Reply by Dorsai October 14, 20042004-10-14
Rich Webb <bbew.ar@mapson.nozirev.ten> banged on the keyboard until
producing news:fecrm0pdv6uccf219674h7477f455qbkm7@4ax.com: 

> On Wed, 13 Oct 2004 07:01:11 -0500, Dorsai <dorsai@mail.com> wrote: > >>Rich Webb <bbew.ar@mapson.nozirev.ten> banged on the keyboard until >>producing news:9btom0pq3denjo9vit30l28en8j1qvj6cs@4ax.com: >> >> >>> Having a few JTAG dongles sitting around here (TI MSP430, Cypress >>> something (clear blue plastic box), a Xilinx Parallel 3, and an >>> Altera ByteBlasterMV clone (dang, these things do accumulate)) does >>> anyone know if the Atmel JTAG software can be fooled into using one >>> of the others? >>> >> >>JTAG is _supposed_ to be JTAG. Compare the pinouts of the various >>devices you have, and that should answer your question. > > On the JTAG side, you are correct of course. However, different > parallel port pins and logic can be used to drive/receive the JTAG > signals. >
That's what I'm saying: take a look at the outputs of the various dongles and see if any match up. -- * * * * * * * * * * * * * * * * * Dorsai - Author of Erotic Fiction http://www.asstr.org/~Dorsai * * * * * * * * * * * * * * * * * "Economics is extremely useful as a form of employment for economists." -- John Kenneth Galbraith
Reply by Rich Webb October 13, 20042004-10-13
On Wed, 13 Oct 2004 07:01:11 -0500, Dorsai <dorsai@mail.com> wrote:

>Rich Webb <bbew.ar@mapson.nozirev.ten> banged on the keyboard until >producing news:9btom0pq3denjo9vit30l28en8j1qvj6cs@4ax.com: > > >> Having a few JTAG dongles sitting around here (TI MSP430, Cypress >> something (clear blue plastic box), a Xilinx Parallel 3, and an Altera >> ByteBlasterMV clone (dang, these things do accumulate)) does anyone >> know if the Atmel JTAG software can be fooled into using one of the >> others? >> > >JTAG is _supposed_ to be JTAG. Compare the pinouts of the various >devices you have, and that should answer your question.
On the JTAG side, you are correct of course. However, different parallel port pins and logic can be used to drive/receive the JTAG signals. -- Rich Webb Norfolk, VA
Reply by Dorsai October 13, 20042004-10-13
Rich Webb <bbew.ar@mapson.nozirev.ten> banged on the keyboard until
producing news:9btom0pq3denjo9vit30l28en8j1qvj6cs@4ax.com: 


> Having a few JTAG dongles sitting around here (TI MSP430, Cypress > something (clear blue plastic box), a Xilinx Parallel 3, and an Altera > ByteBlasterMV clone (dang, these things do accumulate)) does anyone > know if the Atmel JTAG software can be fooled into using one of the > others? >
JTAG is _supposed_ to be JTAG. Compare the pinouts of the various devices you have, and that should answer your question. -- * * * * * * * * * * * * * * * * * Dorsai - Author of Erotic Fiction http://www.asstr.org/~Dorsai * * * * * * * * * * * * * * * * * Giving power and money to Government is like giving whiskey and car keys to teenage boys - P.J. O'Rourke
Reply by Rich Webb October 12, 20042004-10-12
On Tue, 12 Oct 2004 22:26:43 +0200, Anton Erasmus
<nobody@spam.prevent.net> wrote:

>On Sun, 10 Oct 2004 10:46:01 +0200, Mikael Ejberg Pedersen ><mikael@ejberg.NO_SPAM_HERE.dk> wrote: > >>On Sun, 10 Oct 2004 10:26:32 +0200, Anton Erasmus >><nobody@spam.prevent.net> wrote: >> >>>I cannot recall having seen any programmers available that is a >>>parallel programmer from the AVR's point of view. >> >>STK500 is the only one that I know of. > >Is the STK500 not a JTAG programmer ?
No, it uses the chip's SPI ports for programming. Take a look at, for example, the data sheet on the ATmega64 that supports both JTAG and SPI programming. Having a few JTAG dongles sitting around here (TI MSP430, Cypress something (clear blue plastic box), a Xilinx Parallel 3, and an Altera ByteBlasterMV clone (dang, these things do accumulate)) does anyone know if the Atmel JTAG software can be fooled into using one of the others? -- Rich Webb Norfolk, VA
Reply by Mikael Ejberg Pedersen October 12, 20042004-10-12
On Tue, 12 Oct 2004 22:26:43 +0200, Anton Erasmus
<nobody@spam.prevent.net> wrote:

>Is the STK500 not a JTAG programmer ?
No. STK500 is a development kit capable of serial AND parallel programming nearly every AVR type. But it doesn't do JTAG. -- Mikael Ejberg Pedersen
Reply by Anton Erasmus October 12, 20042004-10-12
On Sun, 10 Oct 2004 10:46:01 +0200, Mikael Ejberg Pedersen
<mikael@ejberg.NO_SPAM_HERE.dk> wrote:

>On Sun, 10 Oct 2004 10:26:32 +0200, Anton Erasmus ><nobody@spam.prevent.net> wrote: > >>I cannot recall having seen any programmers available that is a >>parallel programmer from the AVR's point of view. > >STK500 is the only one that I know of.
Is the STK500 not a JTAG programmer ?
Reply by Chris Alexander October 10, 20042004-10-10
Hi - I had exactly this problem with a Mega8.  

