chARM is a Realtime Operating System developed from scratch that runs on ARM platform. chARM implements Earliest Deadline First (EDF) scheduling algorithm. Its periodic threading model allows creating tasks with arbitrary period, budget, deadline and phase having granularity and accuracy of few microseconds. chARM currently runs on Mini210s development board which has Samsung S5PV210 SOC with Cortex-A8 core operating at 1GHz. It also runs on TQ2440 development board which has Samsung S3C2440 SOC. Each application in chARM is compiled and built independently from the kernel. A ramdisk File System image is prepared with all applications, data and loaded by the kernel when it starts. The main goal of this OS is to be able to use it in safety critical hard realtime applications. This repository is self contained and has all the tools and scripts necessary to build, run this OS and also debug using GDB. Each application and the kernel has its own address space and are protected from each other.