Well ..my project is currently on hold whilst I wait for yet another ESS sound card to arrive
an ES1868F...which hopefully will be easier to get drivers for..
Phil covered this one I believe in one of his 'lab' videos.
I also have a 3com dual connect ISA winging its way to me from a friend.
This will give me a BNC coax and Ethernet connection.
So really ..I'm now ready to install win 3.11
These 2 cards will complete the build and fill up all the ISA slots.
So ..I will have the first 8 bit slot holding the XT-IE card with a 64mb CF.
The second 8 bit slot has the Serial port card ..for mouse etc.
The first 16 bit slot holds the VGA card
the next 16 bit slot ..currently empty and waiting for the sound card..
Next slot holds an Adeptec SCSI card ..
The next holds the hard drive/floppy controller
The last slot being also empty and hopefully will be used for a network card.
Currently I have MS dos 6.22 on the CF ...and on the 100mb Conner ...but also on an 820mb scsi hard drive hooked to the adaptec.
Booting goes directly to the XT-IDE menu unless I press A: for floppy
I also have a 5.25" B: drive not yet hooked into the system.
Selecting any of those 3 hard drives allows me to boot and once in DOS can see and access either of the other 2 hard drives.
Thus I will have an easy way to get files in and out with the CF card ..plus more storage space on the SCSI ...as the Internal bios prevents adding anything larger than 100mb to the primary IDE controller card.
..or indeed the XTIDE bios...Only by going SCSI can I exceed this 100mb limit....unless I can find a more recent bios for the mobo.
I have replaced the fan in the PSU which was totally seized ...
Also hooked up the turbo switch ...
I think now that I have 4mb system/expanded ram win 3.11 is practical ..though may run a little slow.(please let me know if win 3.11 is not practical on a 286 ?)
All in all ..progress albeit slow is being made.
Now ..I have one 5.25 inch bay left ..and intend to fit a CD drive in it...
..but Have chosen to add a scsi CD drive...since the adaptec is already in there.
..and hopefully avoid any bios problems with the WG-GEAR bios this way....as control would be given to the adaptec card.
Anyhoo ..a couple of photos to be going on with.
..appologies for catching my cats litter tray in the last photo...but it did prompt me to clean it out...🤣

From what I understand, 3.11 will work, as will 3.1, but with more limited features than with a 386. Windows 3.0 has some additional features and modes available to the 286 but has stability issues directly tied to those features.

I've heard conflicting things about Real Mode and 286 Protected Mode support in 3.0 and 3.1x and haven't played around with it yet myself.

4MB is a pretty healthy amount of RAM for when those OSs were new, even 3.11 I think. The 12 MHz speed might make it a bit sluggish, but the benchmarks I did at 0 ws pointed to being fairly fast for that clock speed at least. (looks about as fast as a Headland HT12 board at the same speed and 0WS)

Additionally, I've had good luck with non-plug-n-play Sound Blaster Vibra 16S cards in testing my 286 boards. (using the vibra 16 installation utility on the vogons archive)

I haven't tried an ESS Audiodrive yet or any sound card based CD-ROM drivers.

I didn't think there was much issue between different board implementations of the Audiodrive using the same range of drivers, unless you've got actually different ESS chips on these boards.

Also no update on my 1212C. I haven't dumped the BIOS yet or messed with the RAM more. (on second thought, it could just be dirty/sensitive contacts on both the SIPP and DIP sockets and a coincidence that both managed to still work at 512kB base memory ... I'm not sure if the auto-detect mechanism used could also cause 512k+512k to be seen as 512+128k due to bad contact on some address lines, but maybe that's the case too)

If/when I do get the RAM working properly, I have some new SIPP sockets that should plug in nicely and I could try up to 16 MB in there. (just did that with my Hedaka 988 and it detected it properly after I swapped in a PCChips M209 BIOS spare I had, though backed it off to 8MB for now with 4MB set to XMS for now) Still doesn't like 24 or 25 MHz much (with 60 ns RAM) but doesn't mind 80 ns SIMMs at 20 MHz at least. (and I imagine 4MB XMS for DOS/Windows + 4MB base+EMS for single-task real-mode program execution should work out well)

