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asiawatcher
May 2nd, 2010, 12:47 PM
WILL AN 8088 WORK WITH HIGH DENSITY DRIVES ?

also can an 8088 work with THIS controller

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=350347523121&ssPageName=STRK:MEWAX:IT

and a modern IDE 20gb or more hard drive ?

cheers !

per
May 2nd, 2010, 01:07 PM
It does support HD disks if the following conditions are true:

A disk drive controller that does HD drives is used (like the ones found on various IDE/Floppy 16-bit multicards. Since the floppy-interface only uses the lower 8 bits, those 16-bit multicards can be used in a 8-bit bus for just that purpose.)
An Int13h handler that knows how to handle a disk controller in HD mode is installed (either as a BIOS-expansion or a driver. It may also already be present within the main BIOS in some rare cases.)
An OS supporting HD drives is being used.


About the IDE-like card, it may actually not be IDE at all. It can for instance be a Mitsumi interface or some other nonstandard CD-ROM interface. You'll have to do some research for yourself there to know for sure. I really doubt it is IDE because it lacks a ROM-chip, and therefore the BIOS won't support it by default.

modem7
May 2nd, 2010, 01:34 PM
The FCC ID of the card indicates part/model number GCD-R420B.
An Internet search using "GCD-R420B" suggests that the card is used with a GCD-R420B CD-ROM drive.

Chuck(G)
May 2nd, 2010, 01:45 PM
The only way this controller would work with a high-density floppy drive is if the drive was an LS-120--and good luck with the drivers on that one.

asiawatcher
May 2nd, 2010, 02:02 PM
thank you all for your answers another question those 16-bit conteroller cards either for floppies or hard drives will they work with my 8-bit only isa slots ? my vga card is 16-bit isa but works fine on my 8-bit isa port

also what im looking is where to find high density floppy controllers for my 8088 and a hard disk IDE controller to plug it to a more modern time ide hard drive (my old hdd is busted and it uses 2 ribbon cables and 1power plug)

so if i buy this controller card for cdrom like i quoted above from ebay which you guys say isnt a hard disk controller or even floppy controller will i be able to install a dvd/cdrom on my 8088 ?

cheers

asiawatcher
May 2nd, 2010, 02:06 PM
to make you guys understand what im trying to do is i got an 8088 that its double sensity floppies arent working well or at all and my old hard drive is busted i want to make this work again

my huyndai super 16v is a 8088 with 640k ram onboard floppy controller and a seperate very large ide controller that has 2 ribbon cables going to the drive

now i was wondering if i can make this work again even with newer technology parts like high density drives and newer style hard drives all i want to do is make it work again

and of cours eif i can add cd rom or high density drives it will be even better !

cheers

per
May 2nd, 2010, 02:26 PM
to make you guys understand what im trying to do is i got an 8088 that its double sensity floppies arent working well or at all and my old hard drive is busted i want to make this work again

my huyndai super 16v is a 8088 with 640k ram onboard floppy controller and a seperate very large ide controller that has 2 ribbon cables going to the drive

now i was wondering if i can make this work again even with newer technology parts like high density drives and newer style hard drives all i want to do is make it work again

and of cours eif i can add cd rom or high density drives it will be even better !

cheers

Adding a HD floppy drive in such a system is best if you got a floppy drive adapter with a BIOS-extension on it. They might be hard to come by, but they exist. Anyways, you can allways just use a HD controller without a BIOS extension (like those 16-bit multicards), and use 720KB formatted HD disks (that's what I does). You will be able to use all 720KB if you have a recent version of DOS, like 3.3 or 5.0, even if many programs will register the disk as only 360KB (because of that, the disks have to be formated in a more recent computer).

As for IDE drives, you'll need a 16->8 bit adapter. We had a project here on therse forums not long ago where we designed one, however, you will need to get the parts and build it yourself. As for comercial 16->8 bit IDE adapters, they exist, but every single one I have seen for sale is way overpriced, and they doesn't properly support anything greater than ~500MB anyways.

asiawatcher
May 2nd, 2010, 03:00 PM
thats great where are the plans for that adapter ?

