XT-IDE on PCjr

[southernbob]

On the memory count problem, a couple of things you might want to try:
736k mode - change the data pattern from AA55h (assuming you are using that )
to 411Fh. If your program is writing into B8000h then this will fill the screen with
white A's on a blue background. The AA55h pattern, if the video buffer is written
with this will give - the 55 is the attribute which will give MAGENTA as a background
and MAGENTA as a foreground color and the screen will be MAGENTA.

704K mode - check with debug to see if the data pattern fills up the area beteen
B0000h and B8000h even thought the count shows that it stopped at B0000h.

In either case the program would be suspect where it is doing the stop
testing comparision.

Just my suggestions.

On the cartridge space problem, as you said, apparently the signal (-mem on card)
is not activated on access to cartridge space tri-stateing the data bus transceiver.
This probably is where the signal (-rom sel) needs to be OR'ed with (-mem on card)
to get cartridge space access, similiar to what I had to do to get the CS's for the
cartridge space mentioned in a previous append. I don't know what kind of module
that is that generates those signals but it seems to determine address ranges using
the upper address lines.

Bob

[Brutman]

Still poking at it - don't lose faith!

[Brutman]

Alan and I have been talking ... for the benefit of our two other forum members who might be interested ...

I have a BIOS that loads and identifies a drive, which is good - that shows that the card/BIOS can send commands and get a response. The response for an ID command looks just like a sector read so in theory sector reads will work.

Alan knocked down one FPGA programming bug that slowed things down a bit. We're working to figure out the second problem - the IDE data window isn't working exactly as advertised, but it is usable and still far faster than the PIO method. After that there is a third problem - I'm losing the drive after it IDs. (It won't ID twice in a row.) Having the POST display on the card has helped a lot and will help while debugging that problem.


Mike

[hexsane]

I think there are more lurkers than you think. Wouldn't hurt to cross post updates to the VC forum. I know when this idea came up (and my thread was hijacked) there was a lot of interest.

-Matt

[Brutman]

Off-topic:

I would like the lurkers to de-lurk and participate. There are so many projects going on both here and at the VC Forum that are interesting and useful for this old hardware. Besides the XT-IDE (which is very amenable to the Jr) there is a keyboard converter project which we could also adapt for the Jr and I am sure some other projects that I missed.

I have had the PCjr web pages up since 2000 and we have had some form of PCjr specific forum since 2001, a full 2 years before VC Forum. Back then Brian Heise hosted it with GNX. I still have the raw database files and I need to learn MS Access and try to reconstruct the threads to make them available again. I like having our own little corner over here with a maniacal control freak moderator to keep things nice and clean, but I definitely wonder if this is worth doing with so few active people. It's not costing much so it continues to live on ...

We do get some people who register and never participate - I wonder if they are just looking at the WANTED and FOR SALE sections, because registration is required for those. It doesn't make much of a difference - plain PCjrs are hard to give away, and that is usually all that appears.

Anyway, back on topic .. I would rather cross-post status when we have it running. Most people with 1/2 to 3/4s of a brain know there is one PCjr forum in the universe, and this is it. : - )


Mike

[Trixter]

I de-lurk when it comes to programming or gaming fun, but I regretfully cannot participate in any hardware discussions as I lack expertise in that area.

I am looking forward to an XT-IDE sidecar -- it would make my dream of working on a PCjr demo possible. (It is technically possible to do it with just a single drive, but it is far from practical to do so.)

[Vorticon]

It's all a matter of what one can contribute. While I have been following with great interest the XT-IDE topic as it unfolded, unfortunately most of what was being discussed was way over my head...
That said, I for one am still here and log on at least once a week to see what's new Please don't take the forum away because it's what got me into the PCJr in the first place!

[MattCarp]

de-lurking!

I was hoping to meet Alan recently, as he lives right around the corner. I'm certainly interested in the result! Don't know if I can make the time to participate, but perhaps it would help to get a status update that summarizes the things that work and the things to do?

I do like the PCjr forum, although if cost ever got to be an issue, I'd hope we could get a jr forum at Klein's site for the occasional chatter.

I still have the raw database files and I need to learn MS Access and try to reconstruct the threads to make them available again.

Um, I know a lot of us could help with that, plus there's a lot of good information in that archive. Why not make the files available and we can crowdsource the effort?

[alanh]

If you're in the Atlanta area, check out http://atlhcs.org/. I missed the Jan meeting as I was at the Cotton Bowl. But will be there Saturday. I'll bring the JR.

I've been time starved, however my 386 is up and running of the ISA version of the board. Basic read/write tests also work on the JR, but I haven't had time to test further or attempt to write a BIOS.

[Brutman]

Um, I know a lot of us could help with that, plus there's a lot of good information in that archive. Why not make the files available and we can crowdsource the effort?

I'll take that as an offer to volunteer ... I'll get the zip file ready for you.