Does anyone know of an Idiot's Guide to this topic? In particular, how does a processor with no special I/O instructions issue a request, e.g. to a serial output device to output "Hello, World"? And how does Memory-Mapped I/O work in detail? Where is the Memory Map stored? What are the actual contents of Device Memory? And where do AMBA/AXI (or ACE) fit in? (I did say it had to be an Idiot's Guide!)
I like the idea very much.
We have quite a few employees, like myself, who have been STEM ambassadors. I have usually done drawings on a whiteboard, showing the path the information is following.
When you say a serial output device, do you consider that the device has a module dedicated to that (UART/RS232 type) or should the explanation just use a normal I/O to emulate what is usually done in a dedicated module?
Here is on the right an interestingly simple diagram which locates the on-chip bus. You can click on the image to see it bigger.
Chris, would you happen to have written (or know of) such document about processor basics within ARM?
The simpler the example, the better, Alban; if that means normal I/O, fine. Although, UART is in itself an interesting example, having Synchronous versus Asynchronous versions (the latter being akin to what we used to call "Start/Stop Comms". And, unfortunately, I didn't receive your diagram.
View all questions in Cortex-A / A-Profile forum