Announcement

Collapse

Forum Rules and Etiquette

Our mission ...

This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

This forum has been around in this format for over 15 years. These rules and guidelines help us maintain a healthy and active community, and we moderate the forum to keep things on track. Please familiarize yourself with these rules and guidelines.


Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.


Rule 2: Stay close to the original topic being discussed
  • If you are starting a new thread choose a reasonable sub-forum to start your thread. (If you choose incorrectly don't worry, we can fix that.)
  • If you are responding to a thread, stay on topic - the original poster was trying to achieve something. You can always start a new thread instead of potentially "hijacking" an existing thread.



Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
  • This is not a chat room. If you are taking less than 30 seconds to make a post then you are probably doing something wrong. A post should be on topic, clear, and contribute something meaningful to the discussion. If people read your posts and feel that their time as been wasted, they will stop reading your posts. Worse yet, they will stop visiting and we'll lose their experience and contributions.
  • Do not bump threads.
  • Do not "necro-post" unless you are following up to a specific person on a specific thread. And even then, that person may have moved on. Just start a new thread for your related topic.
  • Use the Private Message system for posts that are targeted at a specific person.


Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

Here are some obvious examples of when you should not reply to a thread and use the PM system instead:
  • "PM Sent!": Do not tell the rest of us that you sent a PM ... the forum software will tell the other person that they have a PM waiting.
  • "How much is shipping to ....": This is a very specific and directed question that is not of interest to anybody else.


Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.


Reporting problematic posts

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

If you are unsure you may consider sending a private message to a moderator instead.


New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.


Other suggestions
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
See more
See less

8 bit IDE (XTA) Replacement Project

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #91
    Originally posted by jafir View Post
    Has anyone ran spinrite with one of these drives? Does it talk about the interleave and being able to change it?
    Supposedly at least some XTA drives use sector translation, so trying to run a utility like that against one has the possibility of bricking it. 1:3 is pretty good performance for an XT class controller when you consider IBM went with 1:6 on the original XT.
    My Retro-computing YouTube Channel (updates... eventually?): Paleozoic PCs Also: Blogspot

    Comment


      #92
      Originally posted by vwestlife View Post
      Any hope for interleaves lower than 3:1 or is that simply as fast as 8-bit XTA can go?
      According to this hard drive documentation:

      https://stason.org/TULARC/pc/hard-dr...HH-IDE-XT.html

      it was possible to get 2:1 interleave using demand DMA mode with the WD Super BIOS and this drive configured accordingly.

      It is the drive that what was in my TL/2.

      Comment


        #93
        Originally posted by JayesonLS View Post
        According to this hard drive documentation:

        https://stason.org/TULARC/pc/hard-dr...HH-IDE-XT.html

        it was possible to get 2:1 interleave using demand DMA mode with the WD Super BIOS and this drive configured accordingly.
        It says "Western Digital's Super BIOS version 2.1 or greater can program the controller for DMA demand mode." Unfortunately the newest BIOS we have a copy of is 1.1. My own WDXT-150 card has 1.0 on it.

        I believe the built-in SmartDrive interface in the later Tandy 1000s supports DMA mode, but I don't know what interleave it uses. I can dump my 1000RL's ROM if someone wants to try to find the XTA code in it.

        Comment


          #94
          Originally posted by vwestlife View Post
          It says "Western Digital's Super BIOS version 2.1 or greater can program the controller for DMA demand mode." Unfortunately the newest BIOS we have a copy of is 1.1. My own WDXT-150 card has 1.0 on it.
          It is so strange to me that there might be a whole major version jump on an XTA BIOS. It seems to me like this would have been a modest business area for them which obviously didn't warrant ongoing investment. I wonder it the note be in error and refers to an MFM BIOS version.

          It would be useful to have a copy of the 1.0 BIOS for testing.

          Originally posted by vwestlife View Post
          I believe the built-in SmartDrive interface in the later Tandy 1000s supports DMA mode, but I don't know what interleave it uses. I can dump my 1000RL's ROM if someone wants to try to find the XTA code in it.
          That would be extremely useful thanks.