Raven
May 2nd, 2010, 03:00 PM
A disk drive controller that does HD drives is used (like the ones found on various IDE/Floppy 16-bit multicards. Since the floppy-interface only uses the lower 8 bits, those 16-bit multicards can be used in a 8-bit bus for just that purpose.)


Are you certain that this applies to all 16-bit multicards? I haven't tried it, and have no reason to doubt, but that seems like a very sweeping generalization and before shelving that knowledge I want to verify that that's a truly universal thing.


thats great where are the plans for that adapter ?

There has been a production run and lots of us have boards from that run (including me). There was recently talk of another production run, but I don't know if there was enough interest for it to end up going through at that time. It's called the "XT-IDE" and it's based on the N8VEM board (iirc).

Chuck(G)
May 2nd, 2010, 03:43 PM
Permit an incredibly stupid question on my part--it's Sunday and I'm feeling thickheaded.

Why do you feel the need to replace the floppy (or hard drive) controller in your system? They rarely fail on their own. Why not just replace the floppy drive with a 3.5" unit? The system specs say that it supports 3.5" drives. You can use a 3.5" high-density drive--almost all can accept DS2D media for 720K--and you can create your own DS2D media from DSHD by taping over the media type aperture in the drive jacket.

It sounds to me as if you're making things too complicated.

vwestlife
May 2nd, 2010, 04:59 PM
WILL AN 8088 WORK WITH HIGH DENSITY DRIVES ?

also can an 8088 work with THIS controller

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=350347523121&ssPageName=STRK:MEWAX:IT

and a modern IDE 20gb or more hard drive ?

cheers !

As modem7 mentioned, that is a controller for a proprietary (and long-obsolete) CD-ROM interface. Although it has a 40-pin connector, it is not an "IDE" controller as the seller claims, and it also doesn't have an onboard ROM, so even if it was an "IDE" controller (which it's not), you wouldn't be able to boot from it on an XT-class system.

As for floppy drives... high-density 5.25" 1.2MB and 3.5" 1.44MB floppy drives will work just fine in an XT-class system, as long as you have a controller specifically designed for this purpose, with an onboard ROM. Standard AT-type floppy controllers will not work since they don't have the onboard ROM, and standard XT-type controllers will only support low-density 360K and 720K floppies.

And as others have also mentioned, you can plug a 3.5" floppy drive into a standard XT-type floppy controller and it will work just fine with "double-density" 720K floppy disks. I just retrofitted three different XT-class systems (an original IBM PC, a Packard Bell Turbo XT clone, and a Tandy 1000) with 3.5" floppy drives, and all can read and write to 720K floppy disks just fine without needing to change or upgrade the floppy controller. The only thing you may run intro trouble with is formatting 720K disks, but the easiest solution to that is to simply format the disks on another computer.

asiawatcher
May 2nd, 2010, 06:14 PM
Are you certain that this applies to all 16-bit multicards? I haven't tried it, and have no reason to doubt, but that seems like a very sweeping generalization and before shelving that knowledge I want to verify that that's a truly universal thing.



There has been a production run and lots of us have boards from that run (including me). There was recently talk of another production run, but I don't know if there was enough interest for it to end up going through at that time. It's called the "XT-IDE" and it's based on the N8VEM board (iirc).


where can i buy one such kit? will you sell me yours or who sells them !!!

Raven
May 2nd, 2010, 07:40 PM
where can i buy one such kit? will you sell me yours or who sells them !!!

I am not selling mine, and none are for sale officially at the moment - they might be again soon though.

andy
May 2nd, 2010, 08:19 PM
Back when 8088 systems were old, but not completely obsolete, I can remember adding a HD floppy controller card to an XT. It replaced the standard floppy controller, and had a BIOS extension to add support for 1.44, and 1.2MB drives (it also supported 360k and 720k drives). You had to tell it what type of drives were attached using jumpers, but once the card was installed it was completely transparent. No special drivers were needed (other than using a version of DOS that supported HD drives). Unfortunately, the board and XT are both long gone, and I don't remember who made it. It wasn't expensive, or hard to find in the early 90's.