If you get your hands on some 4MB SIMMs before I get my board working right, 8 or 16 MB in there sounds like fun, too. The EMS and XMS configuration seems pretty flexible with this chipset as well. (I've found Suntac's EMS support to be neat in some areas but limited in others: like having EMS enabled still leaves the 64kB of real-mode accessible HMA mapped so DOS can load high, but it doesn't seem to allow block of EMS or XMS memory to be configured as one or the other; good for games and single-tasking real-mode DOS stuff with EMS support with base memory freed up from DOS and limited total system RAM, and also potentially nice for overclocking CPUs that have stability issues in protected mode at lower speeds than in real mode)

But again, I want to backup/dump that BIOS before messing with it any more anyway.

http://www.vcfed.org/forum/showthread.php?575 … 2-286-BIOS-Save

This seems to be a bust (short of trying to contact the members there), but this looks promising:
http://mess.redump.net/dumping/dump_bios_using_debug

Lots of other references to dumping bios images via EPROM readers, but that's what I'm trying to avoid for the moment.

Thanks for the update KK ..
When it comes to dumping bios ...I prefer reading the chips directly with my TL866 or similar.
Usually readable as an eprom if totally pin compatible.

Still waiting for my ESS sound card ..which is due with todays post...but got to cut 'em some slack under the current crisis.
I'll press those links and take a look..
keep me in your loop and stay safe buddy..

Hey Kool Kitty ..
Is this you out shopping ??
If so ..much respect for taking the social distancing advice..

I am curious now about CPU speeds
Can I simply replace a 12 mhz PLCC 80286 with a say....16mhz version and perhaps change a crystal ...or is this too simplistic ??
Obviously I dont just want to try this without some advice first ?
rgds
VS

Yes go ahead, that is called underclocking and another benefit is cooler.

Take care with the socket. That socket's slots for tool to pull CPU out cracks easily if using levering method to pry out the CPU.

Cheers,

Thanks Pentium...for that speedy response..

Sadly still waiting for postal deliveries ..but will cut them some slack considering the crisis.
..note to self..must exercise a little patience.
Had to fit a different 5.25" floppy ...sadly the one I wanted to use ..a TEAC FD-55GFR appears to have faults on the servo board.
So took advantage of todays UK sunshine ..broke out the Hydrogen Peroxide ..and retrobrited a very old and yellowed YE DATA YD-380B.
along with the case front.
Both now look almost new..
but the YEdata disk latch knob was splitting and cracking..
Out came the superglue..patched it up then used a cut section from the outside of an old FM telescopic aerial as a ferrule to brace the latch shaft.
Refitted it and copied Checkit onto a 5.25" floppy as a test..
All good ..so did a system check with it..
..also gave me a chance to test the 287 math co pro I'd fitted.
photo attached.
I guess thats all for today.
..but at least the system is stable.

The ESS sound card has arrived ...and I have to say the ADLIB sound on Leasure suit larry is superb.
Not tried installing it on Win 3.11 yet ...nor a later game like Monkey Island ..
Then again I dont know what limitations lie in wait having never built a 286 before..

Ok ..that was a struggle but this setup is just about running Day of the Tentacle..
Had to reduce the audio buffer to half of what was recommended during setup ....just to stop it freezing up.
I'd forgotten just how long it takes to load games from floppy ...but ..part of the retro charm I guess.
Dos audio drivers must be working ok ..cos I heard the tentacles speak..🤣
Anyone got any suggestions for tweaks for this rig ?
It looks like it would benefit from a tiny bit more ram and a little bit more speed..
But I guess I cant expect miracles from a 286.
c'est la vie.

Exactly.

You can still much with a 286. I had 286 12 as well too. Works better if the video card is VGA 16 bit card, faster one better like WD90C30, this 286 can take pair of 4MB 30pin sticks, (parity or non parity if you can jumper for non-parity), little faster hard drive would help too like industrial 512MB CF on ATA to CF adapter, set the bios to type # for 500MB or 420MB or something then partition the CF on this and format. It will boot this way as long as you keep same type number for this size.

Cheers,

The CF card is restricted by the mainboards bios ..to 100mb
I cant excede this limit ..using IDE.
Even though the CF is under the control of XT-IDE ..
Exceeding 100mb is not possible due to the restrictive nature of the CHIPS bios.
Even this wasn't possible until I managed to retrofit a slightly later 1991 CW-GEAR bios.
The only way I can exceed this limit is to go SCSI.
Or ..find a more recent ..more tolerant single chip bios for the motherboard.(so far no luck there)
Hope that makes sense.
As far as ram goes ..I haven't tried going beyond 4mb in total ..since this was claimed the limit by what I found manual wise..
This 4mb was originally SIPP and was replaced with SIMM in sockets.
rgds
VS

I was talking about without XT-IDE. The type number table in the bios could go up to 504MB, take a look there in the bios settings or using a bios setting utility software that you start on the bootable dos disk.

