Hi Roland

On Friday 09 March 2007 15:17, roland Tollenaar wrote:
> If it is also not possible to optimize the code further then IMHO  we
> are looking at a fundamental hardware constraint.

I think it was Sebastian that said there are 14 reads and one write per 
interrupt - If this is the case, then looking at the Peak parport dongle 
driver, I see eight IO instructions per read and six per write. A total of 
118 inb(). outb() calls - Not a particulaly large amount, however, a standard 
parallel port takes one to two microseconds to service each call, so 200uSec 
for the interrupt handler would quite reasonable..

 One way to reduce the time spent servicing IO instructions would be to switch 
to a PCI based parport card (not sure if it would be compatable with the 
driver & dongle).. Or alternatively use a PCI CANbus card.


Regards, Paul.


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