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

TEAC 55-GS SCSI Floppy Drive Issues

  • Filter
  • Time
  • Show
Clear All
new posts

    TEAC 55-GS SCSI Floppy Drive Issues

    I've been trying to get a a TEAC FD-55GS working in DOS for several days now with no luck. I just can't get the SCSI card to recognize the device. I'm wondering if anyone has been able to successfully get one of these to work in DOS and if you had, what jumper settings and SCSI Card did you use?

    I have pulled the floppy drive (a TEAC FD-55GFR 701-U) and tested it with a regular floppy controller and it works fine. I was able to format disks, read and write with no issue. Scandisks showed perfect disks. The disks were readable in other 1.2mb drives. It appears that the floppy drive is ok - at least with a PC floppy controller. The only physical issue I can see wrong with the drive is that the DS3 jumpers are broken off, but I don't see that as a problem.

    I tried using the drive with a TEAC FC-1 card and it acts the same. The SCSI card does not recognize FC-1 SCSI bridge/controller. Based on my experience with the FC-1, this is typical behavior when your floppy drive is not compatible with the FC-1 or not correctly jumpered. This FC-1 tests and works fine with compatible 1.44MB drives, but does not work with the 1.2MB floppy drive.

    Documentation is pretty thin. I did find this configuration section in some kind of industrial automation device made by Foxboro. I've spent hours trying various jumper settings. I think the only thing left to try are different SCSI cards. I'm currently using a Future Domain card, but I have an Adaptec 1542CP as well as a Trantor T160 on the way.

    I guess the questions are:

    What floppy drives are compatible with the TEAC-55GS. The Foxboro documentation lists FD-55GFR-141-U and FD-55GFR-701-U. Are there more compatible floppy drives than these 2?
    Does the model even matter? Will any FD-55GFR work?
    What Jumper settings on the 13332137-00F bridge/controller work?
    What SCSI Cards are known to work?

    I keep thinking that this particular model might have been made for a specific system and therefore will never work in DOS. The Foxboro documentation indicate that's a UNIX based system.

    Any other suggestions or information would be much appreciated. Thanks!

    Last edited by bolex; May 2, 2021, 12:41 PM.

    The big difference between a 55GF and a 235HG is that the disk spins at 360 RPM in the 55GF and 300 in the 235HG. You could set the jumpers on the GF to run in "dual speed" mode, which would drop the low-density spin to 300 RPM, but stay in 360 RPM for high. That might work, but I'm not optimistic--and you'd be stuck with using the 5.25" low-density as a 720K drive (i.e. no 360K floppies). The high density mode of the 55FG is more akin to the 1.6MB mode of the FD05HGS, but notice on PDF page 50 what the assignment of the density pins are.
    Reach me: vcfblackhole _at_ protonmail dot com.


      I would be happy to get it working as a 720K drive just to see the device show up during startup. I've tried just about every jumper combination available. I just don't think the floppy is reporting a "Ready" state to the controller for some reason. I'm almost leaning to the idea that that part of the floppy is not working properly. Those pins U0, U1, U3 are not used in the PC world, but these SCSI floppy need those jumpers set and working to be configured correctly. I think I'm going to try to find another floppy drive and see.

      The 55GS brochure says it will read all modes but will only write the 96TPI formats - which is interesting. I thought that this would be something the SCSI bridge would handle, but you might be right in that it's wholly dependent on how the floppy is configured.



        Have you tried using a plain old FD55B (360K) drive to see if you can at least 360KB floppies?
        Reach me: vcfblackhole _at_ protonmail dot com.


          I, unfortunately, don't have a FD55B handy. I did try a Teac 55FV - which is a weird 96tpi 80 track drive. It behaved the same. In a few days I'll try different SCSI cards. I'm also going to try to find a FD-55GFR 141-U - which is mentioned in the in the documentation above. Based on a sold ebay listing, it appears that It has a few more jumpers than the drive I'm working with now. Maybe that will make the difference.


            I think bitsavers has a rundown on jumpers. I do know that the original ED (3.5" 2.8 FD235J drives packaged with the FC-1 have lots of jumpers. You could also play with sending SCSI CDBs directly to the controller. I've had to do that with a few old SCSI devices to figure out what's what.
            Reach me: vcfblackhole _at_ protonmail dot com.


              I found a source for two more of the FD-55GS drives. They'll be here next week sometime. I also have a local friend who has a 55GFR he's going to sell me.

              I tried a Trantor SCSI card and it behaved exactly the same as the Future Domain one, so I'm really leaning toward a bad floppy drive. I guess I'll find out when I get the new drives in. I'll let you know how it goes next week.

              On another note, I found an SMS OMTI SCSI Floppy Bridge. So it looks like I might have a few options to play around with.


                Not to be obtuse but is there a reason you need to uses a scsi fdd? I.e. is this a must have for an exotic system or is more of a hey wouldn't be cool kind of a thing?
                Current Wish List: 1. IBM 7531 Industrial Series PC 2. NEC MultiSync XL (JC-2001) Monitor 3. MicroSolutions UniDOS card 4. Compaq 14" VGA CRT Monitor (the one that came with the SystemPro). 5. Stacker HW CoProcessor Board MCA BUS. If you have any of the above for sale please PM me. Thank you!


