Forum 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.

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.

Stay close to the original topic being discussed
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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.
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"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:
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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.

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.
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Use a High Density FDD in an older PC

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    Use a High Density FDD in an older PC

    The original IBM PCs and XTs were made before High Density FDD's caught on, and as a result of this, no intentional support were added in neither hardware or software. In order to get HD drives to work on a PC or XT, we have to work around therse limitations.

    The original IBM Floppy disk controller was based around a simple microcontroller for controll and a bunch of custom logic for interfacing. This card was intended to be used with Double-Density drives, and it's unable to interface with HD drives due to timing issues (unless the HD drive emulates a DD drive when DD media is present). In order for the computer to properly interface with HD drives, the controller must be replaced with a more recent one with support for HD drives.
    Controllers as found on AT-style multifunction cards works well, as they mostly only use the 8-bit partion of the card's 16-bit bus. With a HD-compatible controller, the computer will at least be able to interface with HD drives.

    The next limitation is the BIOS. By default, the BIOS can't really make too much sense of more recent formats, even though it may be able to read and write correctly to DD disks of any size. HD disks may still be unreadable, and will in that case just generate errors when access is attempted. In order to solve this problem, a more recent replacement of the BIOS diskette routine package (Int 13h) must be installed.
    Some HD controllers come with a replacement in a physical ROM chip on the card itself. This replacement is automatically loaded on boot, and all you have to make sure is that the switches on the card are set correctly.
    If this is not the case, a replacement will have to be installed by a software driver after the machine boots, usually as a part of the OS initialization. An example of such a driver is '2M-XBIOS.COM' from the 2M FD-tool package[footnote][/footnote]. If the machine has an HDD, this will be no problem since the driver is not needed for the HDD to boot properly, but if the machine only has floppy drives, a startup disk of Double-Density has to be used in order to install the driver. This disk must of course be formated as a startup disk, and it must also contain the driver. You should make sure to read how to set up the driver before installing it (this information usually provided with the driver).
    The Vintage Computer and Gaming Marketplace
    The Vintage Computer

    I don't understand what "HD FDD" means. HD = "hard disk"; FDD = "floppy disk drive" or maybe "fixed disk drive"--the use of the two acronyms together is confusing. Why not just spell it out? "Hard Disk".

    "Fixed disk drive" once had a very specific meaning--a drive whose media could not be removed. The IBM 2314, for example, was not a fixed disk drive--the 2316 packs could be removed.


      high-density floppy disk drive.


        Okay, an Emily Latella moment.

        Nevertheless, "high denisty floppy drive" would clear up a bunch of headscratching.


          lol. agreed, yeah that would help.


            I would love a 3.5" drive in my 5160, I didn't want HD so much for the capacity, more because a) They are plentiful and cheap, b) they come in black(!) but I've never found a combination of drive / controller that actually works for me. Has anyone got one running in a 5160 and if so which card / drive?


              IIRC, a 1.44 floppy will function in a 5160 as a 720K floppy.
              PM me if you're looking for 3" or 5" floppy disks. EMail For everything else, Take Another Step


                Originally posted by circuit View Post
                I would love a 3.5" drive in my 5160, I didn't want HD so much for the capacity, more because a) They are plentiful and cheap, b) they come in black(!) but I've never found a combination of drive / controller that actually works for me. Has anyone got one running in a 5160 and if so which card / drive?
                An 8 bit ISA controller card that I have found works in a 5150 PC to install a 1.44 MB floppy disk drive is from JCC. Here is a listing to one on EBAY. (Keywords JCC 2DR14A 810730). I'm guessing you can find one for much less if you watch the listings and search on the keywords. FWITW: I have tried several floppy disk controllers in a 5150 that 'should' work, but don't!



                  Ouch!, Way too expensive and missing the HD floppy bios Rom.


                    As 'Stone' said, A 1.44M Floppy drive will function in an XT 5160 as a 720K connected to the original controller, See This Page on Modem7's website.

                    Originally posted by circuit View Post
                    I would love a 3.5" drive in my 5160, I didn't want HD so much for the capacity, more because a) They are plentiful and cheap, b) they come in black(!) but I've never found a combination of drive / controller that actually works for me. Has anyone got one running in a 5160 and if so which card / drive?


                      I built one of these. It works great in my 5150, and can even read and write single density TRS-80 disks!

                      -----[ Al ]-----

                      3 - TRS-80 Model I, TRS-80 Model 4D, LNW-80 Model I, Coco, 3 - Coco 2, Coco 3, 2 - Tano Dragon 64, C64, C64c, C128, 2 - Atari 800XL,
                      Atari 520-ST, Atari Mega-2 ST, Amiga 1000, TS-1000, TS-2068, ZX-Spectrum, IBM 5150, 2 - Apple ][gs, Laser 128, and a butt load of Macs and Intel PCs.