Bruce Partridge wrote:
>> This doesn't make any sense.  You are only updating the data every 4
>> seconds, and only processing it every 5-15 seconds.  What's the big
>> deal holding off interrupts while the main routine makes a copy of
>> the arrays? The interrupt won't get lost, just delayed 66mS
>> according to your figures. Since you've got 4 seconds to do 150mS of
>> processing, this doesn't sound like a problem.
>
> Its a problem because I want to update the display three times per
> second. I have other things going on in the isr.  It reads sensors,
> fires a solenoid,  shows several different displays.  Some of the
> displays have to flash to show error conditions.  Its not an
> impossible solution, but its not great either.

This still doesn't make sense.  You haven't mentioned anything that sounds
like it can't wait 66mS.  Besides, 66mS seems waaaaaay too long to copy 128
bytes.  Disable interrupts around just the copy operation, then do all the
remaining processing with interrupts enabled.  Where did you get the 66mS
figure from?


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