I don't mean to sound discouraging, Jake. But I don't even know where to begin.

I mean, King's Quest can only go so fast. 😖 and only takes up a neglible fraction of a 4.5GB drive. 😦

You've got some awesome spare hardware laying there. And a lot of it IS apropos for what you're doing. But some of it is just off-the-wall for a 286.

It would be a shame to have that hardware locked up in a 286 when you'd get a lot more use out of it if you saved it for a relatively newer system.

Just my 2cents.

I like it! 😀
Of course it's not like a typical XT clone, but the "hot-rod" approach sounds fun.
And some of the hardware does make a lot of sense if you want to use the machine on a daily basis. The SCSI drive for example is a good idea, it should be a lot more reliable than the typical MFM or RLL disk. The EMS board doesn't get used by a lot of software, but it would be handy for a RAMDisk.

jake_friz wrote:

There has to be a way to get memory into the upper memory space. I have an old shareware app that will loadhigh on an 8088. I found a howto for an XT to get UMBs installed. How do i get memory into that space on my clone?

I depends on your hardware. Some XT clone boards had the possibility to add more than 640k in order to shadow ROM space for more speed. There also were ISA memory cards that could map memory above the 640k. I'm not sure if your mainboard or the Intel Above Board can pull off this trick.

Other thoughts: The VGA cards you have available are OK, but I'd recommend a Tseng ET4000 (as usual 🤣) because it emulates older standards very well. This is a 16-bit ISA card, but it will work as well in 8-bit slots (if cou can fit it in mechanically).

About the non-working CD-ROM and game controller: Perhaps a SoundBlaster Pro 2.0 would do the trick. It supports Panasonic CDROM drives and has a gameport that usually works.

I managed to get Minix 2.0.2 nearly running on this system. I still need to copy the USR files and source code and then compile in the NIC driver. Its boot loader works great for selecting a specific partition to boot from so I can dual boot Minix and DOS.

I added a SB Pro 2.0 as well. The game port works great. I have a gravis PC GamePad running from it.

I gave FreeDOS a try. It ran but was noticably slower than MS-DOS 6.22 so I went back to MS.

And I changed video cards to a Sigma Designs VGA card with a TSENG Labs ET3000AX chip on it. Thanks for the advice on the TSENG 4000, I just happen to have one of those. I'll give it a try.

Lastly I just got a copy of Star Flight and I'm itching to start playing.

hello
I am also doing XT mods, and tuning them to the max.
Spare parts and a machine:
v20,8087,100NsRAM
sound blaster (8bit)
2 times intel above 2Mbyte
3com network card
tseng4000 (16bit) , have any got it working with windows ??
and in reply to your question....
I use a "Data technology corporation" "DTC-406" scsi interface
AND got a DVD-r reading going (drive: HP a5220). CDrw also at hand - writing not testet. 😀

So little time so many tings to test...
..but some day I am gonna test:
software: VNC , RDP, minix, windows, internet, more RAM twaeks
hardware: IBM exp300 scsi-rack !! ,and IF I find one i286 / i386 card ..
...(have Soda i286 ..no doc's - not working 😖 )
/Cimonvg

You really brought this post back from the dead, eh?

Your proposed XT looks pretty nice, but I really have to say "good luck" writing DVDs on an XT. Is it possible to get FAT32 partitions going on an 808x type machine? I haven't tried it yet. All I know is with FAT16 partition sizes are limited to just 2GB. I don't believe it is possible to partition a DVD either. Anyway, you might as well give it a shot. I've done some pretty nutty stuff with my XT that some were skeptical about too.

My XT is pretty much always under construction, but here's what I have so far:

-Juko 15MHz V30 motherboard
-1MB 60ns DRAM (640kb active)
-Orchid Ramquest 8/16 w/32MB DRAM (LIM 4.0)
-ATi VGAWonder w/512kb DRAM (digital & analog output, bus mouse)
-Intel Etherexpress 8/16 10mbps NIC
-Sound Blaster Pro 2.0
-Future Domain TMC-850M SCSI
-Acard 7722U SCSI --> IDE bridge adapter
-2GB Compact Flash (Sandisk Ultra II, externally accessable)
-1080MB 5400RPM IBM SCSI HDD
-IBM/Plextor 8X SCSI CD-ROM
-IBM 360k & 1.44meg FDD
-IBM 5151 Display & 101-key XT keyboard
-IBM 5160 Chassis

However, there are a few issues I still need to take care of. I am not able to run an 8087 FPU because I can't find one that runs at 15MHz. This really pisses me off. I have explored adapting an 80287 to the 8087 socket, but it's really not trivial. I'm going to try anyway though.
I also want to replace my motherboard's DRAM with SRAM at some point. A couple of PCjr users did this, and supposedly on the PCjr there is a pretty noticeable improvement.
I currently run my 1.44meg drive on a high density controller, but I found a software application that can do the same thing, so I might remove it.
I heard that there is a version of AWARD BIOS for the XT that has built in support for HD floppy drives an 101-key keyboards. I want a copy of this.
There are some people that run SB16s and Mach64s in their XTs, but I think that's a little too crazy.

