[avrdude-dev] Parallel port doesn't keep programmed states

[idefixx]

Hi guys!
As I can see you are all a very fast and flexible group! congratulations! But 
before you make your next release, I want to call your attention to another 
problem that I have encountered.

Every time after rebooting my windows XP system (running on Intel Celeron 
500MHz, 256MB RAM) I have got a problem programming my microcontroller with 
AVRdude using the parallel port dongle. When I start the programming, the first 
few seconds everything works fine. But after having written to the AVR for some 
seconds, AVRdude reports a program fail for every single byte. Also, if I 
repeat programming - again after a certain time (not the same time) AVRdude 
reports " ***failed; ". As often I repeat, AVRdude never can manage to program 
the AVR fully.
What I do then, to get it work, is to read out the AVR flash memory. After this 
I again try to program the AVR and - oh wonder - then it works without a 
problem. This problem just appears after rebooting my system.

I now did a little test using the ppiwin.c file only. I modified it by 
inserting a main() function so that I can run it by itself in order to control 
the parallel output pins. Here the same thing happens again. After some seconds 
the parallel port pins automatically change their states. I couldn't find out 
so far, why. This seems to me is the same problem that appears when I use 
AVRdude, because here after performing an AVR read out suddenly this automatic 
change of port pin states doesn't appear anymore until the next reboot.

Does someone have a clue, what could be the problem?
Sorry for coming up with new problems all the time   ;-)
/idefixx