Parallella Community

Yep, I'm pretty confident that I understand it now. Thanks everyone!

Looking at the figure 14 on page 59, I'm not sure if the wording of the box 'If nesting, Save Context & Execute "GIE" ' is correct. Should it be two boxes, one that says 'Save Context' and the other 'If nesting, Execute "GIE" '? (If so the Restore box needs splitting too.)

Would it be helpful to give some text about save context? e.g. Any registers that are changed which can include Status register, general-purpose registers and possibly Config register.

On page 62 the use of C to program interrupt handlers is recommended. This does have a drawback in that the wrapper for the handler spends a lot of time saving and restoring registers as it has no idea which ones the handler will actually use. (These are the Caller saved ones in the procedure call standard.) An assembler routine only needs to save and restore the ones it uses.

Tim

Tim,
I agree that the diagram should be fixed,it should make it into the next revision of the manual.

I will also remove the recommendation about writing the ISR in C. Assembly really isn't that scary and it can be much faster..

Andreas