7 Apr
2012
7 Apr
'12
8:47 a.m.
On Apr 7, 2012, at 10:10, S?ren Gust <sgust at ithh.informationstheater.de> wrote:
On Fri, Apr 06, 2012 at 04:41:47PM -0300, Alexandre
Souza - Listas wrote:
You may have better luck with the XMEGA AVR series (I'm using an ATXMEGA32A4 in a
current project). They've restructured the I/O and interrupts and added DMA and a
curious "event" system which can take a lot of the work off the processor.
Definitely worth considering.
Failing that, you can get low-power ARM Cortex-M3s for about the same price now.
- Dave
I still believe I can do that with a fast
microcontroller. As
soon as I can put my dirty hands into one I'll jack it up to the
logic analyser and play with that.
I tried that about 2 years ago using an ATmega644. It nearly worked, but
when the C64 switched from one keyboard row to the next the ATmega644
generated several pin change interrupts. This took too long to process
and the C64 got the wrong answer. Maybe one day I will look into faster
processors but the ones I know about are quite slow at I/O. The timing
of the NMI routine (for checking RUN/STOP when RESTORE is pressed) is
even tighter than the normal IRQ.