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Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?
From: |
Galen Seitz |
Subject: |
Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems? |
Date: |
Fri, 25 Jun 2004 13:01:39 -0700 |
Bob Paddock <address@hidden> wrote:
>
>
> >> mega48. I ended up patching avrdude to allow the stk500 spi clock to be
> >> set to a lower speed.
> >
> > And that patch is still in the patch manager here:
> > <http://savannah.nongnu.org/patch/?func=detailitem&item_id=3136>
>
> par.c
> /*
> * transmit and receive a byte of data to/from the AVR device
> */
> ... /*
> * Due to the delay introduced by "IN" and "OUT"-commands,
> * T is greater than 1us (more like 2us) on x86-architectures.
> * So programming works safely down to 1MHz target clock.
> */
>
> That 1 MHz is probably the problem. So I need to move the Galen's
> stk500 patch into par.c to get it down to 250 kHz as well, it would
> seem? The patch indicates it is "STK500 only", so it needs updated to
> not be STK500 specific also.
>
I looked at the datasheet for the tiny2313. The default clock is the
calibrated 4 MHz osc with the CKDIV8 active, giving a frequency of
500 kHz. The maximum SPI clock is CLK/4, so the programmer SPI clock
needs to be <= 125 kHz.
The stk500 has a command to control the SPI clock frequency, that's
why my patch is stk500 specific. Assuming the pony is bit-banged,
my patch won't be useful to you. A call to usleep() is what I would
use under Linux, but I don't know if this is available across all
the platforms that avrdude supports.
galen
- [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Bob Paddock, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, E. Weddington, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Bob Paddock, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Galen Seitz, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, E. Weddington, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Bob Paddock, 2004/06/25
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?,
Galen Seitz <=
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Jan-Hinnerk Reichert, 2004/06/27
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Bob Paddock, 2004/06/28
- Re: [avrdude-dev] ATtiny2313 and pony-stk200 problems?, Jan-Hinnerk Reichert, 2004/06/29