Interrupts occurrence

Joel Sherrill joel.sherrill at
Sat Feb 23 01:04:29 UTC 2002

Angelo Fraietta wrote:
> I worked it out. I did not have the interrupt pin held high for long
> enough. I am now generating and decoding interrupts every 1 Ms.

I am glad you worked it out.  I would expect that you can sustain
a fairly high interrupt rate but it always depends on how much
processing is required per interrupt in the ISR and what 
that implies for task processing.  Sure you can do a LOT of 
interrupts that clear a bit and return but useful work is another
matter.  For example, sustaining a high RX rate on a UART is
often more than a CPU can do.


> Angelo Fraietta wrote:
> > At what speed can I have interrupts happening in the pc386 bsp running
> > at 16 MHz. I am generating an interrupt with an external
> > microcontroller -- currently every 30 Ms (I was hoping to make it
> > possible every 1 Ms) -- however, the 386 is missing some of the
> > interrupts.  I am attempting to transfer data between the
> > microcontroller an the 386 by using a 16 Bit device driver and using
> > interrupts to synchronize the two processors. Should I be trying to
> > use DMA for data transfer rates of this speed?
> >
> --
> Angelo Fraietta
> PO Box 859
> Hamilton NSW 2303
> Home Page
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