Chuck(G)
May 2nd, 2010, 08:49 PM
There were several. Sysgen Omnibridge and Microsolutions Compaticard were two of the more popular ones (if you get the MS, get the CC IV, not the I or II). Jameco and JDR both offered similar cards. DTK had the MiniMicro. There were many others, such as the Western Digital WD-1002A-FOX.

modem7
May 2nd, 2010, 11:08 PM
to make you guys understand what im trying to do is i got an 8088 that its double sensity floppies arent working well or at all and my old hard drive is busted i want to make this work again
A very common problem with 5.25 inch floppy drives that have been sitting idle for many years, is that the lubrication on the slide rails hardens. Have you tried re-lubricating the rails?


Adding a HD floppy drive in such a system is best if you got a floppy drive adapter with a BIOS-extension on it. They might be hard to come by, but they exist.

As for floppy drives... high-density 5.25" 1.2MB and 3.5" 1.44MB floppy drives will work just fine in an XT-class system, as long as you have a controller specifically designed for this purpose, with an onboard ROM.
An example is shown at http://www.a1usedcomputers.com.au/shop/prodView.asp?idproduct=315
That particular card supports two drives on one connector (A: + B:) and two drives on the other connector. The jumpers on the right side are used to inform the card as to the type of drives attached (360K/1.2M/720K/1.44M). The first two jumpers are for the first drive, the next two jumpers for the next drive, and so on.

asiawatcher
May 3rd, 2010, 01:52 AM
will this controller do what xt-ide does ?

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=350055349829&ssPageName=STRK:MEWAX:IT

cheers

modem7
May 3rd, 2010, 02:58 AM
will this controller do what xt-ide does ?
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=350055349829&ssPageName=STRK:MEWAX:IT
In the beginning ...
* For PCs and XTs, you bought an 8-bit IDE drive and matching 8-bit IDE controller. In this post, I'll call that 8-bit IDE.
* For ATs, you bought a 16-bit IDE drive and matching 16-bit IDE controller. In this post, I'll call that 16-bit IDE.

The controller you've pointed to is an 8-bit controller probably designed for 8-bit IDE drives. If so, you would need to find an 8-bit IDE drive. The Miniscribe 8450XT drive advertised by the same seller is an 8-bit IDE drive according to Google Books (described as "XT IDE"). If those two items do indeed match, that's going to be a very expensive solution.

Note that 8-bit IDE drives and controllers are uncommon (and accordingly expensive). That's where the XT-IDE controller created by members of these Forums comes into play. It's an 8-bit controller designed to connect to a 'standard' 16-bit IDE drive.

asiawatcher
May 3rd, 2010, 03:20 AM
right i see thanks

and i guess this wont do the trick also right or it will ? http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170478230965

some isa cards work on both 16-bit and 8-bit isa ports my 8088 vga card is 16-bit isa plugged in 8-bit port but still works

if this wont work also and except from this forum (your project) where can i find such an ide controller elsewhere anywhere ? any price !!!

let me know cheers :(

per
May 3rd, 2010, 03:21 AM
As for floppy drives... high-density 5.25" 1.2MB and 3.5" 1.44MB floppy drives will work just fine in an XT-class system, as long as you have a controller specifically designed for this purpose, with an onboard ROM. Standard AT-type floppy controllers will not work since they don't have the onboard ROM, and standard XT-type controllers will only support low-density 360K and 720K floppies.

