raspberry-bare-metal

This repo is adapted from my ECS 251: Operating Systems at UC Davis

It is a bare-metal OS written from scracth, without OS and hence everything is under control, e.g., no process switching, etc.

I think it could be useful for projects that require precise real-time control. For example, simultaneously control multiple LED lights.

Target boards

Rasbperry Pi 2 and 3. They have four cores, and therefore you can use each core to do its own task.

Demo Application

• Core 0 as main controller, core 1-3 control R (GPIO 16) G (GPIO 20) B (GPIO21) three lights
• Interruption routine in core 0, software implementation of PWM for powering LEDs

Naming

• Files starts with dtc*** are used for demonstrating
• Files starts with rpi*** encapsulate low-level hardwares

Prerequisite

If you are familiar with C, you are good to go.

Note

• Format SD card to FAT

• Copy bootcode.bin and start.elf to SD card (you can find them under external_resources folder)

• Cross-compiler can be found under external_resources/arm-gcc/. Add PATH to gcc-arm-*/bin

• If everything is correct, simply type make in the main source folder will generate kernel7.img. Copy this image to SD card.

• make clean as needed

• I referred to several materials and online codes when I was doing this project. I could miss references and credits for these sources.