Re: [avrdude-dev] ppi speed-tuning ;-)

[Theodore A. Roth]

On Wed, 19 Nov 2003, Brian Dean wrote:

> On Wed, Nov 19, 2003 at 02:24:21PM +0100, Jan-Hinnerk Reichert wrote:
> 
> > as promised here is a patch that should speed up the SPI 
> > communication. The idea is quite simple:
> 
> Just to follow up - I've tested Ted's and your avr.c patch to fix the
> min_delay logic and repeated Ted's results.  My programming time for
> an 8515 went from 2m36s down to 24.41 seconds - nearly identical
> results as he got.
> 
> With this patch also applied, that time went from 24.41 seconds down
> to 20.84 seconds, so that gained us another 15% or so.

Just tested the latest patch with 2 8515 devices.

               w/ patch    w/o patch
  Part #1      21.042s     24.923s
  Part #2      22.306s     24.853s

Brian, were you uisng the test.srec file I posted last night?

> 
> The first patch was the biggie, though.  It's not often we get to see
> a 6 times speed-up!
> 
> And now the big test, how fast is the STK500 for this same file /
> part?  The result was 20.84 seconds!  We are now equal to the STK500
> which is a very nice programmer and the fastest one I've used, until
> now.

Just tried the stk500 with the same 2 8515 devices and got these 
numbers:

  Part #1   20.568s
  Part #2   22.392s

Looks like parity to me.

Ted Roth