12-24-2025, 03:07 PM
KC868-Server v1.5 – internal ESP32 ↔ ARM (STM32) serial connection?
Hi KinCony team,
We are working with a KC868-Server v1.5 board and trying to confirm the internal communication path between the ESP32 and the ARM (STM32) CPU.
Based on previous replies and documentation, we understood that ESP32 communicates with the ARM CPU via a serial port (STRING protocol). However, on our KC868-Server v1.5 hardware:
We tested ESP32 UART using GPIO16 / GPIO17, including swapping RX/TX, and tested multiple baud rates.
No data is ever received back from the ARM CPU.
With power off, we performed continuity testing and cannot find any electrical continuity between ESP32 GPIO16/17 (or any other ESP32 GPIO) and the STM32 pins, except for common GND pins.
This suggests that on KC868-Server v1.5, there may be no internal ESP32 → ARM serial connection.
Interestingly, with Kincony firmware on esp32, we can control the MOSFETs no problem. Is there an intermediary GPIO enable pin?
Could you please confirm:
Whether an internal ESP32 ↔ ARM serial connection exists on KC868-Server v1.5?
If yes, which ESP32 GPIOs and STM32 pins are connected?
Or if ESP32 is not intended to directly control the ARM CPU on this model?
If you have an example ESPHome yaml file, this would be extremely useful.
Thanks for helping clarify the intended hardware architecture.
Hi KinCony team,
We are working with a KC868-Server v1.5 board and trying to confirm the internal communication path between the ESP32 and the ARM (STM32) CPU.
Based on previous replies and documentation, we understood that ESP32 communicates with the ARM CPU via a serial port (STRING protocol). However, on our KC868-Server v1.5 hardware:
We tested ESP32 UART using GPIO16 / GPIO17, including swapping RX/TX, and tested multiple baud rates.
No data is ever received back from the ARM CPU.
With power off, we performed continuity testing and cannot find any electrical continuity between ESP32 GPIO16/17 (or any other ESP32 GPIO) and the STM32 pins, except for common GND pins.
This suggests that on KC868-Server v1.5, there may be no internal ESP32 → ARM serial connection.
Interestingly, with Kincony firmware on esp32, we can control the MOSFETs no problem. Is there an intermediary GPIO enable pin?
Could you please confirm:
Whether an internal ESP32 ↔ ARM serial connection exists on KC868-Server v1.5?
If yes, which ESP32 GPIOs and STM32 pins are connected?
Or if ESP32 is not intended to directly control the ARM CPU on this model?
If you have an example ESPHome yaml file, this would be extremely useful.
Thanks for helping clarify the intended hardware architecture.