Testing RAM may be a waste of time guys....But I do believe that with the modern parts with onboard flash that is typically programmed in circuit that a program code validation signature is a good idea. Flash memory programming is not a digital process and as such there is always the possibility of marginally programmed bits. A FLASH validation is a good idea. It is best to make this code small, in assembler, and part of the startup code.

Now YES there are those that will argue that if FLASH is bad than how can the program execute properly. So be it....but is also good to know that the whole program image is GOOD to some fairly high statistical possibility. Program validation codes can also be a useful measure to ensure that the proper version of software is loaded into the product, especially of the validation code can be displayed on a startup screen that shows the software info.

Michael Karas