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

Unique S-100 computer (Z-80/Vector Graphic/Micropolis)

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

    Yes they only start spinning once they're selected, and stop spinning after about 5 seconds. I only hear the sound of the hub spinning, no head loading sounds at all.

    Comment


      So I decided to go through and give everything another good cleaning. Let the ribbon cable soak with some DeOxIt on the leads and cleaned up the connectors on the drive PCB. Making some progress! Now the solenoid engages and the head snaps down. The worm gear engages and moves the head all the way to the outer edge of the disk. I can see once it reaches the edge, the 0-track switch does get engaged. However, the application is still saying "Seek to track 0 failed". Same thing happens for both drives. But now at least I can see the head only engages on the correct drive when I enter 0 or 1.
      Last edited by nullvalue; May 13, 2020, 07:18 AM.

      Comment


        Great progress! Use a scope and see if the track 0 signal on the interface cable (pin 26) is getting asserted (asserted = low). Look at the signal on the drive PCB and then on the floppy controller PCB and see where it is failing. Trace backward as required to its origination on the drive PCB, and/or forward to it's final destination in the latch on the floppy controller end.

        Mike

        Comment


          Awesome, will do - is the track 0 signal simply asserted by that switch, or is there more involved than that?
          Last edited by nullvalue; May 13, 2020, 08:32 AM.

          Comment


            The track 0 switches goes through a couple of connectors and gates before driving the cable connector. You can find schematics towards the end of this manual: https://deramp.com/downloads/floppy_...6%20Manual.pdf.

            These schematics are for the single drive board, not the two-drive board like you have, but it'll give you the idea.

            The disk controller schematic in the computer is here: https://deramp.com/downloads/vector_...Controller.pdf

            Mike

            Comment


              Well I didn't really do anything but I'm back to the head not moving at all again. For drive #1, I can fool it into thinking it found track 0 by just starting it in that position. I just wanted to test the app. Sending XMODEM data over port C seems to work because after a while, it spins up the disk and I can assume it's trying to write. Of course it fails (write failure on track 0). I can't get fool it for drive #0 though for some reason. But for now I'm back to trying to figure out why the heads won't move. The correct solenoid engages and the head snaps down.. but the steppers aren't working. I took it apart and meticulously cleaned every pin/connector and the inside of the ribbon cable. Everywhere a connection is made. Still can't get it to work again.

              Comment


                I swear I may have no hair left at the end of this. For some reason it just decided to work.. head's moving.. Do you think I should replace the caps on the board? So I tried writing a disk.. tried a couple times now.. blank disk in, both drive 0 and drive 1. Once the transfer hits 52,864 bytes it starts writing. Every time I get a "Write failure on track 0, sector 7." (although the sector that fails seems to change) - any thoughts?

                Edit: side question - while I do want to get the actual hardware floppy drive working, do you think it would be possible to get a Gotek working with this setup?
                Last edited by nullvalue; May 18, 2020, 05:45 PM.

                Comment


                  If you’re to the point that PC2FLOP is writing and verifying, then it is failing on the read. It’s time to calibrate the pots on the FDC. It’s pretty easy to do. Look at the “Tests and Adjustments” section of the controller manual https://deramp.com/downloads/vector_...Controller.pdf

                  Mike

                  Comment


                    Thanks I'll check it out! But how do we know it's writing successfully and failing to read - and not just failing to write? Or would the same adjustments fix this?

                    Also how would I invoke the read/write operations it's talking about in tests 2.1.3 and 2.1.4?
                    Last edited by nullvalue; May 19, 2020, 06:03 PM.

                    Comment


                      From what I recall, you can get the measurements while it’s stuck in the loop trying to boot.

                      Mike

                      Comment


                        Originally posted by deramp5113 View Post
                        From what I recall, you can get the measurements while it’s stuck in the loop trying to boot.

                        Mike
                        I performed the Center Frequency Test (2.1.2) - it was pretty close, but made a minor tweak. Same for the 2us Single-Shot Test (2.1.3) - it was off by a little bit so I made an adjustment. I tested this during a boot attempt.

                        However, for the 1us Single-Shot Test (2.1.4), I am not seeing any activity on the scope for A14, pin 3. What do you think might cause that?

                        Tried writing another disk for the heck of it, same result.

                        Comment


                          Originally posted by nullvalue View Post
                          However, for the 1us Single-Shot Test (2.1.4), I am not seeing any activity on the scope for A14, pin 3. What do you think might cause that?
                          Looks like the pin number is wrong in that version of the manual. Look at pin 13, not 3.

                          Mike

                          Comment


                            Originally posted by deramp5113 View Post
                            Looks like the pin number is wrong in that version of the manual. Look at pin 13, not 3.

                            Mike
                            Thanks, that was it! So I adjusted that one (I think it was pretty much dead on already)... tried creating a disk in both drives.. same result - "Write failure on track 0, sector 7"

                            Comment


                              Going through some of the other troubleshooting steps. I've verified voltages and the bootstrap prom checksum. Would it be possible for you to send me an MDOS disk with the "DIAG" command to carry out the rest of the read/write troubleshooting tasks? or is there anything else I could try?

                              Comment


                                Originally posted by nullvalue View Post
                                Going through some of the other troubleshooting steps. I've verified voltages and the bootstrap prom checksum. Would it be possible for you to send me an MDOS disk with the "DIAG" command to carry out the rest of the read/write troubleshooting tasks? or is there anything else I could try?
                                I'm sure these are discussed somewhere in the thread, but let's double check the following:

                                1) You're using hard sector disks with 16 hard sectors (not 10, not soft-sectored)
                                2) The write protect notch is not covered.
                                3) You're inserting the disk with the label side up (based on the picture I see of your drive)

                                Mike

                                Comment

                                Working...
                                X