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wierd_w

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Posts posted by wierd_w

  1. 9 hours ago, LostCause said:

    It is extremely refreshing to my soul that you have taken the time to examine the sub. You, and hopefully others could be my inspiration to complete this game. I have DOS and drivers loaded in high memory, not much left there. I have close to the full 640k conventional memory free, if QBasic can utilize that, waits to be explored. I hope this becomes a development thread for the game. Interested, stay tuned.

     

    After my last post, I suspected the multiplication was evaluated as a signed word before being cast. The first tmpvar assignment is meant to strip the high word value and dividing by 65536 to convert to word value. The if – end if clause assigns the signed dword value to the signed word based on whether it should be passed as a positive integer or twos compliment. I can see already that instead if dividing by 65536 that the bit shift operator may have been a better choice. If that will work.

     

     

    Disk space is cheap. BSAVE and BLOAD can be used on arbitrary data contained inside of arrays. This allows it to be used with custom types, etc, and thus can be used for slow disk paging of entire memory structures.

     

    640k is only really limiting in terms of the size of the array.  

     

    Even then, it is possible to directly hook and prod at XMS memory, if it is available, by writing to the appropriate handlers. (Initiating calls with io requests, with data in registers, et al.)

     

    What qbasic lacks is an efficient bulk memory copy routine.

     

    Writing one as an assembler stub, then executing it after pulling it into memory, and wrapping that invocation in a sub statement should do the trick though.

  2. After putting the mrchromebox uefi firmware, yes.

     

    Out of the box, no.

     

    You would need to put it into 'developer mode', then run the firmware installer script from a crosh shell.  After that, it would have coreboot uefi, and be able to run any uefi capable OS. (Windows 10+ included, but may need stuff from coolstar to run properly. Win7 is not truly uefi. Needs a CSM, and coreboot from mrchromebox does not have one.)

     

    You would need to open the lid and remove the write protect screw before flashing with the install script.

     

    It would basically be a 'fully FOSSed' NUC after that.

     

    That particular one is reasonably upgradable even.  Note that it has an NGFF SSD, and SODIMM RAM.

     

    FT7H1USIQU11VS5.jpg?auto=webp&fit=bounds

  3. 7 hours ago, Keatah said:

    Suddenly the job became 10x easier. They're interested in those pissy mini-consoles and flashbacks.

    If they want a pretty set-top box, Get and recondition (with mrchromebox uefi) a chromeBox.

     

    Its about the same thing as a NUC, but much less expensive.

     

    Here's one on fleabay for 70$. I7 with 8gb ram. MORE than beefy enough. They could do all the way up to wii/wii-u on that.

     

     

    EmulationStation would work fine.

  4. 1 hour ago, Keatah said:

    But more-than-capable PCs are in the $500-600 range, new. Used or off-lease are cheaper.

     

     

    Cheaper!

    If you dont mind a little ear pulling, you can transform a weak-kneed chromebook into a very nice emulation platform.

    100$ pricepoint is VERY doable.  (check out mrchromebox.tech, for details! Getting a "Real" UEFI firmware on that 100$ POS is quite doable!)

    It is more than powerful enough to doe UAE, ST emulation, DosBox, and pals.  EmulationStation on it would be quite doable.

    • Thanks 1
  5. I have a vintage parallel port zip100 which still works fine, but that was a 'new in box' purchase from 30 years ago. Mine has the connector for 'not really scsi' so it could live quite a few places, in theory.

     

    It's slow as hell, but was useful awhile back for getting stuff on my dos gaming retro laptop.

     

    Otherwise no. I dont collect. I have considered the amusing chic of rebuilding some apple or sun scsi enclosures and slapping them on a nas box, but decided that's a waste of vintage gear.

    • Like 1
  6. From what I was reading use-umbs is the proper tool, and can accept different ranges, despite what I read in the readme.

     

    I did some digging.

     

    This core emulates a lo-tech 2mb ems board, with a pageframe address of a000.

     

    MSD is not properly detecting a ROM at EC00, according to what I am reading. Probably is not setting the memory read only.

     

    The author suggests the following in this post.

     

     

    FILES=40 BUFFERS = 30 DOS = HIGH, UMB DEVICE=C:\UTIL\USE!UMBS.SYS C000-EC00 DEVICE=C:\UTIL\DOSMAX\DOSMAX.EXE /R+ /N+ /P- DEVICEHIGH=C:\UTIL\LTEMM.EXE /p:A000 /x /n SHELL=C:\UTIL\DOSMAX\SHELLMAX.COM C:\COMMAND.COM C:\ /E:256 /P

     

     

    It may be possible to enable more upper memory, but I need to know how big the xt-ide bios at EC00 is.

