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Wiring Reference: CN105 to Grove

Pinout and wiring reference for connecting an M5Stack Atom S3 Lite or NanoC6 to a Mitsubishi heat pump CN105 port.

Assembled CN105-to-Grove cable with a 5-pin JST connector on one end and a 4-pin Grove HY2.0 connector on the other

Shortcut: Buy a Ready-Made Cable

This page is a reference for building the cable yourself. Prefer not to? Buy a ready-made CN105-to-Grove cable — no crimping or soldering required — or get the complete Serin Controller with the cable included.

Wiring Diagram

CN105 to Grove Wiring Diagram Wiring diagram showing connections between the CN105 5-pin JST connector on a Mitsubishi HVAC unit and the 4-pin Grove HY2.0 connector on an ESP32 controller. Black wire: GND to GND. Red wire: 5V to 5V. White wire: CN105 TX to Grove RX (GPIO 2). Yellow wire: CN105 RX to Grove TX (GPIO 1). CN105 (HVAC Side) Pin 1 Pin 1 · 12V not used Pin 2 · GND Pin 3 · 5V Pin 4 · TX Pin 5 · RX JST-PAP-05V-S Grove (Device Side) Pin 1 Pin 1 · GND Pin 2 · 5V Pin 3 · RX GPIO 2 Pin 4 · TX GPIO 1 HY2.0-4P (Grove) Black Red White Yellow Ground Power HVAC TX → ESP RX ESP TX → HVAC RX

Cable Options

You may use the information above to build your own cable using these parts:

Prefer not to build one? Buy a ready-made CN105-to-Grove cable, or get the complete Serin Controller with the cable included. For a full shopping list including boards, see the parts list.

JST PAP-05V-S connector (5-pin white housing) on left and HY2.0-4P Grove connector (4-pin white housing) on right
Detailed Pinout Reference

CN105 (JST-PAP-05V-S) Pinout

Pin Signal Description
112VNot used
2GNDGround
35V5V Power
4TXData output from HVAC (5V logic)
5RXData input to HVAC (5V logic)

Grove (HY2.0-4P) Pinout for M5Stack Atom S3 Lite and NanoC6

Pin Signal Description
1GGround (connects to ESP32 GND)
25V5V Power (connects to ESP32 5V/VCC)
3G2RX (connects to ESP32 UART RX pin)
4G1TX (connects to ESP32 UART TX pin)

References

Disclaimer

Always turn off power to your HVAC unit before connecting or disconnecting any cables. This reference is provided as-is. Wiring is at your own risk.