                  Haha! There is no reason whatsoever other than I want to figure it out. It's just the current rabbit hole I've gone down. Give it time, I'm sure I'll find something even more stupid to play with.


                    I'm making a bit of progress. Unlike the FC-1 Controllers that get their power from the floppy drive, this original FC-1 in the 55GS needs a power source. I just rigged up some small clips to +5 & G and the SCSI card was able to see the floppy drive and the driver was able to load. I assume this is the correct power since that cap right there is a 10V 100uf, but truthfully who knows. I can't find any documentation. Drive is still not working (it does not seem to be seeking), but at least it's something I can troubleshoot.

                    Does anyone know where I can get a source for this female power connector?




                      I finally was able to get this drive working. It works amazingly well.

                      I don't think I've ever been so frustrated with getting something working before. There is just no documentation on how to use these drives. None. So it was a ton of hit and miss and there are so many jumper possibilities. Hopefully I can help someone avoid this in the future.

                      I did have to make a power cable for the FC-1 Controller. The connector was a JST-XH 2 pin connector. I have 2 other FC1 controller boards and neither of them needed their own power and somehow used power from the floppy cable. The 2 earliest FC-1 Controllers need external power it seems. This is just 5 volts from a standard power connector.


                      I found someone that had an 55GS in stock and they sent me a picture and the jumper settings were different from what I had above from the Foxboro Manual. I tried them and they worked! The Foxboro manual is not correct for DOS and so these are the correct Jumper settings on the Floppy Drive that are working for me.


                      These are the FC1 Jumper settings I'm using. On the FC-1 Controllers, the G, F, J jumpers signify the TEAC drive compatible modes and sizes of drives you want to use. So these jumpers mean that it is compatible with G and F type floppy drives (1.2MB and 720K - The 360K is a given). The newer FC-1's have a J jumper for 2.8MB drives. I could not get this to work with any other drive so I think that these early FC1s are only compatible with the Teac Model FD-55GFR-141-U and FD-44GFR-701U.


                      The Trantor TSCSI.SYS DOS driver seems to work the best of all the DOS Drivers I tried. Maybe in a while I'll check out some windows drivers to see if they are compatible but for DOS this is by far the best working driver.


                      The Trantor TFORMAT.COM works best for formatting. The only drawback is that it does not allow you to format a quad density disk. It does appear that it will read quad density disks. So with the Trantor driver you can read and write 360K and 1.2MB disks and read 720K. This is different than what the brochure said.

                      One note on SCSI cards. I tried an Adaptec 1542C, a Future Domain PNP-1630 and a Trantor T-160. The Future Domain card seems to work best. The Adaptec worked fine, but it did not like the TFORMAT Utility that well. The utility would run and format disks just fine, but it would lock up the PC on exit. The Future Domain card did not do this. The trantor card worked really well too, but it wanted to boot from SCSI no matter what so you can't have floppy disks inserted when you boot the computer. I couldn't figure out how to stop if from doing this. So I'm using the Future Domain SCSI card and it works great.


                      I added this to my multi-floppy desktop. It's the 13th floppy in that system. haha!



                        That's an impressive looking tower. Nice work.
                        Surely not everyone was Kung-Fu fighting


                          O.k. I can see 8 drives (2x2.88,2x1.2,2x360,and 2 x 8") but what do the other 5 do?
                          Current Wish List: 1. IBM 7531 Industrial Series PC 2. NEC MultiSync XL (JC-2001) Monitor 3. MicroSolutions UniDOS card 4. Compaq 14" VGA CRT Monitor (the one that came with the SystemPro). 5. Stacker HW CoProcessor Board MCA BUS. If you have any of the above for sale please PM me. Thank you!


                            Originally posted by Shadow Lord View Post
                            O.k. I can see 8 drives (2x2.88,2x1.2,2x360,and 2 x 8") but what do the other 5 do?
                            How about loading it up with gizmos like CF readers, etc.?

                            Surely not everyone was Kung-Fu fighting


                              Originally posted by Shadow Lord View Post
                              O.k. I can see 8 drives (2x2.88,2x1.2,2x360,and 2 x 8") but what do the other 5 do?
                              There really is no point to the system other than to keep adding floppies. The 4 floppy controllers that I'm using work great as far as the system goes, but are not really good for disk imaging.

                              In all reality, it would make more sense to have a good controller that passes all the Dunfield tests for disk imaging and have multiple PC's. Specifically if disk imaging is the long term goal. I just wanted to say I built a PC with 14 floppy drives. (The 14th is going in later this week). haha!

                              I do have to say that the SCSI drives are excellent for formatting and checking disks. The low-level format utility that is part of the trantor driver works amazingly well.
                              Last edited by bolex; May 19, 2021, 09:54 AM.