Hello, Simplex and Reinhard: Have you heard about CooCox and CoX?I found CooCox have write a library that looks like a standard interface and library, it is CoX library.This library include the PeripheralsInterface Standard.They have support Peripherals such as GPIO, ADC, UART, etc.And there are CoX libraries for STM32F10x series and Freescale M0+ series. They also have the plan for NXP and TI. They said that " drivers based on CoX can be ported to other MCU easily."I haven't use CoX before, but it seems to be very easy to use if I want to learn how to start with ARM. What do you think about that?