In mnr/rpigpior: Provides R with Access to the Raspberry Pi

knitr::opts_chunk$set(
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rpigpior

rpigpior allows the R programming language access to the Raspberry Pi GPIO using libgpiod. Because libgpiod is already included in Raspbian, there is nothing else to install.

rpigpior provides these tools:

• is.rpi - Returns TRUE if this code is running under Raspbian
• rpi_get - Returns the value of a board level pin (1-40) or an error if the pin isn't a data line (3.3v, 5v, or GROUND)
• rpi_set - Sets a pin to on or off
• rpi_monitor - watches a pin for a number of rising or falling events
• rpi_pwm - provides diagnostics and support for hardware pulse width modulation
• rpi_i2c_get - retrieve a value from an i2c connection
• rpi_i2c_set - set an i2c register to a value

Installation

rpigpior is hosted on github. Until it arrives at cran, you can install the development version of rpigpior from GitHub with:

library(remotes)
remotes::install_github("mnr/rpigpior")

Most documentation will tell you to use devtools, but install.packages("devtools") on a Raspberry Pi is an onerous task.

However...if you installed R on your Raspberry Pi using r4pi, you can use devtools just like normal.

# Start R with "sudo R" to install packages
# install.packages("devtools")

# You might want to switch back to non-admin R
library(devtools)
install_github("mnr/rpigpior")

Once you've installed, use library just like any other R package:

library(rpigpior)

Is this a Raspberry Pi?

It's helpful to check if your code is running on a Raspberry Pi.

if ( is.rpi() ) {
   print("Yes, this is a RPi")
} else {
   print ("No, this is not a RPi")
}

Reading a pin

If you connect a switch to board pin 40, this code will read it:

library(rpigpior)

rpi_get(40) # reads board pin 40
rpi_get(c(7,40)) # reads board pins 7 and 40

> GPIO004  GPIO21
        0       1

That assumes the switch to board pin 40 is "pushed" or closed. By the way, there is a diagram of this located in the articles section of the website (as identified in the package description)

Turning pins on and off

If you have a LEDs connected to board pin 19, 21, and 23, this code will turn them on, then one of them off, then all of them off

library(rpigpior)

toggleThese <- c(19,21,23)
rpi_set(toggleThese,1)
Sys.sleep(1)
rpi_set(toggleThese, c(1,0,1))
Sys.sleep(1)
rpi_set(toggleThese, 0)

Citation:

citation("rpigpior")

Related notes:

Related mailing list: linux-gpio\@vger.kernal.org

mnr/rpigpior documentation built on May 3, 2024, 12:14 a.m.