Description IIC I2C interface to expander GPIOs, add ADC read and DAC output. On board IO expanders IC PCF8574T, provide extra 8 IO ports. IO P0 P1 P2 P3 P4 are connected to joystick, corresponding to left, down, press, right and up. Joystick common pin can connect to VCC or GND, to ease your programming. Selectable by backside jumper, default to ground. IO P5 is connect to a buzzer. This can be disconnected by on board jumper. IO P6 P7 are not connected to anythings. On board ADC expander IC PCF8591, provide extra 4 analog read. AIN0 AIN1 are not connected to anythings. AIN2 connects to any analog sensor read port, default mount an analog sensor. Can be disconnected via jumper. AIN3 connects to on board trim pot potentiometer, for testing purpose only. Can be disconnected via jumper. On board power LDO, and logic shiftier for IIC. LDO supply up to 500mA/16V. Two groups of 3.3V, GND, SCL, SDA pins, cascadable design, can connect as many IIC devices as you want. All documentation please see on this page.
