I am really having a hard time getting ATmega328s to survive parallel port programming. I bought a couple a year ago and using the barest ppp, MOSI, SCLK and MISO tied directly to the parallel port thru 1k resistors, and they both failed with MISO, the chip output, going bad. I went back to PICs, I've NEVER had one fail even using the simplest of Tait type programmers on the parallel port.
Well I decided to try Atmel and Arduino again and built the PPPD programmer from this web site http://www.aplomb.nl/TechStuff/PPPD/PPPD English.html
Which uses a 74HC244 buffer (I used an LS device since I have them and the 328 is spec'ed to supply up to 40 ma and LS TTL draws less than 10ma and the LED/1k resistor draws just over 3ma on pin 13).
Since I am nearly broke, my job went to China, I bought three ATmega328s since three chips were cheaper than any one Arduino board.
I first just used avr-gcc to create a simple output pin square wave and set the fuses for low power oscillator and 16 Mhz crystal, 22 pf caps, etc. It worked fine. The I tried running the Blink example sketch and never got it to run. This is what I was trying to trouble shoot and the problem is posted in the Installation and Troubleshooting forum.
But, then avdude complained about not finding a chip and sure enough the oscilloscope showed no activity on the MISO line it just stays high. If you disconnect the MISO line from the programmer it drops to gnd and when avrdude is executed you do see pulses as it tries to reply, but they are less then 250mv in amplitude.
fwiw, I haven't killed an ATmega yet, despite quite a bit of ArduinoISP programming of bootloaders and such...
Have you spent enough on your cheap programming setup to think maybe you should have bought one of the $10 USBASP programmers, or a $20 USBtinyISP yet? I mean, I'm as frugal as frugal can be, but the price of "real" programmers has been going down, while the difficulties in using a parallel port have been getting worse...
westfw:
fwiw, I haven't killed an ATmega yet, despite quite a bit of ArduinoISP programming of bootloaders and such...
Ditto, although my experience is limited to the USBtinyISP, it's worked great. I did accidentally power an ATmega328 project on 9V the other day, just for a couple seconds, but it's still going...
Now that we've sufficiently tempted the "chump gods" I suppose we'll be frying things left and right
westfw:
I mean, I'm as frugal as frugal can be, but the price of "real" programmers has been going down, while the difficulties in using a parallel port have been getting worse...
Ditto. The cost is so low compared to the potential trouble one can get into. However, I would stay away from the Adafruit unit until they resolve their inability to program any Atmel with more than 64kB of memory. There are other choices out there at very low cost, CrossRoads mentioned a programmer to me (that I have since forgotten) that was a design based on the AVR ISP MKII which sold for less than $20 and which was compatible with 'larger' Atmel chips. If I hadn't already bought my programmer from Atmel, I would have jumped on that unit instead.
westfw:
fwiw, I haven't killed an ATmega yet, despite quite a bit of ArduinoISP programming of bootloaders and such...
Have you spent enough on your cheap programming setup to think maybe you should have bought one of the $10 USBASP programmers, or a $20 USBtinyISP yet? I mean, I'm as frugal as frugal can be, but the price of "real" programmers has been going down, while the difficulties in using a parallel port have been getting worse...
And it only features a 10 pin head assy as best as I can tell. Maybe the conversion over to a 6-pin head is easy. But I'd look for a 6-pin unit. Plus, being told that the unit in question will be randomly selected from among two (when it is unclear what unit does what) is not exactly heart-warming either.
Yeah; it's a little questionable which firmware those extra-cheap programmers will end up containing. In theory, they should be re-progammable with something better...
after i build my own version of usbasp (programmed it with arduino) i bought a cheap clone from ebay because it was so cheap and i paid 6$
as soon as i got it plugged it into my laptop everything was good unit was running, problems appeared after i flashed the last version of the usbasp firmware - the upgrade made the programmer unusable (wasn't anymore recognized by the OS and wasn't listed a usb device)
since the programmer didn't come with a datasheet or a schematic i can't think what could have gone wrong - only thing that i can think would be that the pin were changed and they wouldn't match usbasp schematic/firmware
and my usbasp can burn bootloader with no problem ive burned on atmega8,168,328 without any problems
Unless you are programming a bunch of chips you aught to look into using your Arduino as an ISP. the wiring is simple and it is easy to use, I find it painless and built a small board that I connect up to ma Arduino and program my chips. I have been programming ATTiny2313 and ATMega328 chips with no problem.
