFF
[17:35:54.963][C][unit4relay:157]:     Icon: 'mdi:flash'
[17:35:54.963][C][unit4relay:163]:     Device Class: 'switch'
[17:35:54.969][E][component:255]:   unit4relay is marked FAILED: unspecified

esphome:
  name: relay-test
  friendly_name: relay-test

esp32:
  board: esp32-s3-devkitc-1
  framework:
    type: arduino

(... logger, api, wifi, ota, captive portal)
    
external_components:
  - source: github://m5stack/esphome-yaml/components@main
    components: unit4relay
    refresh: 0s

i2c:
  - id: i2c_bus 
    sda: GPIO2
    scl: GPIO1
    scan: true 

# M5Stack 4-Relay Module - each relay at its own address

unit4relay:
  i2c_id: i2c_bus

switch:
  - platform: unit4relay
    relay_1:
      name: "Base Relay Channel 1"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_2:
      name: "Base Relay Channel 2"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_3:
      name: "Base Relay Channel 3"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_4:
      name: "Relay Channel 4"
      restore_mode: RESTORE_DEFAULT_OFF

And here for the atom (only different board and i2d ports)

esphome:
  name: relay-test
  friendly_name: relay-test

esp32:
  board: esp32dev
  framework:
    type: arduino

(... logger, api, wifi, ota, captive portal)
    
external_components:
  - source: github://m5stack/esphome-yaml/components@main
    components: unit4relay
    refresh: 0s

i2c:
  - id: i2c_bus 
    sda: GPIO26
    scl: GPIO32
    scan: true 

# M5Stack 4-Relay Module - each relay at its own address

unit4relay:
  i2c_id: i2c_bus

switch:
  - platform: unit4relay
    relay_1:
      name: "Base Relay Channel 1"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_2:
      name: "Base Relay Channel 2"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_3:
      name: "Base Relay Channel 3"
      restore_mode: RESTORE_DEFAULT_OFF
    relay_4:
      name: "Relay Channel 4"
      restore_mode: RESTORE_DEFAULT_OFF
]]>https://community.m5stack.com/topic/8126/issue-with-unit-4-relay-on-cores3RSS for NodeWed, 29 Apr 2026 08:44:35 GMTMon, 09 Mar 2026 17:40:26 GMT60<![CDATA[Reply to Issue with unit 4 relay on cores3 on Mon, 09 Mar 2026 19:57:31 GMT]]>On the cores3 (module connected through port A), I see no devices found on i2c scan when using esphome. It finds OK on the atom-lite.
If using the "Cores3 test" binary from m5stack, I can see the address found on the i2c scan app.

]]>https://community.m5stack.com/post/30749https://community.m5stack.com/post/30749Mon, 09 Mar 2026 19:57:31 GMT