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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.
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1MB on XT Macine

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  • Chuck(G)
    replied
    Yup, I believe that the PC7000's display appears as CGA, so you don't need to reserve the monochrome display area.
    Last edited by Chuck(G); July 31, 2018, 09:38 PM.

    Leave a comment:


  • MrArgent
    replied
    Originally posted by Chuck(G) View Post
    Sure, there were even one or two "almost PC" clones that populated the space between 0xA0000 and 0xB0000 with RAM giving 704K--and a couple "not even PC-ish" that used almost the entire 1MB space for RAM (video was handled by serial I/O). There's no absolute reason for 640KB other than IBM's convention. Plain MS-DOS runs fine on any of these.
    I'm not sure how, but the Sharp PC 7000 can take up to 720k of conventional fully upgraded...at least, mine reports 720k installed and usable.

    Leave a comment:


  • dieymir
    replied
    You can use USE!UMBS and DOSMAX to load PC/MS-DOS 5 or higher into upper memory. DR DOS 5 or higher it's more flexible, it lets you load the kernel into HMA or UMBs using HIDOS.SYS (HIMEM.SYS in Novell/DR DOS 7). DR DOS 6.0 HIDOS.SYS can create UMBs if you have an EMS 4.0 card. To use real RAM at "upper" addresses I think you need DR DOS 7 HIMEM (they renamed HIDOS) but AFAIK it needs a 286:

    HIMEM
    The HIMEM memory manager provides access to the upper memory area. The features provided by HIMEM, however, will depend on your hardware. If you are using a 286-based computer with extended memory, the only HIMEM feature you may be able to use is relocation of the DOS software to high memory. If you have a chip set or expanded memory board, you can use other HIMEM features.

    Use HIMEM if your computer is 80286-based. Also use HIMEM if you are using a pre-386 machine that has any of the following:

    A chip set such as Chips and Technologies NeAT* or NeATsx*, LeAPSet* or LeAPSetsx*, and SCAT*
    An EMS or EEMS expanded memory board and driver
    Permanent upper RAM
    [ ... ]
    The full syntax of the HIMEM DEVICE statement is as follows:

    DEVICE = C:\DRDOS\HIMEM.SYS /CHIPSET=AUTO|chipset|NONE

    [ ... ]

    You can specify any of the following as chipset:

    AM286ZX

    For Advanced Micro Devices Am286ZX/LX chip set.

    EMSALL

    For all EMS upper memory, including the page frame. This option disables use of EMS by all other programs.

    EMSUMB

    For EMS 4.0 or EEMS upper memory blocks. An EMS 4.0 or EEMS memory manager must also be loaded before HIMEM.

    HEDAKA

    For Ever-Success HEDAKA D60 chipset.

    NEAT

    For Chips and Technologies NeAT, NeATsx, LeAPSet, or LeAPSetsx chip set.

    RAM

    For permanent upper RAM. You must also use the /USE option to define the location of the RAM to HIMEM; see "Making an Area of Upper Memory Available (EMM386 and HIMEM)" on page 10-21.

    SCAT

    For Chips and Technologies SCAT chip set.

    Leave a comment:


  • Stone
    replied
    UMBs on an 8088:

    http://www.vcfed.org/forum/showthrea...driver-for-XTs

    Leave a comment:


  • SomeGuy
    replied
    A while back someone had mentioned that it was possible to load DOS 5 in to an upper memory block on an 8088 similar to how it is loaded in to HMA on a 286. Of course that assumes an add on card or motherboard modification is mapping RAM in the upper memory area. Never tried that myself, and usually DOS 3.3 or 3.31 is a better fit for an 8088/8086 class machine anyway.

    Practically speaking, loading a mouse driver, part of a network stack, or resident utilities in to an upper memory block can sometimes be handy while keeping conventional 640k free for applications.

    Leave a comment:


  • Chuck(G)
    replied
    Sure, there were even one or two "almost PC" clones that populated the space between 0xA0000 and 0xB0000 with RAM giving 704K--and a couple "not even PC-ish" that used almost the entire 1MB space for RAM (video was handled by serial I/O). There's no absolute reason for 640KB other than IBM's convention. Plain MS-DOS runs fine on any of these.

    Leave a comment:


  • Stone
    replied
    I have a card with software that can extend DOS, reach to either 704K or even 896K:

    http://www.vcfed.org/forum/showthrea...Expansion-card

    http://www.vcfed.org/forum/showthrea...-card-for-5170

    Leave a comment:


  • krebizfan
    replied
    Some software did have the ability to map extra memory into the 640k-704k region at the cost of not being able to use EGA or VGA graphics. It was beneficial for Desqview and DOS databases.

    Leave a comment:


  • Trixter
    replied
    Originally posted by Stone View Post
    Hmmmmmmm...
    Okay, I should backtrack on that one, given that he just restored a 3270 PC. No disrespect meant. What I meant was "novice in this area". Generally, anyone asking "is 640k the maximum your computer will use" is generally not prepared for the answer, either in configuration effort or in tracking down software that might actually use more than 640k via any means.

    Leave a comment:


  • Chuck(G)
    replied
    Well, now you have your answer.

    The need for more RAM was largely due to the popularity of Lotus 1-2-3 on the PC XT. Handling large spreadsheets by paging to slow hard disk was a real bottleneck. The best way was to use an EMS card, originally called "LIM" for the "Lotus/Intel/Microsoft specification". Other applications used it as well. For example, I've got an XT with an Intel Aboveboard 2MB installed and much of the MSLANMAN networking software will install in the EMS memory.

    Leave a comment:


  • willmurray461
    replied
    I don't need 1MB of RAM. I was just curious if it had any practical applications since I had an extra RAM expansion card lying around.

    Leave a comment:


  • ibmapc
    replied
    This Thread is an excellent write up for the 1 Meg XT Mod. that Chuck(G) referenced in his "chestnut" written by forum member pcdata76. It is still somewhat involved, but pcdata76 makes it pretty clear without needing to read through the entire thread that I started years ago.

    If you are serious about this mod, I can provide a programmed GAL.

    Greg

    Leave a comment:


  • Stone
    replied
    Originally posted by Trixter View Post
    True, but I wrote additional hardware, and chestnut requires a hardware mod. These are out of the realm of novices, which the OP's question betrays him as.
    Hmmmmmmm...

    Leave a comment:


  • Trixter
    replied
    True, but I wrote additional hardware, and chestnut requires a hardware mod. These are out of the realm of novices, which the OP's question betrays him as.

    Leave a comment:


  • Chuck(G)
    replied
    Also see chestnut. Doesn't require additional boards in a 5160.

    Leave a comment:

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