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

MFM controller for S-100

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

    MFM controller for S-100

    A lot of threads on MFM hard drives seems to end with people saying how crap they are and throwing them out.
    In the spirit of this forum, I'm hoping to save one just for the heck of it.
    It's an NEC-D3142, 42Mb. On power on, it spins up and seems to seek track 0. It came with an ISA-bus controller card from a Wang 80386 PC, but the card doesn't work in a standard PC ISA slot as far as I can determine in any AT mobo I have - possibly BIOS are all too new.
    I have an S-100 system (IMS 5000) that I'm working on. The BIOS can be configured for MFM HDD.
    If MFM drives have a reputation for failing, it stands to reason there should be some controller cards around that have no functioning disks to run on them.
    Any ideas on where such s-100 MFM controller a card might be found (other than dumpsters)?
    Did all MFM controllers have the same 34pin+20pin dual cable connections with the same pinouts?
    Also, any source for documentation on the NEC-D3142. It seems to have been a pretty common drive in its time?
    Any help or advice appreciated

    #2
    drives

    Well, first here's the man page for the drive:
    http://support.necam.com/oem/HDD/D3142.asp

    MFM gets a bit of a bad rep by folks coming of IDE & ATA spec stuff, which is pretty much plug and play. MFM drive types were often closely bound to the controller cards.
    If you change your mind back to ISA, there's probably a controller out there.

    Probably not the earliest ones, but If you can dig up a Cromemco STDC card. that should work with your drive.

    patscc

    Comment


      #3
      Did someone say Cromemco? Yes, I do have one or two STDC's but not cheap...

      Now if you wanted a WDI or WDI-II then we could definitely talk, but although they're MFM they're probably not what you're looking for. In answer to your other question, although MFM is commonly used to describe a hard disk using the ST412/506 34&20 pin interface, technically it only refers to the recording method and not the computer interface.

      The IMI interface that the WDI's use is an example; the later 5 1/4" IMI drives could be bought either way, the same HDA and analogue board with either an IMI (single 34-pin cable) or ST506 interface board, for use with either a WDI or STDC respectively. As a matter of fact an upgrade kit was available consisting of an ST-506 interface board and the matching STDC controller.

      Comment


        #4
        to patssc - thanks for the specs link and other info

        to MikeS - In this case, how does "not cheap" translate into $$?
        I haven't seen anything pop up on ebay in the few weeks since I've been interested.

        Comment


          #5
          I gutted a large CPM system yesterday, and inside I found a 8" floppy drive and a MFM HDD connected to a daugtherboard which in turn connected to a standard 8" floppy drive port on the controller.

          I wonder what it's for ? Maybe it uses the HDD to create logical drives or something?
          Current machines:
          PCs: IBM PC XT 640K, IBM PC XT 256K ,IBM PC XT , 2x IBM PC AT, Compaq Portable I, Compaq Portable II, Compaq Portable I/286, Philips Logic Analyzer XT clone, IBM PS/2 Model 30 286 , HP 95X, HP200LX (2x),Compaq SLT/286.
          Apple: Macintosh 512k, Macintosh SE, Macintosh Classic, PowerBook 170, iBook Clamshell, iBook G3,iMac G4 , TiBook's, Apple IIc, Many newer machines (G4, G5, Intel..), 20th Anniversary Mac
          Others: Commodore 64C,Amiga A500, CCS S-100 System, SNES,

          Wanted: Macintosh 128k, Hard Disk 20, System disks and games for the Mac

          Comment


            #6
            Originally posted by RickNel View Post
            to patssc - thanks for the specs link and other info

            to MikeS - In this case, how does "not cheap" translate into $$?
            I haven't seen anything pop up on ebay in the few weeks since I've been interested.
            Yeah, S-100 HD controllers are pretty thin on the ground; I wonder how hard it would be to make an S-100<>ISA bridge board... Andrew, are you reading this?

            I'd say around $150 for an STDC, but frankly, unless you need one for a Cromemco I wouldn't recommend it. It's a fairly intelligent controller with a Z80 coprocessor, DMA controller, 64K RAM, 8K ROM etc. that reads and buffers an entire track at a time, so I'd think a driver or BIOS would be a bit of a challenge even if you did want to pay my exorbitant price...

            m

            Comment


              #7
              Outside of the Compupro Disk 3, I don't think I've ever run across an S100 ST506-interface controller. Even the Disk3 is very late in S100 history (~1984).

              What's more common are SASI interface boards for S100 (little more than a parallel port) that connect to something like an outboard WD1001 controller hooking up to an 8" SA1000-type drive.
              Reach me: vcfblackhole _at_ protonmail dot com.

              Comment


                #8
                Originally posted by Chuck(G) View Post
                Outside of the Compupro Disk 3, I don't think I've ever run across an S100 ST506-interface controller. Even the Disk3 is very late in S100 history (~1984).

                What's more common are SASI interface boards for S100 (little more than a parallel port) that connect to something like an outboard WD1001 controller hooking up to an 8" SA1000-type drive.
                Well, Vector Graphic had at least one, basically a floppy controller with a few extra bits added to connect to a "real" ST-506.

