LPT port connection

shalom

I'm trying to proram the BS1 on a laptop that doesn't have a serial port, and so far I've been unsuccessful.
Right now I just have the BS1 connected directly to the parallel port and I'm using the DOS version. It just tells me the hardware is disconnected. I've got power connected to the stamp. I put LEDs from PC0 and PC1 to gnd, but I get no activity when I try to run the program. I have a Toshiba with Win XP. I've tried searching through the archives, but I havent found anything that helps much. Any ideas?

John

Jon Williams

You may not be able to do this; the DOS version needs COMPLETE control of the printer port for bit-banging the serial stream to the BS1, and under XP this is not likely to happen. You might try a DOS box, or creating a DOS boot disk.

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Jon Williams
Applications Engineer, Parallax
Dallas, TX· USA

shalom

Thanks, I tried the boot disk, but it wouldn't let me access the c: drive, so I put the stamp.exe and the source code on the disk and ran from it. What I found was that the LED across the PC0 (LPT pin 11) and gnd was dimly lit and slowly, constantly blinked. PC1 (LPT pin 2) was more brightly lit and was ON when the program was NOT searching for the device, but would turn off and back on when I did Alt-R. Any more thoughts? I realize this is kind of a long shot, but I thought I would give it a try before going for another comp.

John

Jon Williams

Remove the LEDs, you may be affecting the download to the BS1. What's happening is that 4800 baud serial is being bit-banged on the port at TTL levels (hence the use of the printer port).

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Jon Williams
Applications Engineer, Parallax
Dallas, TX· USA

shalom

That should have been a no-brainer...
Now I get an error message that says "EEPROM verification failed." I tried disconnecting/reconnecting the power, but it didnt make a difference. I'll take any more suggestions, but thanks for you help.

John