Added RPi cheatsheets

CONTRIBUTING.md

@@ -179,6 +179,7 @@ Our competitive programming lists are not as strict about these exclusions. The
 
 We're not that fussy about book-ness. Here are some attributes that signify that a resource is a book:
 
+
 - it has an ISBN (International Standard Book Number)
 - it has a Table of Contents
 - a downloaded version, especially ePub, is offered
@@ -194,16 +195,19 @@ There are lots of books that we list that don't have these attributes; it can de
 
 Sometimes these can be hard to distinguish!
 
+
 Courses often have associated textbooks, which we would list in our books lists. Courses have lectures, exercises, tests, notes or other didactic aids. A single lecture or video by itself is not a course. A powerpoint is not a course.
 
 
+
 ##### Interactive Tutorials vs. Other stuff
 
 If you can print it out and retain its essence, it's not an Interactive Tutorial.
 
 
 ### Automation
 
+
 - Formatting rules enforcement is automated via [GitHub Actions](https://github.com/features/actions) using [fpb-lint](https://github.com/vhf/free-programming-books-lint) (see [.github/workflows/fpb-lint.yml](.github/workflows/fpb-lint.yml))
 - URL validation uses [awesome_bot](https://github.com/dkhamsing/awesome_bot)
 - To trigger URL validation, push a commit that includes a commit message containing `check_urls=file_to_check`:

more/free-programming-cheatsheets.md

@@ -22,6 +22,7 @@
 * [Perl](#perl)
 * [Python](#python)
 * [R](#r)
+* [Raspberry Pi](#raspberry-pi)
 * [Ruby](#ruby)
 * [Rust](#rust)
 * [SQL](#sql)
@@ -166,6 +167,15 @@
 * [All RStudio cheatsheets resources](https://www.rstudio.com/resources/cheatsheets) - RStudio.com (HTML site with PDF links)
 
 
+### Raspberry Pi
+
+* [Basic GPIO layout configuration cheatsheet](https://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/robot/cheat_sheet/) - University of Cambridge Computer Laboratory Raspberry Pi Projects Cheatsheet (PDF)
+* [Other Raspberry Pi Commands cheatsheet](https://www.raspberrypistarterkits.com/wp-content/uploads/2018/01/raspberry-pi-commands-cheat-sheet.pdf) - RPi starter Kit (PDF)
+* [Raspberry Pi Basics cheatsheet](https://www.woolseyworkshop.com/wp-content/uploads/WoolseyWorkshop_Cheatsheet_RaspberryPiBasics_v1.4.pdf) - Woolsey Workshop (PDF)
+* [Raspberry Pi Different GPIO Configuration Combinations cheatsheet](https://static.raspberrypi.org/files/education/posters/GPIO_Zero_Ceatsheet.pdf) - GPIO Zero Cheatsheet (PDF)
+* [Top 50 General Commands for Raspberry Pi cheatsheet](https://projects-raspberry.com/wp-content/uploads/2018/05/Top-50-Raspberry-pi-commands-List-cheat-sheet.pdf) - Projects Raspberry (PDF)
+
+
 ### Ruby
 
 * [Ruby Cheat Sheet](https://www.codeconquest.com/wp-content/uploads/Ruby-Cheat-Sheet-by-CodeConquestDOTcom.pdf) - CodeConquest.com (PDF)