Update README.md

README.md

 # scalplinux-toolchain
 
-Scalp Linux Toolchain
\ No newline at end of file
+## Howto download Scalp Linux Toolchain
+
+```bash
+$ cd /opt
+$ sudo git clone https://gitedu.hesge.ch/soma/scalplinux-toolchain.git
+$ echo -n "export SCALPLINUX_TOOLCHAIN=\"/opt/scalplinux-toolchain/board/scalp/cross/bin/\"" >> ~/.bashrc
+$ echo -n "export PATH=\${PATH}:\${SCALPLINUX_TOOLCHAIN}"
+```
+
+## Howto compile a new program for the Scalp target with a Makefile
+
+```bash
+$ export CROSS_COMPILE=arm-scalp-linux-gnueabihf-
+$ export ARCH=arm
+$ make
+```
+
+Or ...
+
+```bash
+$ CROSS_COMPILE=arm-scalp-linux-gnueabihf- ARCH=arm make
+```
+
+## Howto compile a new program for the Scalp target without a Makefile
+
+```bash
+$ arm-scalp-linux-gnueabihf-gcc -o <BIN_NAME> <SOURCE_NAME>.c
+```