          Comment


            #95
            I finished up my XTA interface card design and ordered boards for testing. I'll follow up when they get here and I have had a chance to build one up.

            I have also spent a bit more time looking at the PS/2 Model 30 286 BIOS. I am even more convinced now that nothing like the "standard" XTA style drives. I also found where it sets up the drive parameters and it looks like it supports the standard AT drive types up to type 37. The drive time is determined by reading from the drive which is great. The code where the it computes the drive type number is quite complicated and I have not yet determined whether it can actually select from any of the 37 types. If it can, type 9 is a massive 117,504,000 bytes. Bigger anyway than the 40 megs we are going to get with XTA. A solid state replacement should be able to best-fit a drive type to the size of the installed SD card.

            If someone would like to figure out the IBM drive protocols and emulate in PCem, that would be super helpful . The PS/2 Model 30 286 is already configured in PCem, it just needs implementation of the hard drive. ghidra work so far for the PS/2 Model 30 286 BIOS is located here: https://github.com/JayesonLS/8bit-id...e30_286_Ghidra

            Comment


              #96
              An XTA card popped up on ebay for a somewhat reasonable price if anyone here is looking

              https://www.ebay.com/itm/324792162361

              Comment


                #97
                Hmmm, I started off on this thread thinking that folks owning systems with integrated XTA support were looking for an XTA drive substitute. It turns out that I was wrong--it seems that people are looking for an XTA interface (too brain-dead to call it a controller) board for systems that don't support XTA.

                Given such a drive, and needing to retrieve data from it, I'm still of the opinion that it could be done with a bidirectional printer port and a bit of software--and maybe a bit of hardware (<$10 worth).
                Reach me: vcfblackhole _at_ protonmail dot com.

                Comment


                  #98
                  Originally posted by Chuck(G) View Post
                  Hmmm, I started off on this thread thinking that folks owning systems with integrated XTA support were looking for an XTA drive substitute. It turns out that I was wrong--it seems that people are looking for an XTA interface (too brain-dead to call it a controller) board for systems that don't support XTA.

                  Given such a drive, and needing to retrieve data from it, I'm still of the opinion that it could be done with a bidirectional printer port and a bit of software--and maybe a bit of hardware (<$10 worth).
                  I am wondering if it is possible to move the XTA interface solution posts into another thread. There does seem to be two conversations woven together.

                  I am not sure how much of a demand for an interface solution. I think perhaps VWestlife was just wanting to understand how XTA might map into the XT-IDE ecosystem. What I didn't answer earlier, is that it would be possible to hook an XTA drive up to an XT-IDE, or a standard ATA interface, with a modified cable and an updated XT-IDE BIOS. The modified cable would be needed to avoid shorting signals to ground. Maybe you could be careful with the code to always drive 0's as needed but it sounds like trouble to me. The BIOS changes would be significant - I am not very familiar with ATA but the XTA registers/protocols do not look to be very similar. Plus the different XT-IDE variants have different register arrangements.

                  For what demand there might be for an interface solution, I do think it would go beyond the need to get data off old drives. I know I am not the only person who loves the sounds from a working stepper motor drive. For the solid state XTA replacement drive, I was seriously considering adding a stepper motor for appropriate sounds and timing. I guess I am again. I mean listen to these chirps: https://www.youtube.com/watch?v=sGEjB5yd5rA

                  Comment


                    #99
                    Yes, but all those old 1980s drives are gradually heading for the big roundup in the great bitbucket in the sky...
                    Reach me: vcfblackhole _at_ protonmail dot com.

                    Comment


                      Originally posted by Chuck(G) View Post
                      Hmmm, I started off on this thread thinking that folks owning systems with integrated XTA support were looking for an XTA drive substitute.
                      Same here. I have a Comoodore PC20-III that has been equipped with a XT-IDE + CF but would not say 'no' to a XTA variant.

