Hi everyone,

I am building a universal cable tester using an ESP32 (3.3V logic/power).

The continuity and short-circuit testing is fully functional using 5x MCP23017 I/O expanders to handle 40 pins.

The Goal:

I want to add resistance measurement to detect degraded contacts or bad solders (mΩ to ...

Hello everyone,

I’m working on a **universal cable tester project** using an **ESP32 DevKit V1**, a **MCP23017 (I2C)** expander, a **ST7735 TFT display (128×160)**, and a **rotary encoder**.
My goal is to detect cable connections (40 Pins tester) by scanning continuity between the pins (GPA ↔ GPB ...