Let me know if you need any help with your build.

To clarify , a have a DVD-rom (hp a5220) and a CD-rw (teac cd-r55s), but the SCSI card "dtc406" only supports one MO-drive....

At first , I did find it the most fun modding the XT with spare parts older then 1990. But now I think - IF it is going to make any juse there has to be some new parts aswell. SB16.. have to try that one some day 😀

The -floppy reader- software you at talking about . Is it some small free/gnu thing ?

FAT32 read/write software: Perhaps Freedos has this feature ?

I'm not familiar with DTC SCSI controller. Does it use a common chipset? I know of Future Domain (seagate also), NCR and Rancho. I like Future Domains. They have really good device support. Did you say you have magneto optical drives? By any chance would you happen to have a copy of Corel SCSI?

FreeDOS does indeed have FAT32 support, but I am not sure if it can work on an 808x. It probably needs a 286 or 386.

The floppy reader comes with "2M V3.0". The program is mainly for formatting 1.44meg disks at higher capacities, but also includes special TSRs for high density drives in XT and AT systems. If you want to run it on an XT you need a floppy controller that supports the faster spindle speeds. My XT uses an AT multi i/o in 8-bit mode. The 2M documentation recommends this.

hey
dont think i have corel scsi.

Connectet a AT keyboard to my Phoenix BIOS 2.27b. Worked fine , but 3 boot's later the screen just said "Bad keyboard" 😖
Think the keboard's were defective(?). I give it at try some other day with another keyboard.

Correction: my scsi called : Data techonology corporation "3250" rev 1.
with a floppy-chip DTC-403/4 and scsi DTC-406 chip.

Looking forward , trying my "new" Sota i386sx card 😁

Going to look for a Orchid Ramquest 8/16 .. seems like a fine product. Or ?

When having time - going to try an old "CardPort ex" LPT->PCMCIA interface 😎
-CimonVG

The RAMquests can be difficult to find on eBay. I think the main problem is that there is no marking on the board whatsoever to identify the model name or the manufacturer. So, you need to know what the board looks like. Basically a full length card with 8 30pin RAM slots at the end with a single large Xilinx chip at the other end of the card.

What kind of interesting features are included with Phoenix BIOS 2.27b?

hello again
Just tried the Sota 386si , and it seems to work. 😀
(at the moment -without softwaredrivers- not running faster then the V20 🤣 )
Wonder if any did a driver mappning EMS / XMS from i386 over 8bit isa to a 16 isa memory board ?? 😮
..in other words - a have to look for a "SOTA Memory /16i" , if any exists.
Giving opportunity to run 386 software with internal 16 bit bus (sota 386si<->memory/16i).

How do I see what functions a specific BIOS supports ??
..dont know any advantage with the Phoenix BIOS - just funny with a still known manufacture.

8087-3 can't remember is it 12Mhz or faster ??
/Cimonvg

CimonVG wrote:

Wonder if any did a driver mappning EMS / XMS from i386 over 8bit isa to a 16 isa memory board ?? 😮

AST driver REMM.SYS has a parameter to make it work either as 16bit or 8bit in 128kB memory blocks
DEVICE=REMM.SYS /M=FF make it work as 16 bit
DEVICE=REMM.SYS /M=00 make it work as 8 bit
Actually /M parameter is a 16bit hex number whose bits designate which 128kB block you want the card communicate thought 16bit memory bus
It was primary intended to solve conflict between 8bit and 16bit memory mapped devices.

Memory on 8bit bus can't be mapped over 1MB, it can only be used as conventional and EMS memory

8087-3 is an alternate name for 5MHz 8087
8087 and 8087-3 = 5MHz
8087-2 = 8MHz
8087-1 = 10MHz

Yeah, no such thing as 12MHz 8087. Some people can get away with overclocking a 10MHz part, but it doesn't always work and probably requires heatsinks. Since I need a 15MHz part this likely won't work without peltier cooling.

I am actually not sure if there is anything particularly special about the Phoenix BIOS. What I do know is that supposedly the last versions of Phoenix and AWARD BIOS have special built in support for high density floppy and 101 keyboards. It would be pretty nice to get a ROM dump of either of those. The last version of Phoenix XT BIOS I am aware of is v2.52 (I believe there were also revisions of this BIOS identified by a letter at the end of the version number). I currently have a ROM dump of v2.51 but I haven't tested it out yet.

I think what CimonVG wants is 16-bit XMS memory rather than EMS. I think he's going to have to track down the SOTA memory expansion if he wants XMS.

