Guides for GPIO in Xojo
Our guides are oriented to help users use GPIO in Xojo.
Note that many of our guides are still in our old guides which was oriented for using with the legacy wiringpi library.
The new guides use Gpiod Plugin (which uses libgpiod), I2C Plugin (which uses libi2c) and SPI Plugin.
GPIO
I2C
SPI
Connecting with button
Basic GPIO, simple wiring, asynchronous monitoring.
Uses Gpiod Plugin, async GPIO event monitoring.
This guide tests various of boards also.
GPIO pin behind transistor to get more current
And also dealing with undetermined state of the GPIO pin at boot time.
Uses Gpiod Plugin, basic GPIO.
GPIO pin behind optocoupler
Uses Gpiod Plugin, basic GPIO.
Infrared Motion Detection
Basic GPIO, simple wiring, asynchronous monitoring.
Uses Gpiod Plugin, async GPIO event monitoring.
4 pin RGB LED
Uses Gpiod Plugin, basic GPIO.
Relay board
Uses Gpiod Plugin, basic GPIO.
HD44780 based LCD
Guide about how to connect to and control
HD44780 displays. 16×2 or 20 x 4 displays. The guide also covers how to send custom Glyphs to the display.
Uses Gpiod Plugin, basic GPIO.
HD44780 based LCD (part 2 non standard sizes)
Follow-up guide on HD44780 displays, covering non standard sizes.
Uses Gpiod Plugin, basic GPIO.
BMP180 digital pressure sensor
Uses I2C Plugin, very simple wiring.
BMP280 digital pressure sensor
Uses I2C Plugin, very simple wiring.
HTU21DF temperature and humidity sensor
Uses I2C Plugin, very simple wiring.
LM75A temperature sensor
Uses I2C Plugin, very simple wiring.
MCP4725 12 bit digital to analog converter
Uses I2C Plugin, very simple wiring.
MCP3008 10 bit analog to digital converter
Uses SPI Plugin.
PCF8591 AD/DA bi-directional converter
Uses I2C Plugin.
LM393 Flame sensor
Uses Gpiod Plugin, basic GPIO.
SW420 Vibration sensor
Uses Gpiod Plugin, basic GPIO.
SW520D Tilt sensor
Uses Gpiod Plugin, basic GPIO.
Reed switch
Uses Gpiod Plugin, basic GPIO.
Legacy guides
Our legacy guides use the old Wiring Pi library.
If you want to help with making this archive of knowledge for Xojo Raspberry Pi developers then you can submit articles to us, your name would be put on it as author. We would try to reformat if needed it to fit the other articles and add links to how to use breadboard if your article uses such and so on.