                      With kind regards / met vriendelijke groet, Ruud Baltissen

                      www.baltissen.org

                      Comment


                        Since it's relevant to both projects (solid-state emulation of IDE-XT drives and making a new interface for existing IDE-XT drives), I'll say here that one thing I didn't mention in my video is that the cross-compatibility between brands in not universal. The Western Digital interface card will work with both WD and Seagate drives, but I couldn't get the Seagate interface card to work with my WD drive, even after experimenting with the jumper settings on it.

                        Also many years ago I was unable to get a MiniScribe IDE-XT drive to work with the built-in Western Digital interface in the CompuAdd 810, although I think that's just because I didn't low-level format it, and back then I didn't know that you could do so on any kind of IDE drives! FDISK did recognize the drive, but every attempt to format it using the normal DOS FORMAT command failed.

                        Comment


                          This is a good project, I have several XT class machines from Olivetti where a flash based XTA drive replacement would be nice. So I hope that the device will be small enough to fit in the space of a 3,5 or even 2.5 inch drive (Conner CP-2022XT in Olivetti Quaderno). My devices always have 20 MB drives (CHS 612 / 4 / 17) what is very limited capacity, Maybe it would be possible to switch different drive images.
                          <album>

                          Comment


                            Originally posted by vwestlife View Post
                            The Western Digital interface card will work with both WD and Seagate drives, but I couldn't get the Seagate interface card to work with my WD drive, even after experimenting with the jumper settings on it.
                            That is a great datapoint. I have not tried my WD drive on the ST05X card because I guessed it would not work. I thought from your video that you probably had not tried it. I could not get the ST351 A/X drive to work with the ST05X with the 20/30 MB jumper settings either. On one setting the drive was making horrible repeated seek sounds.

                            The issue might be something as simple as drive parameters. I think Seagate probably gathered up all possible compatibility needs in the ST351 A/X. It does have a confusing array of jumper settings - with two versions of the drive just to complicate things. There is quite a bit of info about it in Tandy faxback documents.

                            Comment


                              Originally posted by 1ST1 View Post
                              This is a good project, I have several XT class machines from Olivetti where a flash based XTA drive replacement would be nice. So I hope that the device will be small enough to fit in the space of a 3,5 or even 2.5 inch drive (Conner CP-2022XT in Olivetti Quaderno). My devices always have 20 MB drives (CHS 612 / 4 / 17) what is very limited capacity, Maybe it would be possible to switch different drive images.
                              I was not really aware that there were 2.5" XTA drives. I think I might be able to squeeze 2.5" and 3.5" connectors onto a 2.5" x 3.5" board. Will have to see what that means for mounting. For the 3.5" version, I had planned to attach the circuit board to a common sheet metal 2.5" to 3.5" adapter. Maybe that still works, and 2.5" is mounted with velcro or something.

                              It looks like Connor only had 20MB 2.5" XTA drives but they did have 20 and 40MB 3.5" XTA drives. I think there is a decent chance the Quaderno would support 40MB.

                              If someone is able, I would very much like to know what each of these Connor drives report from their size configuration register. Even with a non-working drive, you will likely be able to read the register using DOS debug.
                              Code:
                              C:\> debug
                              -i 322
                              FF            <-- this value
                              I have looked a little into the Olivetti's. The PC1 looks interesting - seems a board could be screwed to that little rail in the drive bay area. I probably need to get one for reference to support that machine properly. The combination of their apparent value and shipping to Australia is a bit daunting. But Tandy 1K's shipped from the US are occasionally palatable to me, so we'll see.

                              Regarding larger drive sizes, I know that 40MB runs out very quickly. I have been thinking a bit about large drive support. It would be possible to patch the BIOS to support larger drive sizes. That would be a lot of BIOS'es to patch and burning/replacing them is getting to be a very advanced option.

                              I think it could maybe also be done with some kind of modification to the DOS boot sector to patch the drive parameters before anything else happened during boot. It would not be trivial, but I think what would work well is some tool that adds an extended DOS partition and patches the boot sector after standard setup of the initial 40MB partition. Definitely something to experiment with later.

                              Comment


                                On needing more drive space, I think maybe what would work better would be a second SD card on the drive replacement and a device driver that gave access to it.

                                Comment

                                Working...
                                X