     

    MSD should detect the option rom in the other memory viewer pages, and say how large it is. I think it's "memory browser" or something like that. Been awhile.  This is because option roms contain a magic header byte sequence identifying the option rom and its size, and MSD is designed to scan for this, even if the memory is writable.

     

    Normally, I would test and experiment myself, but the de10-nano needed to build a mister is too expensive.

     

     

     

    • Thanks 1
  7. I am a fan of Direct Access 5.  It DOES work on XTs.

     

    It supports submenus. (I have never found a functional bottom to how deep it can nest.)

     

    https://winworldpc.com/product/direct-access/5x

     

    (I use it to get around the restrictions on the free version of adosbox on android. It limits to one application-- phht-- OK, I will set up DA5, and then pick from there!)

     

    It has a few nice features, in that it returns to the menu once you quit your game/application. 

    • Like 3
  8. You have the entire adapter rom region free, and backed with RAM!

     

    Consider a different enabler that accepts an argument for the regions to enable. The one you are driving now has a readme saying you have to manually patch the program to change the target region.

     

    It looks like you could use between C000 and EBFF.  That's a big area.

     

    The core does not emulate extended memory, but some old games can use expanded (ems) memory.

     

    There's a DOS driver that can live in upper memory that can provide it via what is essentially a swapfile.

     

    Found it.

     

    https://www.vogonsdrivers.com/getfile.php?fileid=851&menustate=0

     

    EMS memory would be 'slow', because it is fetched from disk, but games that use it would have it available. (It's normally provided by a hardware ram card with a mapper chip)

     

    DOSMAX would be a good choice here also, since we have ample ram-backed area to work with. It can load files, buffers, fcbs, and the command interpreter into UMB.  You can realistically have over 600k free.

     

     

     

  9. This is an XT class machine, so it wont have more than 640k. (though it looks like you are using a memory manager to enable hardware UMBs in the adapter region... So we can TRY to maximize what is enabled/used. MSD with nothing loaded, not even the enabler, will let me see what areas are consumed by ROM.)

    Normally, there might only be some small benefit from altering the load order, since XTs normally cannot load anything high. In this case though... Yeah, let's see what we have to work with, and what we can get it to do.

     

    If this is a 386 class machine with extended memory, then I need to see what your memory map looks like with nothing loaded. DOS 6.22 comes with a utility called MSD.  It will let me see what I need to see.  Since this is with a MiSTer, take a screenshot with it running showing the memory map for me, and post it here, then we can discuss what memory managers you want to use, and how to prod it good.

    • Like 1
  10. 23 hours ago, youxia said:

    Alright, thanks. I will give it a go. I think I did fdisk /mbr before but not sure.

     

    I'm still after these separate 250, 500 and 1GB disks, if you can be bothered ;)

     

     


    OK, I will make some.  These are not perfect sizes, because of a bug in DOS that prevents full use of 256 heads and or 1024 cylinders, for sizes. Closest matches provided, for max compatibility.
    They should be bootable with minimal system DOS 6.22.  They were created with dosbox, because it is just faster than manually prodding vmdk files for virtualbox, but I did test booting them with dosbox.

     

    254.75mb (267125760 bytes) disk

    256mb.img.7z

    Single partition, 4k cluster

    512 bytes/sector
    1023 cylinders
    255 heads
    2 sectors/track

     


    510mb (536870912 bytes) disk:

    512mb.img.7z

    Single partition, 8k cluster

    512 bytes/sector
    1023 cylinders
    255 heads
    4 sectors/track

     

     

    1019mb (1068503040 bytes) disk:

    1024mb.img.7z

    Single partition, 16k cluster

    512 bytes/sector
    1023 cylinders
    255 heads
    8 sectors/track

    • Thanks 1
  11. OK. Here is a booting version of that 3 partition image.  Has Dos 6.22 installed, nothing else.  Same partition structure.

    2gb_3part.img.7z

     

    You can probably just fix the image you have by running

     

    FDISK /MBR

     

    on it, however.  Basically, the disk image lacks a boot loader in sector 0, since it was a 0-filled image. :P

    (I had to re-learn how to build VMDK header/descriptor files for flat images, so that I could feed it to virtualbox! LOL! Anyway, the issue seems to have been the missing MBR code. Running the magic fdisk command with that switch should fix it.)

     

    • Thanks 1
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