The TKJHAT is an educational add-on board for the Raspberry Pi Pico / Pico 2 to be used within in the course Computer Systems and Introduction to Computer Systems in University of Oulu.
This SDK provides a minimal C API for working with the onboard sensors and actuators.

Actuators

Device	Interface	Notes
Red LED	GPIO 14	Onboard indicator LED (also referred to as “onboard LED”)
RGB LED	GPIO 18:R, 19:G, 20:B	Common-anode LED, driven via PWM
Buzzer	GPIO 17	Digital output, simple square-wave control
OLED display (SSD1306)	I²C (0x3C)	128×64 pixels, text & graphics via SSD1306 datasheet

Sensors

Sensor	Interface	Address	Datasheet
Ambient light sensor (VEML6030)	I²C	0x10	Vishay VEML6030
Temperature & humidity (HDC2021)	I²C	0x40	TI HDC2021
IMU (ICM-42670, accel+gyro)	I²C	0x69	TDK ICM-42670
PDM MEMS Microphone	GPIO 16 (DATA), GPIO 15 (CLK)	—	Uses PIO + Arm Developer Pico microphone library

Notes

The default I²C bus uses SDA = GPIO 12 and SCL = GPIO 13.
The SDK is intended for teaching: APIs are simplified, and defaults (e.g. 100 Hz ODR, ±4 g accelerometer) are chosen to be practical.

Authors

Raisul Islam
Iván Sánchez Milara

Contributors

Emil Kelhala - Help in initial testing.