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

Apple IIGS Floppy Drive Weirdness

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

  • HoJoPo
    replied
    Originally posted by gsteemso View Post
    I vaguely recall reading something about defective VGC chip revisions, too—they could be discerned by certain ranges of the numbers stamped on the top. Did the defect affect floppy control? No idea, but possibly worth looking up.
    Unless someone did something dodgy, if it's a ROM 01 system, it should have the fixed VGC as well as the ROM 01 PROM. Apple shipped them as a kit together...

    The VGC problem had to do with pink fringes around DHGR monochrome graphics, if I recall correctly. Not an issue with the floppy controller I/O.

    Leave a comment:


  • gsteemso
    replied
    I vaguely recall reading something about defective VGC chip revisions, too—they could be discerned by certain ranges of the numbers stamped on the top. Did the defect affect floppy control? No idea, but possibly worth looking up.

    Leave a comment:


  • Rick Thornquist
    replied
    Larry -

    I don't have a scope, yet, but it's something to try when I get one.

    I was looking at the IWM and it doesn't look easy to replace. I can't find anywhere to buy a replacement, so that fact that I can't replace it may not matter!

    Swapping the VGC is certainly possible - it is socketed. I'll give that a try.

    - Rick

    Leave a comment:


  • retrogear
    replied
    >Here's a interesting new wrinkle. I tried attaching a 3 1/2" drive, the Apple 3.5 Drive (A9M0106), and booting GS/OS 6.0 off of a 3 1/2" disk. It booted fine! I then daisy chained a 5 1/4" drive off of it. With >nothing in the 5 1/4" drive I booted it up. The 5 1/4" drive was accessed, the drive clicks and the light goes on. It boots fine off of the 3 1/2" disk. But there's no 5 1/4" drive on the desktop! Huh?

    There is a different part# of 5.25 drive listed for the //gs and you have the correct ones. I'm guessing those //gs drives have special lines to detect presence for the smartport.
    Looking again at the //gs schematic, there are select lines running to the floppy connector from the VGC chip !! The VGC might be socketed if you want to try a swap ...

    Larry G

    Leave a comment:


  • retrogear
    replied
    The only way I see to proceed on this since you apparently have another //gs and 5.25 drive is with a scope to do side by side comparison of identical functions walking around the pins of the IWM but is it worth it?
    The concern would be one slip of a scope probe on the good machine could be disastrous. And even if you determine the chip is bad, is it even available or replaceable? I used to change postage stamp IC's with
    a butane pen to heat the old chip leads and lift it. Chips were sometimes also glued down so I had to heat the body enough to melt it. It pretty much destroys the old chip. There were square tips for irons to do the
    desoldering but they were expensive and custom sized plus if glued, just couldn't heat enough to melt. The butane pen worked well with just a continuous circling of the chip. That's my experience, anyway ...

    Larry G

    Leave a comment:


  • bear
    replied
    FWIW I had this exact same problem with an SE/30 twenty years ago. I replaced the system logic board.

    Leave a comment:


  • HoJoPo
    replied
    Originally posted by retrogear View Post

    PS - I have the hardware to test mixing the onboard 3.5 with a 820-5003-A 19 pin controller. Is it a safe idea to try this? I have an A9M0107 drive like yours but this controller is used with my A9M0104 drives
    Such a mix of combinations but good information, I suppose. I'm learning just by reading up on all the "stuff" I have ...

    Larry G
    Shouldn't be a problem to run the Apple II 5.25 controller in slot 6 (set to "Your Card" in the control panel) and use the built-in port on slot 5 for 3.5 drives. My developer seed prototype IIgs (aka IIBF) had a disk ][ controller in slot 6 and disk ][ drives when I received it, they worked with no problems, and a 3.5 drive on the built-in port worked fine at the same time.

    Leave a comment:


  • george
    replied
    Originally posted by KC9UDX View Post
    Are you sure? I thought write protection was handled in software or firmware. I seem to remember being able to write to write-protected disks. But maybe that wasn't on the Apple.
    Absolutely. What you seem to remember wasn't on Apples, and wasn't on PCs...You are able to write to WP diskettes if the drive is modified to ignore its write protection sensor. WP is indeed handled by software but cannot be overriden by software.

    Leave a comment:


  • retrogear
    replied
    >I'm thinking I could get an Apple 5.25 Controller and stick it in slot 6. Then I could run the 3 1/2" drives from the internal floppy port and the 5 1/4" drives from the card. Does that sound possible?
    One thing that concerns me is if the problem IS the IWM chip and the failure progresses, the 3.5 could fail eventually? You might be better off finding a controller for both 3.5 and 5.25 but probably rare.

    PS - I have the hardware to test mixing the onboard 3.5 with a 820-5003-A 19 pin controller. Is it a safe idea to try this? I have an A9M0107 drive like yours but this controller is used with my A9M0104 drives
    Such a mix of combinations but good information, I suppose. I'm learning just by reading up on all the "stuff" I have ...

    Larry G

    Leave a comment:


  • barrym95838
    replied
    Originally posted by retrogear View Post
    ... If you swapped cables too then sure seems like IWM chip is bad ...
    Larry G
    Agreed.

    Mike B.

    Leave a comment:


  • KC9UDX
    replied
    Originally posted by SomeGuy View Post
    Will those work with 3.5" IIc/IIGS/Laser 128 drives? (I can't quite remember)
    Yes.

    It seems to me there is one drive that won't work with it but it is a rare, unobtainable one. My memory could be way off on that one though.

    Leave a comment:


  • Rick Thornquist
    replied
    I'm thinking I could get an Apple 5.25 Controller and stick it in slot 6. Then I could run the 3 1/2" drives from the internal floppy port and the 5 1/4" drives from the card. Does that sound possible?

    Edit: Oops, I see Larry already suggested this. The Apple 5.25 Controller actually uses a 19 pin D connector instead of the ribbon connector so it should work with my 5 1/4" drive.

    The Apple 5.25 Controller cards seems to be pretty plentiful and cheap (except for the shipping to Canada - Arg!). It might be worth a try.

    -Rick

    Leave a comment:


  • SomeGuy
    replied
    Originally posted by KC9UDX View Post
    Not if you get a card from a Platinum //e.
    Will those work with 3.5" IIc/IIGS/Laser 128 drives? (I can't quite remember)

    Leave a comment:


  • KC9UDX
    replied
    Not if you get a card from a Platinum //e.

    Leave a comment:


  • retrogear
    replied
    > I think this has to be a motherboard thing.
    Well, then we're back to the IWM chip which controls both kinds of drives. Probably not much can be done w/o a new motherboard.
    I did read something interesting that whenever a motor on port is accessed on the 5.25 drive that the cpu speed is slowed from 2.8MHz to 1 MHz.
    Makes me wonder what it would do to a disk if it failed to reduce speed. Like a 5.25 drive on steroids

    PS - I suppose you could change in the control panel slot 6 to your card and add a Disk II controller but then you would need the ribbon cable type of drives.

    Larry G
    Last edited by retrogear; January 2, 2016, 10:30 PM.

    Leave a comment:

Working...
X