|Re: HP-IL I/F Card on a New(er) PC - Part II|
Message #15 Posted by Gerry Schultz on 5 July 2009, 10:50 p.m.,
in response to message #14 by Egan Ford
Hello and thank you for your responses.
I've been doing research on this issue this afternoon and have made some progress but also have some questions. First, I found that I was using the wrong version of the 82973A's Owner's Manual. My card is a revision A, which is not covered in Edition 4 of the Owner's Manual, dated May 1987. I ended up using Edition 3, dated November 1985, and it covers revision A and the I/O range address switches are identified properly. Edition 4 of the Owner's manual covers revisions after A and those address switches are labeled differently.
Second, I've been looking at my card it is set to use IRQ 7 which isn't talked about anywhere in the Owner's manual. It can be set via jumpers to any IRQ between 2 and 7. Is an interupt required for this card to work properly? If it doesn't this might help resolve the conflicts with this PC motherboard.
I found another HP-IL I/F card pictured on that unmentionable site today and the picture of that I/F card shows that it is strapped for no interrupts and this pictured version of the card actually connects to different lines on the address bus in the ISA connector. My card uses address lines 0, 1, 2, and 8 through 15. In the other card's picture, it uses address lines 0 through 10 as far as I can tell. I don't know if it makes any difference which address lines the card accesses but I find it curious as I also have Christoph's book on how to build the HP-IL I/F card and I would like to figure out how he designed his card. I haven't done this yet as I have spent the rest of my time today working on this problem by adjusting the settings in the PC BIOS.
I disabled the MB from stopping booting on any errors and I was able to get the PC to boot once with the I/F card plugged in. It hasn't happened since but in comparing the I/O ranges and interrupts in use by the hardware through XP, IRQ 7 and I/O range 1700 looks like a good choice.
I'll keep chasing this down and if you have any insights into this mystery, I would appreciate it.