Are 4000 interrupts per second a problem for AVR?

"David Brown" <david@westcontrol.removethisbit.com> skrev i meddelandet 
news:4417c7b5$1@news.wineasy.se...
> Ulf Samuelsson wrote:
>>> I've done a 2kHz piezo using a 4MHz '05 (1MHz bus rate) (interrupt
>>> every 250usec), with enough time left over to do 32-bit PID control,
>>> 15-bit slope ADC and scan displays/keyboard, so I don't think you'll
>>> have any problems with an 8Mhz AVR 'less'n you do something silly like
>>> write the ISR in C.
>>>
>>
>> My record for real time response is 250,000 context switches per seconds 
>> on an HPC16083
>> 32 tasks, each running 4 us (including the context switch)
>>
>> Not too bad for a CPU with just a few MIPS.
>
> The HPC has more than just a few MIPs - can't they run at up to 40 MHz?

Only the HPC46100, the others were limited to 16-20 Mhz,
and it was an accumulator based architecture with a few address register.

>  (Our HPC apps never used more than 10 MHz.)  About 15 years ago, they 
> were one of the fastest microcontrollers available.  Still, at 250,000 
> context switches a second, there can't have been much left cpu time left 
> after the context switch overhead?

Nope, the memory to memory address mode helped a lot.

>
>> When there is a will, there is a way.



-- 
Best Regards,
Ulf Samuelsson
This is intended to be my personal opinion which may,
or may bot be shared by my employer Atmel Nordic AB