Cheers,

I will take a look in the bios again ...but dont remember seeing anything that would help..
It is a very limited bios ..
I'll grab some images and post them up.
rgds

Hmm ..I hadn't realised the replacement GW Gear Bios had 3 pages ..
But thats it ..
Just 3 pages ..
Here they are ...hopefully you can read them ok.
Poor choice of colours I think ..and not good on photos.
rgds
VS

Well ..fwiw The drivers from Phils site for the ESS sound card were no trouble installing on DOS yesterday ...and in 3.11 tonight.
Just played canyon.mid from windoze ...and am seriously impressed by the audio quality.
GUS it aint...but for a relatively inexpensive card I have no complaints at all.
I shouldn't be left alone with time on my hands and access to fleabay .
Just splashed out on an ISA WDC WD90C30-LR VG-8000 VGA card.
It is coming from Lithuania ..so may take a while to get here ..but...what the hell.
This build will hopefully be worth it.
rgds
VS
Oh ..forgot to mention..
Nothing to do with this build...but...
There was a nasty fishy smell coming from my Amiga A1200 today ...
So spent some time recapping it..
Caught in time I'd say ..there was a lot of electrolyte splurged on the main board...thank higgs I had some IPA left.
All good.
Another job done.

Nice to see you're keeping yourself busy! I too am classed as a 'vulnerable person' so I am staying away from work for 12 weeks (2 down at least 10 more to go) - I'm also classed as a Key Worker now as I work in the IT Services department of a School and as most of the staff are now working from home dealing with support calls is taking a lot longer as we cant just ask them to pop down and see us and take a proper look at it as 1) we're socially distancing and 2) I'm working from home so not even in the same town let alone building!

I look forward to reading more on how you get on with this PC! 😀

Hi Fazza ..glad you're safe and well ...and getting some entertainment from watching this project progress.
I will be almost sorry when it is finished as I am enjoying it and learning as I go.
previous to this 386 was my oldest encounter..
286 is a whole new ball game for me.
You may have realised that the Hardware is more my forte...software ...not so much.
which is why I ask for so much help.
😁

Today I returned to the Question of the IDE Limitations imposed on this build.
I dont understand how ..but I firmly believe the motherboard bios is imposing this limit ..even though using CF cards mounted by XT-IDE
It is both frustrating and annoying ..but is something I may have to live with.
This doesn't however stop me wanting answers.
So ,,
With my Conner 100mb IDE C-H-S drive only installed..
All is good I can boot DOS6.22 no problem.

Turn off this drive in the motherboards bios and detach the drive..
Insert my XT-IDE card in the last 8 bit slot of the botherboard.
Then insert a 32 MB DOM ..fdisk format ..install DOS 6.22 ..
This boots ok..
Lets go up a size to 64 mb
Insert a 64mb CF ..fdisk ..format...install Dos 6.22 ..
Yep it boots..
Now ..we go the other side of the 100mb limit I suspect is being imposed ..
Rinse and repeat the proceedure with a 256mb CF ..
No boot
and finally a 2gb CF card ..
..and as expected ..no boot.
In all cases boot sector is found ..
In the case of the 256mb CF and the 2gb CF ...no progress after selection..
Boot is halted and the system just hangs.
This is why I suspect there is a 100mb limit on IDE hard drives being imposed by the motherboards GW Gear Bios ..
TBH I couldnt even use a 100mb hard drive with the original CHIPS bios.
Can anyone at least explain what is going on here ???
I may not be able to overcome this ..but I would at least like to understand it.
rgds
VS

...where is IanB when you need him ...?

I guess this snippet taken from a doc ... doccumenting bios limitations with respect to hard drives is relevant..
>>>>

Major BIOS Limitations:Systems with BIOS dated prior to July 1994(504 MB Limitation).Typically these BIOS will have a 504 megabyte (1,024cylinder) limitation. Prior to this date, most manufacturers' BIOS did not provide the Logical Block Address (LBA) feature needed for proper translation.

>>>>
Thing is I cannot even go above 100mb ..so my bios is seriously crippled ...and a later revision might help ...IF I could find one ...and belive me ...I have tried.

Link to the full document .
>>
http://www.homemicro.co.uk/download/pc_02_003.pdf