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.

Peripherals connected to GPIO pins

Device	Interface	Pin name(s)	Notes
Red LED	GPIO 14	`RED_LED_PIN` / `LED1`	Onboard indicator LED (also referred to as “onboard LED”)
RGB LED	GPIO 18:R, 19:G, 20:B	`RGB_LED_R`, `RGB_LED_G`, `RGB_LED_B`	Common-anode LED, driven via PWM
Buzzer	GPIO 17	`BUZZER_PIN`	Digital output, simple square-wave control
PDM MEMS Microphone	GPIO 16 (DATA), GPIO 15 (CLK)	`PDM_DATA`, `PDM_CLK`	Uses PIO + Arm Developer Pico microphone library

Peripherals connected to I²C

The default I²C bus uses SDA = GPIO 12 (DEFAULT_I2C_SDA_PIN) and SCL = GPIO 13 (DEFAULT_I2C_SCL_PIN ).

Sensor	Interface	Address	Datasheet
Ambient light sensor (VEML6030)	I²C	VEML6030_I2C_ADDR (0x10)	Vishay VEML6030
Temperature & humidity (HDC2021)	I²C	HDC2021_I2C_ADDRESS (0x40)	TI HDC2021
IMU (ICM-42670, accel+gyro)	I²C	ICM42670_I2C_ADDRESS (0x69)	TDK ICM-42670
OLED display (SSD1306)	I²C	SSD1306_I2C_ADDRESS (0x3C)	SSD1306 datasheet

Notes

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.