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

The Eagle 1600 computer

  • Filter
  • Time
  • Show
Clear All
new posts


    Eagle Computer.jpg

    I've got this one. It doesn't quite match the description you've written, so maybe it's for the later Eagle PC, or perhaps since it's Rev E, it's just a little different. It seems to have DOS 3.x on it.


      Very interesting, but this is indeed for the Eagle PC, Eagle Turbo, Spirit, and PC-Plus.

      It actually has Eagle MS-DOS 2.1, but someone copied a mis-matched PC-DOS on to it.

      The hard disk tools don't mention any support for the 1600 or the SASI card. But when I get a chance I'll give it a try. The hard drive init program included with their regular MS-DOS 2.x disks didn't recognize the SASI.

      It does include a graphics test program for their monochrome graphics card.


        Ok, so I went ahead and tested it on my Eagle 1600. As I suspected, it completely does not recognize the SASI system. It just acts as if it can't find a controller to communicate with.

        One interesting thing, though, that monochrome graphics test program completely does not work with Hercules mono graphics compatible cards. That tells me, as I suspected, that their monographics cards are not Hercules compatible. They should, however, work normally as a text-only MDA card with any other system. Unfortunately, the Eagle mono card I got with the 1600 was dead.


          It was my impression that the 1600 wasn't really PC-compatible. Even the floppy format is different 5x1024 bytes/sector/track instead of 9/512 per track. At least that's what my samples say.
          Reach me: vcfblackhole _at_ protonmail dot com.


            Originally posted by Chuck(G) View Post
            It was my impression that the 1600 wasn't really PC-compatible. Even the floppy format is different 5x1024 bytes/sector/track instead of 9/512 per track. At least that's what my samples say.
            It *attempts* IBM PC compatiblity. For example, interrupt and DMA resources on the motherboard appear the same. It can boot IBM PC-DOS from a 360k disk, and I have even been able to run Microsoft flight simulator II using a CGA card, although it doesn't display quite right. It can physically accept IBM PC ISA cards.

            But their choices of I/O devices are problematic.

            Although the quad density drive double steps for 360k media, writing media is problematic as in 1.2mb drives.

            Software for the Eagle 1600 did come on their ~800k quad density disks, and that is what it tries to use by default.

            Programs that directly access the FDC don't like the controller. The serial and parallel I/O cards are very strange. The SASI system is nothing like IBM PC controllers, and support for it is built in to the 1600 motherboard ROM. Programs that write directly to the screen will work, but as it turns out, their mono graphics cards is not compatible with Hercules.

            The big problem I have with it is that word-sized reads and writes to the ISA bus appear to fail while byte sized reads and writes work. I have no idea if this is a problem with just mine since no one else has a 1600 for me to compare this to. Since most resources seem to use byte sized communication, it still boots and works, but programs that write words to the the video, such as Microsoft flight simulator 2, only show every other byte on the screen. I have a hard time believing this is a design flaw, as even the BIOS does word access - to detect the signature of ISA expansion ROMs, which seems to be why detection fails.

            There had been one other Eagle 1600 on eBay a few years back, but they wanted too much for it. It never did sell, and then just disappeared.


              The lack of word access to ISA 8-bit cards figures. The 1600 used the 8086 with a 16-bit bus and simply ignored the half of the word on I/O to the ISA bus. On the PC, the 8088 BIU takes care of that issue. The Olivetti M24/6300 has a rather complex bit of logic to create two byte accesses from a word I/O operation. I have no idea if the other 8086-based "almost PC" boxes, such as the Stearns, suffered similar issues.
              Reach me: vcfblackhole _at_ protonmail dot com.


                I'd still like to know for absolutely sure if this is or isn't just a malfunction on my machine.

                Does anyone have schematics? I've been meaning to try and trace things out manually and compare the Eagle 1600 to M24/6300 schematics, although I don't doubt the two are vastly different.