And as others have also mentioned, you can plug a 3.5" floppy drive into a standard XT-type floppy controller and it will work just fine with "double-density" 720K floppy disks. I just retrofitted three different XT-class systems (an original IBM PC, a Packard Bell Turbo XT clone, and a Tandy 1000) with 3.5" floppy drives, and all can read and write to 720K floppy disks just fine without needing to change or upgrade the floppy controller. The only thing you may run intro trouble with is formatting 720K disks, but the easiest solution to that is to simply format the disks on another computer.

That is if you are using a 3.5" drive that only supports Double Density (720KB).

Here is what I have experience by actual trial-and-failing:

Early-BIOS XT + DD floppy controller + DD floppy drive -> Works with DD disks, but not nessecarely DD disks written to by a HD drive. Some programs detects the disk format wrong for 720KB disks unless a driver is installed (DOS is not one of them).
Early-BIOS XT + DD floppy controller + HD floppy drive -> Doesn't work at all.
Early-BIOS XT + HD floppy controller + DD floppy drive -> Works with DD disks, but not nessecarely DD disks written to by a HD drive. Some programs detects the disk format wrong for 720KB disks unless a driver is installed (DOS is not one of them).
Early-BIOS XT + HD floppy controller + HD floppy drive -> Works with all DD-formated disks, but some programs detects the disk format wrong for 720KB disks unless a driver is installed (DOS is not one of them).


None of the floppy-controllers I used had BIOS-Extension ROM's installed, and the BIOS disk routine were the only one used. This proves that most AT HD floppy controllers are backwards-compatible, and don't need a BIOS-extension for DD operation in an old PC/XT.

About the 16-bit multicard question, most of them should work. The only reason those cards are 16-bit is because the IDE port on them uses all of the 16 bits, but the floppy adapter uses only the lower 8 bits. I don't really think anybody made a 16-bit floppy controller chip at all, I haven't seen one yet at least (and I have seen quite a lot of ISA cards).

modem7
May 3rd, 2010, 03:45 AM
NOTE: The use of "ISA" below is done in a generic sense.


some isa cards work on both 16-bit and 8-bit isa ports my 8088 vga card is 16-bit isa plugged in 8-bit port but still works
That's because the designer specifically designed the card that way.

There could be a 16-bit IDE controller out there that senses that it's in an 8-bit slot and when it does, switches from 16-bit to 8-bit mode ISA communication. Anybody know one?


and i guess this wont do the trick also right or it will ?
You would either need somebody to tell you that that particular controller will do 8-bit ISA operation, or you would need to find some technical information on the controller. Buying the card then trying 8-bit ISA operation would 'brave'.

per
May 3rd, 2010, 04:12 AM
You would either need somebody to tell you that that particular controller will do 8-bit ISA operation, or you would need to find some technical information on the controller. Buying the card then trying 8-bit ISA operation would 'brave'.

If it's a one-chip controller (like most of them), you can just look it up the datasheet for the chip to check how many bits it has inputs for. Generic one-chip floppy disk controllers are only 8-bit in all of the cases I have seen so far.

The chip on the card I use in my XT is a GM82C765B, and it's present on a 16-bit multicard. The datasheet for the chip state that it has 8 data inputs, and there is not a word about 16-bit operation.

Chuck(G)
May 3rd, 2010, 09:42 AM
That GM82C765B is just a clone of the WD37C65; probably the first single-chip PC floppy controller. I know of no 16-bit legacy floppy controllers (this lets out gizmos like Catweasels). As a matter of fact, the standard primary controller I/O ports, DMA and interrupt has been prety much fixed since the days of the 5150. Most modern southbridge chips implement ISA DMA for only that single device. Sort of like carrying the horse in the front seat of your new SUV.

mikey99
May 3rd, 2010, 10:27 AM
JDR Microdevices had a card that would support HD drives on an 8088 (see picture below).

Also, I noticed this on ebay, the picture is different and the price is too high :-)
But it has a Make Offer option , try a lowball offer and see what happens.

http://cgi.ebay.com/Modular-Circuit-Technology-MCT-FDC-HD-FDC-Card-Used-/300193335503?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item45e4eac8cf