Reference

Library

• DFRobot_RaspberryPi_Expansion_Board
• DFRobot_VEML6075
• DFRobot_Gesture_Touch
• smbus2 (IIC Learning Guide)
• spidev (SPI Learning Guide)
• GPIO Learning Guide

API Description

• DFRobot_RaspberryPi_Expansion_Board Library:
  • begin(): Initialize the board.
  • get_adc_value(channel): Get ADC value from specified analog channel (A0-A3).
  • set_pwm_duty(channel, duty): Set PWM duty cycle for specified channel (0-3 or ALL).
  • set_pwm_frequency(freq): Set PWM frequency.
• DFRobot_VEML6075 Library:
  • begin(): Initialize the VEML6075 sensor.
  • getUva(): Get UVA value.
  • getUvb(): Get UVB value.
  • getUvi(Uva, Uvb): Calculate UVI from UVA and UVB values.
  • Uvi2mwpcm2(Uvi): Convert UVI to mW/cm².
• DFRobot_Expansion_Board_Servo Library:
  • move(channel, angle): Move servo to specified angle (0-180) for specified channel (0-3 or ALL).

Principle

• Raspberry Pi GPIO pins work with a maximum logic level of 3.3V.
• The board integrates an STM32 main controller to handle IO expansion.
• Analog ports use a 12-bit ADC to convert analog signals to digital data, sent to Raspberry Pi via IIC.
• PWM ports are controlled via IIC from Raspberry Pi, with support for external power supply (6-12V).

Other Supplementary Information

Note:

• The GPIO number in this board adopts BCM codes.
• When the VP port is not power by external power, the voltage of PWM ⊕ is 5V.
• When the VP port is powered by external power, the voltage of PWM ⊕ is equal to that of the VP external power (6-12V).