Actually, there is really no reason why someone couldn't write a driver to have EMS memory emulate XMS memory. Infact, AST made such a driver in the late 1980s. I believe it is called REXX. Unfortunately it only provides XMS 1.0. I think any DOS application that actually uses XMS memory will require version 2.0 or 3.0.

For anonymous coward:

I have a couple of questions about your xt machine:

You use an acard ide to scsi bridge in the internal 50 pin
connector of the future domain, is it??
The plextor cdrom, and the ibm hdd are both external connected
at the 25 pin external db-25 of the future domain??? Please make
photos of the machine and the drives!!!

One more thing, do you have the drivers of the juko mainboard for the
ems???
I have a mainboard with 640kb+128kb of ems but i didn´t find any driver
for use this 128kb, any ideas??

About the acard ide to scsi bridge, I discoverd little time ago and really
is a incredible solution for using cf cards in any xt system.

I see that you use a sandisk 2gb extreme II cf, can I use the new extreme III models of 2gb,4gb and 8gb??? or the limit of msdos is 2gb???

Perhaps we can make a list of 100% running cf with this configuration.

One last thing, can you use more than a cf card in the ide cable, ej:
the cf & a ide cdrom or hd, or the acard is only limited for use 1 device ???

I hope you can solve all my questions,

Regards.

Here's a picture of my system:

The CF card is mounted on one of the backpanels and is not visible in this image. All of my drives are mounted internally on a Future Domain TMC850M. I have not tried multiple IDE drives on one ACARD, but according to the manaul you can only use one drive. That would make sense as you need a SCSI ID for each device, and the ACARD can only be configured for a single ID.

There do exist IDE to CF converters that allow you to run multiple CF cards on a single IDE port. I have not tried this and I am not sure how that work work with the ACARD. I figure it has a fair chance of working. You won't know until you try, but I had a hard enough time just getting one CF card going and I'm happy with it. DOS is limited to 2GB partitions, but you can have more than one partition if you need it. Personally I think 2GB flash + 1GB HDD +CD-ROM is super overkill in this machine.

I actually do have the software for the Juko motherboards but I do not have it with me. I have also never tried it before since I have a much better EMS ISA card. If you want the software there is a guy in the vintage-computers.com webforums that has it. I think his name is "the xt guy".

I hope that helps.

Hey
Just powered on my xt with sota 386si card WITH driver that enables internal cache on 386si. Wauu what a difference ! Now it is "fast" someting like 8 times xt speed!
And tried my floppy controller and it works fine as well.
Controller with chip "um8398" and bios "name - 4310". (made in taiwan r.o.c.) It boots old 5 1/4" and reads 3 1/2" 1.44Mb floppys as well 😀
But - strange, reading on my dvd-rom drive. Not possible to access all subfolders ? have to try some diffent drivers /mscdex some day !

And yes , fun if it existet - a driver that enables XMS over a 8 bit channel. (have to try REMM / AST some day).

and yes - have a magneto optical drive but it is broken ...

..so many thing to test so little time...
happy modding /Cimonvg

I the CPU performance is 8 times the speed of an XT, but if you're doing data transfers over the 8-bit external bus things are going to slow down quite a lot.

I have never tried using a DVD-ROM drive in DOS before, but wouldn't the 2GB partition limit of DOS cause problems with 4.7GB DVD-ROM media?

Also, I want to repeat a nifty little trick I posted over on vintage-computers.com. I discovered a way to load DOS into UMB memory on an XT, freeing up to 618kb conventional memory on my system. If you use a little program called Quarterdeck QRAM 2.0, you can load device drivers into UMB with a LIM 4.0 card. Stealing the LOADHI and DOSUP.SYS files from QEMM 8, you can stuff the DOS components into UMB as well. I think this trick may require a V20 CPU though, as I have not tested on an 8088.

hello
was looking for a ATI vga on ebay.
ATI 1090011541 Ultra A 16 cost 10$, and Ati Graphics Xpression Video Card go as low as 20$ - but only in US .... that leaves me out 😒
What about Ultra16 any good ??
PS. mach32 seemes to be a bit "expensive".

Will try FreeDos some day and try copying large files DVD->scsi.
..the other day tried copying scsi hd->scsi hd at a speed of 214kb/s..
/cimonvg

There's no such thing as an "ultra16". I looked up the number, and it's a "graphics ultra" based on the Mach8 chip. Those cards are okay, but what you really want for an XT is the original VGAWonder or VGAWonder 16. Those cards have 9-pin digital connectors which is great if you want to swap between MDA/CGA/EGA/VGA displays.

Your HD to HD transfer rate seems about right for an XT.

hey
just short note. Awaiting 2 jused boards 😁
ATI mach32 with 512k vram and a MegaLITH ISA 16-Bit 8MB !
- think it is something like Orchid Ramquest ? 😕
..time will tell.
merry christmas
/cimonvg