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

    Originally posted by deramp5113 View Post
    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
    1) Yep I purchased a box of these - fresh out of the shrink-wrapped box, I have tried 2 different disks from the box so far - https://www.ebay.com/itm/16-Hard-Sec...72.m2749.l2649
    2) Write protect notch is not covered (and "File Protect" dot is not illuminated once disk is inserted)
    3) Yes I am inserting the disk label-side up (as I insert, the write protect notch is to the left)

    Comment


      With the adjustments made, is the behavior with PC2FLOP the same on both drives?

      Mike

      Comment


        Yep I have tried both drives - the appropriate drive spins up like it's going to write (head locks down, hub spins), but both end up throwing the same error)

        Comment


          Read problems are more common than write problems because reading is a much more complex process than writing. Thatís why we checked reads first. Of course, you could just have a write problem, and since the most obvious read adjustments arenít helping, letís look at write issues next.

          You can start by trying to test and troubleshoot the write paths, or I can send you some bootable disks. The good thing about starting by writing your own disks with PC2FLOP is you bypass drive alignment problems since youíre writing and reading with the same drive. But if you canít write your own disks and you need to use a disk written by someone elseís drive, now drive alignment becomes a new source of problems. It may be quicker to try and troubleshoot the write path and maybe something obvious will jump out.

          Let me know which way you want to go.

          Mike

          Comment


            That's fine with me trying to troubleshoot write operations - how would I test write paths?

            Comment


              I would normally start looking on the drive PCB first, but your drive cabinet has a single board that controls two drives instead of a board per drive. I only have schematics for the latter. Have you found and downloaded schematics for the PCB in your drive cabinet? If so, point me to it and I’ll download a copy.

              Mike

              Comment


                Yes I believe this is it:
                http://www.bitsavers.org/pdf/micropo...nual_Feb79.pdf

                The board pictured in 4-3 is very similar to mine. There are some differences with connector positions but its the closest I've found. The schematic starts on page 132.

                Here is a closeup of my drive cabinet board
                20200522_205335.jpg

                Comment


                  Actually, before we look for a write issue, have you looked at the 60hz strobe lines on the hub disc? How is the drive speed?

                  Mike

                  Comment


                    Actually I just realized I hadn't tried something after my adjustments.. I was never sure which head connector went to which drive on the internal board. Every test previously I'd swap the connectors around in case they were backwards. So now I swapped them and I was able to get a successful write! It said the disk was created at the end. I wrote the 56k "Vector CPM for Micropolis.vgi" image. However, I am unable to boot from it using the 'B' monitor command. The disk drive engages but just spins and nothing happens.

                    How would I check the strobe lines? The speed seems ok but how can I measure it? The belts do seem a bit loose.

                    Comment


                      Look on the hub pulley. Is there a strobe pattern printed on a white disk? Just watch in a room with (ideally) fluorescent lights. It should appear to stand still while the motor spins. Most likely it will appear to move forward or backward slowly. You can then adjust a pot on the board in the drive cabinet as detailed in the manual you posted the link for to make the pattern stand still.

                      Mike

                      Comment


                        Originally posted by nullvalue View Post
                        However, I am unable to boot from it using the 'B' monitor command. The disk drive engages but just spins and nothing happens.
                        The manual you posted has the connector information so you can know for sure in future.

                        If PCFLOP was able to write and verify the disk, then it should boot unless you have RAM problems. Use the monitor to test RAM from 0000 to DFFF and let it run for a while.

                        Mike

                        Comment


                          Originally posted by deramp5113 View Post
                          The manual you posted has the connector information so you can know for sure in future.

                          If PCFLOP was able to write and verify the disk, then it should boot unless you have RAM problems. Use the monitor to test RAM from 0000 to DFFF and let it run for a while.

                          Mike
                          Yes, very odd that I could run the disk creation but that I couldn't boot. How long does boot from disk typically take? Just a few seconds, right?

                          I let the memory test run for over an hour. From what I can tell, I got 0 failures: 20200524_095448.jpg

                          Yes there is a white disk with a strobe pattern. I will attempt the speed test.

                          Comment


                            So I put the drive under florescent light and attempted the speed test. There is just a blur of the wheel, no appearance of a slow spin or standing still. I adjusted the pot (tried both the top and bottom) and no adjustment seemed to make any difference whatsoever.

                            Comment


                              It has to be a 'real' oldskool fluorescent, not a newfangled compact fluorescent (CFL) bulb, or you could try an LED powered from a low-voltage AC power brick through a resistor.

                              Comment


                                You can pick out the pattern even with an incandescent bulb. Not as obvious as fluorescent, but it’s there.

                                Mike

                                Comment

                                Working...
                                X