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Software-only XT/IDE Controller

pearce_jj

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As an experiment, I've configured a BIOS that I think might make a compact flash card attached to a standard 16-bit IDE controller work in an XT class machine (i.e. an 8-bit ISA slot).

The BIOS image is 8K. To make this work, you'll need a 16-bit IDE controller card, somewhere to put the BIOS such as a EPROM on a NIC or a universal ROM board, and be able to disable the ROM BIOS on the IDE controller either through jumpers or by pulling the chip. The IDE controller must be using ports 1F0h and 3F0h.

Anyone interested in trying this?
 
I'm game, i have a spare CF Card and adapter on order, should arrive tomorrow, Is there a limit to the size of CF card ?

Malc
 
Slightly depressingly, the BIOS seems to work. More info here - so another storage option for XT class machines.
 
so you could theoretically buy a fairly cheap, 16 bit multi-IO card (I've seen them on ebay for about 8 dollars), replace the BIOS with yours, attach a CF device, and not only get cheap big storage, but also high density floppy support too, not to mention serial+LPT ports.
Well, the BIOS would then need to have 1.2 and 1.44mb floppy support put in it, but don't we have that available somewhere?

that's crazy simple. I love it.
yes, kind of depressing in that we went to all that work with our own designs and this was right under our noses the whole time!
 
Yes I think so. It needs a CF to IDE adapter, FDD type molex power adapter, ROM chip and programmer or a universal flash BIOS board - so it's not going to be an $8 solution for everyone.

Also this is limited to 8-bit port IO - the slowest option for 8088 machines - but that's not the point; it seems to work.

This is also why I was wondering about the SB-Pro cards; if we can bring 'up' the IDE interface ports with some BIOS code....
 
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I think I posted something about this awhile back--the issue was where to put the BIOS ROM for me. Most 16-bit IDE/floppy controllers don't have BIOS ROMs.
 
I have a Prime 2 16-bit IDE I/O card in an 8-bit slot in my IBM XT :)
4 Gb Compact flash card and adapter with Dos 6.22 installed
Rom board flashed with the modded bios and FDC.BIN which i downloaded from the N8VEM website
1.44 Mb 3.5" floppy drive
2 serial ports ( working )
1 printer port ( working )
1 Game port ( Untested )

The initial OS install was slow ( took nigh on 50 mins ) I used Dos 6.22 as it was closest to hand but once installed it all seem's to work fine apart from MSD doesn't want to play nicely.

I have tried a couple of other 16-bit cards and they also worked, all in all a good job and definitely another option :cool:
 
I have a Prime 2 and have had zero luck getting a CF card to work with the modded BIOS using 3 different CF cards.

Did you change the card?

I have HD set to Primary with no int selected. The floppy enabled and working with a 3.5" as a 720k.

What FDC.BIN file at N8VEM?
 
Default jumper settings are working for me as per here

FDC-BIOS.BIN is here



I have a Prime 2 and have had zero luck getting a CF card to work with the modded BIOS using 3 different CF cards.

Did you change the card?

I have HD set to Primary with no int selected. The floppy enabled and working with a 3.5" as a 720k.

What FDC.BIN file at N8VEM?
 
Default jumper settings are working for me as per here

FDC-BIOS.BIN is here

I have an IDE / Floppy only card which is also labeled Prime 2 and it no work. :(

Andrew states somewhere on N8VEM that that .BIN file is a dump from an XT floppy controller that he couldn't get to work with the XTIDE BIOS. Of course that was 3 years ago. That BIOS is working with the floppy controller on the Prime 2 card?
 
Yes it worked for me, on boot up it see's the floppy as a 1.44 Mb which it is.

Another card i tried and works is a Diamond Flower MIO-400 KF REV F and also my silicon valley ADP 60/70

I also have a 8-bit HD floppy controller in another machine, i dumped the bios today and tried that with the modded BIOS and that works too, I have attached the BIOS from my HD 8-bit floppy controller.
 

Attachments

  • DTK-FDC-BIOS.zip
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Check the port addresses, they need to be those two ranges. CF cards often don't like to be slave so check also CF card adapter is set to master, card needs power of course. Is the XTIDE BIOS appearing and showing no devices detected?
 
Not listed on stason.

Card only lists jumpers as HD PRI/SEC HD ENA/DIS, etc. No actual port numbers are listed. CF card comes up on another system using the same CF adapter and all settings (master) verified. Still no love.
 
Set Pri/Ena, but also on the link posted above for the Prime 2 card there is a jumper "IDE(AT) drives supported" which needs to be set too (Malc, can you confirm my assumption of that?).
 
Set Pri/Ena, but also on the link posted above for the Prime 2 card there is a jumper "IDE(AT) drives supported" which needs to be set too (Malc, can you confirm my assumption of that?).

This has all been done.

This is not his card and only has jumpers for setting PRI/SEC, ENA/DIS and IRQ no other jumpers for the HDD controller. The only other jumper is for enabling and disabling the floppy controller on the card which would be the only jumper I have not moved at this point.
 
Yes I think so. It needs a CF to IDE adapter, FDD type molex power adapter, ROM chip and programmer or a universal flash BIOS board - so it's not going to be an $8 solution for everyone.
Sorry for asking something probably obvious to others but not to me. Some people here mentioned replacing ROM located in IDE controller. Some mention universal ROM board and some replacing motherboard BIOS. These are basically if I get it right two different things. One is completely new BIOS and the other one is just an add-on BIOS. I have a Commodore PC10-III with non standard self-configuring BIOS. I have a programmer and an EPROM. What is the right approach for me ?
 
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