                Guess we've come full circle with IDE putting most of the smarts back onto the drive

                Comment


                  #9
                  Here's that card I mentioned... Seems to be MFM-to-SASI (Shugart) controller

                  Xebec controller
                  Last edited by QuantumII; May 26, 2009, 11:21 AM.
                  Current machines:
                  PCs: IBM PC XT 640K, IBM PC XT 256K ,IBM PC XT , 2x IBM PC AT, Compaq Portable I, Compaq Portable II, Compaq Portable I/286, Philips Logic Analyzer XT clone, IBM PS/2 Model 30 286 , HP 95X, HP200LX (2x),Compaq SLT/286.
                  Apple: Macintosh 512k, Macintosh SE, Macintosh Classic, PowerBook 170, iBook Clamshell, iBook G3,iMac G4 , TiBook's, Apple IIc, Many newer machines (G4, G5, Intel..), 20th Anniversary Mac
                  Others: Commodore 64C,Amiga A500, CCS S-100 System, SNES,

                  Wanted: Macintosh 128k, Hard Disk 20, System disks and games for the Mac

                  Comment


                    #10
                    Originally posted by QuantumII View Post
                    I can take a picture of the weird 8"-floppy-connector-to-MFM card.

                    Will post it here shortly.
                    Sounds intriguing all right; what's the make & model of the CP/M box and the drive?

                    Comment


                      #11
                      Originally posted by MikeS View Post
                      Sounds intriguing all right; what's the make & model of the CP/M box and the drive?
                      It was in a Tandberg TDV 2324 (Norwegian brand) CPM machine. I rescued the MFM HDD; the controller and the 8" floppy drive.

                      The HDD is a Rodime Series 200 , and the floppy drive is a Shugart.
                      Current machines:
                      PCs: IBM PC XT 640K, IBM PC XT 256K ,IBM PC XT , 2x IBM PC AT, Compaq Portable I, Compaq Portable II, Compaq Portable I/286, Philips Logic Analyzer XT clone, IBM PS/2 Model 30 286 , HP 95X, HP200LX (2x),Compaq SLT/286.
                      Apple: Macintosh 512k, Macintosh SE, Macintosh Classic, PowerBook 170, iBook Clamshell, iBook G3,iMac G4 , TiBook's, Apple IIc, Many newer machines (G4, G5, Intel..), 20th Anniversary Mac
                      Others: Commodore 64C,Amiga A500, CCS S-100 System, SNES,

                      Wanted: Macintosh 128k, Hard Disk 20, System disks and games for the Mac

                      Comment


                        #12
                        Originally posted by QuantumII View Post
                        Here's that card I mentioned... Seems to be MFM-to-SASI (Shugart) controller

                        Xebec controller
                        Yup, just like the WD1000/1001--insanely easy to imterface to. The WD controllers used the Signetics 8x300-series bipolar controllers. You can probably still find the WD controllers within the TRS-80 community.

                        My first IBM 5150 hard disk was a Shugart SA1004 and a WD1001, hooked to a homemade interface card in the PC.
                        Reach me: vcfblackhole _at_ protonmail dot com.

                        Comment


                          #13
                          Ah yes; I've got the SCSI version of the Xebec MFM bridge. Never figured out what to do with it though.

                          Comment


                            #14
                            Originally posted by MikeS View Post
                            Ah yes; I've got the SCSI version of the Xebec MFM bridge. Never figured out what to do with it though.
                            I've got a couple of OMTI RLL-to-SCSI cards somewhere. They're identified as having the "Mac SCSI" ROMs. At one time, MFM/RLL drives were cheap in comparison to SCSI drives. I think this sort of bridge card was useful as a money-saver. I used mine (wtih some external "glue" logic) to interface an Atari ST to an MFM hard drive.

                            Well, there's your "S100 MFM controller". SCSI isn't much more than a couple of parallel ports and software following a protocol definition, so it should be pretty straightforward to interface one of the SCSI-MFM bridge boards to an S100 parallel card.
                            Reach me: vcfblackhole _at_ protonmail dot com.

                            Comment


                              #15
                              HDD as virtual FDDs

                              My IMS International system docs (1981) refer to an optional "hard disk sub-system" with removable cartridges in optional capacities of 32mB, 64mB and 96mB, in each case presented to CP/M as multiple "diskette drives" of 8mB capacity. No hardware or vendor standard is mentioned, but maybe that configuration suggests a Shugart-style controller (SASI)?

                              Does anyone have information/memories on that style of HDD sub-system?

                              The IMS system's FDC is Shugart-compatible card driving two Tandon 5.25 FDDs.

                              The FDC card does not have any connectors or headers other than the two 34pin FDD connectors, so I guess the HDD subsystem was driven from its own s-100 card, not from a daughter-board like the interesting XEBEC shown by MikeS.

                              So some kind of s-100 card must have been out there from around 1980 to as long as these machines were still running.

                              My puzzle is still - how to connect a NEC D3142 to a S-100 system.

                              Comment

                              Working...
                              X