In order to compile this library, you may need to install: If you must use bcm2835_gpio_len() and friends, make sure you disable the pins with bcm2835_gpio_clr_len() and friends after use. Reason for this is not yet determined, but we suspect that an interrupt handler is hitting a hard loop on those OSs.

CAUTION: it has been observed that when detect enables such as bcm2835_gpio_len() are used and the pin is pulled LOW it can cause temporary hangs on -wheezy-raspbian, -wheezy-raspbian and Occidentalisv01. Tested on debian6-19-04-2012, -wheezy-raspbian, -wheezy-raspbian and Occidentalisv01, Raspbian Jessie. Before asking a question or reporting a bug, please read Do not contact the author directly, unless it is to discuss commercial licensing. You can also find online help and discussion at Please use that group for all questions and discussions on this topic. The version of the package that this documentation refers to can be downloaded from You can find the latest version at It is C++ compatible, and installs as a header file and non-shared library on any Linux-based distro (but clearly is no use except on Raspberry Pi or another board with BCM 2835). Works with all versions of Debian up to and including Debian Buster 10. Works on all versions up to and including RPI 4. Pin event detection is supported by polling (interrupts are not supported). It provides functions for reading digital inputs and setting digital outputs, using SPI and I2C, and for accessing the system timers. It provides access to GPIO and other IO functions on the Broadcom BCM 2835 chip, as used in the RaspberryPi, allowing access to the GPIO pins on the 26 pin IDE plug on the RPi board so you can control and interface with various external devices. This is a C library for Raspberry Pi (RPi).

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