The suggestion that you accidentally ticked the external oscillator
fuse was, in fact, what the problem was (for me).  I was able to take
a 2 mhz TTL oscillator "can" and wire it to XTAL1 and reprogram the
fuses.  I have not had any problems since - but now I set the fuses
only once to my desired settings *and never program them again*.  Now
I only update Flash in the programming window.

This is a very common accident - I found help very quickly over the
weekend at the AVR Freaks forums.  Take a look at
http://www.avrfreaks.net/

Cheers,
Chris


"Hopkins" <rdhopkins@ihug.co.nz> wrote in message news:<ck6nit$oma$1@lust.ihug.co.nz>...
> I have the AVRISP and when programming the ATMega 8 chip I have 2 chips out > of four that have locked up when been reprogrammed to the point the AVRISP > programmer complains it can not enter programming mode. > > I asked ATMEL about the problem and they just said that I must have the > wrong fuse bits set! > > IMHO why the hell should a product produced by a comercial company have a > bug that allows you to corrupt the chip you are programming to the point > that you can not even reset the fuse bits anymore. > > Have read that this situation can be rescued with a parrallel programmaer, > is there a way I can rig somthing up to reset the fuse bits other than > buying another programmer? > > Thanks in advance Roy.
Reply by Jim Granville October 10, 20042004-10-10
Anton Erasmus wrote:
> On Sun, 10 Oct 2004 16:08:04 +1000, "Alex Gibson" <me@privacy.net> > wrote: > > >>"Hopkins" <rdhopkins@ihug.co.nz> wrote in message >>news:ck9kh4$abl$1@lust.ihug.co.nz... >> >>>Thanks Anton. >>> >>>So what does a parrallel programer do that allows it to recover the >>>situation, ie can I not rig up somthing to over come the problem? >>> >>> >>>>You might also have programmed the ATMega8's reset pin to be a GPIO >>>>pin. Once you have done this, then you have to use a parallel >>>>programmer to program the chip again. >>>> >>>>Regards >>>> Anton Erasmus >> >>Just make a parallel programmer or buy one. >> > > > There seems to be confusion about what an AVR parallel programmer is. > Many programmers refered to as a parallel programmer, is a programmer > driven from a PC's parallel port. From the point of view of the AVR it > is a serial programmer. I cannot recall having seen any programmers > available that is a parallel programmer from the AVR's point of view.
Looking at the datasheet on the ATmega16, for example, you will see pages 261..288 cover THREE FLASH/EE programming modes Parallel Programming : This applies 12V to RESET, and that over-rules any LOCK or Fuse bits, and allows programming. Appx 18 singal pins need to be connected for parallel Program Mode. Serial SPI Programming : This does not use high voltage, but can be excluded via security options. This mode needs appx 5 signal pins connected. "Depending on CKSEL Fuses, a valid clock must be present." JTAG serial Programming: It says " Programming through the JTAG interface requires control of the four JTAG specific pins: TCK, TMS, TDI and TDO. Control of the reset and clock pins is not required. To be able to use the JTAG interface, the JTAGEN Fuse must be programmed. " Commercial Universal programmers tend to be Parallel, because that is fastest, and also has no 'blind spots', or one-way-streets :) Some other uC use OTP fuses for ISP - that is a real one way path. Blow that, and the chip becomes OTP. Usefull for security features, but not so nice to 'oops' in the development LAB :) -jg
Reply by Mikael Ejberg Pedersen October 10, 20042004-10-10
On Sun, 10 Oct 2004 10:26:32 +0200, Anton Erasmus
<nobody@spam.prevent.net> wrote:

>I cannot recall having seen any programmers available that is a >parallel programmer from the AVR's point of view.
STK500 is the only one that I know of. -- Mikael Ejberg Pedersen
Reply by Anton Erasmus October 10, 20042004-10-10
On Sun, 10 Oct 2004 16:08:04 +1000, "Alex Gibson" <me@privacy.net>
wrote:

> >"Hopkins" <rdhopkins@ihug.co.nz> wrote in message >news:ck9kh4$abl$1@lust.ihug.co.nz... >> Thanks Anton. >> >> So what does a parrallel programer do that allows it to recover the >> situation, ie can I not rig up somthing to over come the problem? >> >>> >>> You might also have programmed the ATMega8's reset pin to be a GPIO >>> pin. Once you have done this, then you have to use a parallel >>> programmer to program the chip again. >>> >>> Regards >>> Anton Erasmus > >Just make a parallel programmer or buy one. >
There seems to be confusion about what an AVR parallel programmer is. Many programmers refered to as a parallel programmer, is a programmer driven from a PC's parallel port. From the point of view of the AVR it is a serial programmer. I cannot recall having seen any programmers available that is a parallel programmer from the AVR's point of view. Regards Anton Erasmus