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HC12Lib

A C library for Freescale's CodeWarrior containing interrupt-driven drivers for different peripherals of the MC9S12XDP512 microcontroller and some devices that use them. It offers support for:

• RTI (Real Time Interrupt)
• I2C
• SPI
• Input Capture / Output Compare
• PWM
• Analog to Digital Conversion
• A Hitachi HD44780 based LCD
• An MPU-6050 motion sensor (gyroscope + accelerometer)
• An HC-SR04 ultrasonic distance sensor
• A DS1307 RTC (Real Time Clock)
• Generic RF transmitters and receivers (315 / 433 MHz)
• Nordic Semiconductor's nRF24L01+ 2.4 GHz transceivers
• An infrared remote control using the RC-5 protocol

There's also specialized modules that use some of the above peripherals, such as a Battery module that samples a number of batteries voltages and informs of low battery conditions, an analog 4-axis joystick, and an interface for remotely controlling a quadrotor using said joystick, printing information on an LCD screen and using the nRF to transmit the sampled data.