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 >
AVRISP
Started by ●October 8, 2004
Reply by ●October 9, 20042004-10-09
Reply by ●October 9, 20042004-10-09
Hopkins wrote:> 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.Try reading the data sheet ? In there, you will see +12V is applied to /RST. -jg
Reply by ●October 10, 20042004-10-10
On Sun, 10 Oct 2004 09:38:30 +1300, "Hopkins" <rdhopkins@ihug.co.nz> wrote:>Thanks again Alan, > >Who are your prefered suppliers of Atmel / AVR chips? >Well I am using SMD parts (AtMega16, AtMega32) so I buy them through distributors in quantities as I need them. I use a couple of DIP chips of each type for prototyping and just keep reprogramming them as required. Dontronics have a range of Atmel parts at reasonable prices, have a look at : http://www.dontronics.com/cat_hard_micro_avr.html With the oscillator you also have to remember that the fusebits have to be set correctly for whatever crystal you are using otherwise the internal oscillator will not work right or not at all. If you somehow select "external oscillator" then you will have to supply an external clock to recover. I built a separate oscillator/divider box as it was more convenient for me (I build different proto boards as I require as well as having my "standard" board). If you build your oscillator on your development board just make sure you put some means on there for extracting the closk for another board when you need it. ICs are normally shipped with the internal RC oscillator selected (1MHz). Alan ++++++++++++++++++++++++++++++++++++++++++ Jenal Communications Manufacturers and Suppliers of HF Selcall P O Box 1108, Morley, WA, 6943 Tel: +61 8 9370 5533 Fax +61 8 9467 6146 Web Site: http://www.jenal.com e-mail: http://www.jenal.com/?p=1 ++++++++++++++++++++++++++++++++++++++++++
Reply by ●October 10, 20042004-10-10
"Hopkins" <rdhopkins@ihug.co.nz> wrote in message news:ck9kh4$abl$1@lust.ihug.co.nz...> Thanks Anton. > > So what does a parrallel programer do that allows it to recover the > situation, ie can I not rig up somthing to over come the problem? > >> >> You might also have programmed the ATMega8's reset pin to be a GPIO >> pin. Once you have done this, then you have to use a parallel >> programmer to program the chip again. >> >> Regards >> Anton ErasmusJust make a parallel programmer or buy one. http://www.dontronics.com/auto.html#avr http://www.dontronics.com/atmel.html Also have a browse at http://www.avrfreaks.net/ free to join, look under academy schematics (just make sure you get the right circuits) http://www.lancos.com/prog.html http://www.myplace.nu/avr/yaap/ avrdude http://savannah.nongnu.org/projects/avrdude/ http://www.bsdhome.com/avrdude/ lots of others http://www.google.com/search?num=50&hl=en&lr=&safe=off&q=avr+programmer+circuits&btnG=Search http://www.serasidis.gr/
Reply by ●October 10, 20042004-10-10
On Sun, 10 Oct 2004 16:08:04 +1000, "Alex Gibson" <me@privacy.net> wrote:> >"Hopkins" <rdhopkins@ihug.co.nz> wrote in message >news:ck9kh4$abl$1@lust.ihug.co.nz... >> Thanks Anton. >> >> So what does a parrallel programer do that allows it to recover the >> situation, ie can I not rig up somthing to over come the problem? >> >>> >>> You might also have programmed the ATMega8's reset pin to be a GPIO >>> pin. Once you have done this, then you have to use a parallel >>> programmer to program the chip again. >>> >>> Regards >>> Anton Erasmus > >Just make a parallel programmer or buy one. >There seems to be confusion about what an AVR parallel programmer is. Many programmers refered to as a parallel programmer, is a programmer driven from a PC's parallel port. From the point of view of the AVR it is a serial programmer. I cannot recall having seen any programmers available that is a parallel programmer from the AVR's point of view. Regards Anton Erasmus
Reply by ●October 10, 20042004-10-10
On Sun, 10 Oct 2004 10:26:32 +0200, Anton Erasmus <nobody@spam.prevent.net> wrote:>I cannot recall having seen any programmers available that is a >parallel programmer from the AVR's point of view.STK500 is the only one that I know of. -- Mikael Ejberg Pedersen
Reply by ●October 10, 20042004-10-10
Anton Erasmus wrote:> On Sun, 10 Oct 2004 16:08:04 +1000, "Alex Gibson" <me@privacy.net> > wrote: > > >>"Hopkins" <rdhopkins@ihug.co.nz> wrote in message >>news:ck9kh4$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 ●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 ●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 ●October 12, 20042004-10-12
