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We have a new image of Raspbian with kernel patched with a real-time patch from Ingo Molnar available for download. It is useful for projects that require stable low latencies – max latency with PREEMPT-RT kernel on Raspberry is around ~70 microseconds (without any overclocking). The image was tested for compatibility with Raspberry Pi Model B and Raspberry Pi Model B+.
The image is not intended for general purpose use but rather for embedded electronics projects.
List of changes includes:
- Added RT_PREEMPT kernel(/boot/kernel-rt.img)
- Placed kernel source patched with rt-patch in /usr/src/
- Enabled SPI
- Enabled I2C
- Increased I2C speed to 400KHz
- Installed I2C-tools
- Installed pigpio (https://github.com/joan2937/pigpio)
- Installed rpi-serial-console (https://github.com/lurch/rpi-serial-console)
- Installed socat
- Installed screen
- Due to the required options some USB keyboards may not work
Thanks to Egor Fedorov and Jonathan Seawright for their work on compiling the RT kernel.