Problems with lpt1 lockup

Development Boards MicroMod
1

Hello to all,

I have just gone through the first part of the Sparkfun tutorials (brilliant) on micro programming and have got the light flashing. Yay!

My problem is this: after I download the hex file (hello.world) to the micro, the lpt1 port locks up. I say this because I see the status of the port pins on a breakout box and they go from a ‘normal’ state of high at pins 1,4,10,11,13,14 (before programming) to all low after the programming. After the first successful download, I cannot download anything else. AVRdude says that “the device is not recognized”.

I have shut down the program, disconnected the cables from the port and power cycled the micro but nothing remedies the problem. The only thing that seems to work is power cycling the computer. Then lpt1 resets to normal state.

Does anyone have any ideas on how to ‘reset’ the lpt1 port without having to reset my computer? Is it a problem with the computer, the program (WinAVR) or the code?

Thanks for your time and help,

Pike.

2

do you have a schematic for the programmer you are using? Which avr are you using?

try some different software.

search for avreal, fbprg. I would try the dos versions to be sure that the port is not at fault.

3

I am going through the Sparkfun tutorial (embedded electronics) using their recommendations. I am using the AVR-PG2 programmer, the Atmega 168 chip and the AVR STK parallel port programmer.

Here is the schematic for the programmer:

http://www.olimex.com/dev/images/avr-pg2b-sch.gif

4

try this program:

http://www.ln.com.ua/~real/avreal/index_e.html

it will work with your programmer cable.

Use the dos version, (make a dos boot disk and use it in straight dos)

I found it always works no matter what PC I use.

This way you can rule out if there is a parallel port or other hardware problem.

Good Luck