[Avrora] USART0, UDRE interrupt

[Richard Barrington]

Ben L. Titzer wrote:

>
> There may be a problem with the USART implementation; it should handle 
> the posting of interrupts on its own, and your platform class need not 
> implement this behavior on its own. Which microcontroller model does 
> your platform use?
>
Hmm, I thought that's what should happen. My platform uses 
avrora.sim.mcu.ATMega128

> I usually test against code that I think does not rely on the 
> interrupts to determine when to send the next byte, so I think I may 
> not have exercised this case. I have a lot on my hands right now, but 
> if you want to take a look at the relevant code, you will find it in 
> avrora.sim.mcu.USART.
>
I'll have a look. :-)

> It may also be a bug with the interrupt mapping numbers (i.e. 
> simulator posts the wrong interrupt number which is masked out by your 
> program). You can check this with a probe or watch through the 
> State.getInterruptTable() method, which has methods to check which 
> interrupts are posted, enabled, pending, etc.
>
> Hope this helps,
> -B

Thanks Ben, I appreciate the pointers.

Rich.