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skouris33
March 1st, 2014, 07:56 AM
Hi! Is there a way to add a 1.44 Mb floppy drive to an 8088 PC XT that has internal cabling for 5.25 360 Kb floppy drive? Thanks!

Chuck(G)
March 1st, 2014, 08:47 AM
Certainly. You can either modify the cable by crimping on an IDC 34 pin female header close to the existing edge connector, or get a new cable with both types of connectors--or simply use an edge-to-header adapter of the sort that used to come with 3.5"-to-5.15" drive mounting adapters. I suspect that there are still some wandering around.

Startech still offers a universal floppy cable (http://www.startech.com/Cables/Drive/IDE/32in-Universal-Floppy-Drive-Cable-Ribbon-Cable~FDAT)

SomeGuy
March 1st, 2014, 09:20 AM
Keep in mind that the 1.44mb drive will only operate with at 720k without a high density controller.

If you just need to move files back and forth to a "modern" machine, that can work well. If you are using a USB 3.5" floppy drive on the other machine, just make sure it supports 720k disks - some don't. And it is easy to use a 1.44mb disk as a 720k disk just by covering the HD notch (technically there is a difference between the two but in practice it works OK).

If you really want 1.44mb capacity, you will need an 8-bit ISA HD controller with a BIOS, but those are rather rare.

skouris33
March 1st, 2014, 09:21 AM
Thank you very much for your reply! Except for the motherboard cabling I will need a power supply adapter for 1.44 floppy too because my pc has the large one for 5.25 only. does it come with the universal floppy cable?

Stone
March 1st, 2014, 09:30 AM
Power cable adapters for the large, molex connector to the small type used on the 3.5" drive are readily available. It's also easy to make from the two parts.

SomeGuy
March 1st, 2014, 09:39 AM
Here is one example of a Molex to 3.5" floppy power adapter:

http://www.microcenter.com/product/319767/4-Pin_Molex_to_4-Pin_Floppy_Power_Adapter_Cable_-_669

They don't always refer to them as "floppy" power adapters because many other devices use this type of plug.

Stone
March 1st, 2014, 10:02 AM
Here's (http://www.ebay.com/bhp/molex-to-floppy) a bunch on eBay.

z80eu
March 2nd, 2014, 02:33 AM
It's not only about getting the correct power adapter. It's also related with having BIOS support for these high density floppy drives.
Because I ran also in these problems, I created a (hopefully good explanation) for it at http://www.z80.eu/blog/index.php (if this entry is read month later, you have to look into the blog by searching entries from March 2014).

skouris33
March 3rd, 2014, 10:15 AM
I think my system supports 1.44 Mb floppy drive because at start up I get a BIOS message referring to 1.44 Mb drive option selection. Thank you for your help!

Chuck(G)
March 3rd, 2014, 10:48 AM
You don't need a BIOS extension if you stick with DS2D floppies. At any rate, the subject has probably come up over 50 times here in the past few years.

bettablue
March 3rd, 2014, 12:25 PM
Hi! Is there a way to add a 1.44 Mb floppy drive to an 8088 PC XT that has internal cabling for 5.25 360 Kb floppy drive? Thanks!

I use a MicroSolutions Backpack drive I bought from a member here in the forums. It connects via parallel port, and allows my to keep both of my full height 5.25" floppy drives installed in the main PC, and I didn't have to lose a bay needed for another drive, like a full height hard disc, that most XT's came out with. I know a lot of XT owners, who have replaced their full height floppy and hard disc drives, with half height ones, but as user, Someguy, and others have reiterated, they don't have a full 1.44 MB 3.5" drive without getting a higher density controller. My installation however; with my Backpack drive connected via parallel port, I didn't have to use an internal drive bay, and kept all 4 of my PC's full height bays; two full height hard discs in the IBM 5161 expansion unit plus the two full height floppy drives in the main PC.

Here's a link to a brand new one on E-Bay that is selling for $39.95. But in all reality, you could possibly find one for far less. Mine, for instance, was a used drive, and I paid only $10.00 including a 5.25, and 3.5" install floppy. The new ones don't come with 5.25" install floppy discs though. I can send you an install floppy if you decide to go this rout. BTW, MicroSolutions also makes/made CD-ROM Backpack drives, CD-reader/re-writable drives, but anything writable will not work with the older PC/XT, and clones. They even have a tape drive that works with the older PC/XT's and compatibles.

The floppy and CD-ROM drives work great with my 5150 system. Although you can typically only have one or the other installed at any given time. I have my system set up so that the drives don't automatically load at startup, and will only run when I run the command for which drive I prefer. It did take some playing, but I got it to work with both floppy, and CD-ROM. Personally, I love mine. It just gave me so much more freedom to move files, and programs to and from my IBM 5150 PC. Of course, using the CD-ROM to bring stuff to the 5150 systems hard discs was so much easier as well. Its really amazing how just adding a single drive made in the usability of the entire system.

Anyway, here are a couple of links to both a new MicroSolutions Backpack floppy, drive, and a used one. There doesn't seem to be nearly as many on E-Bay as there were only a few weeks ago. Perhaps, if you're willing to go with the backpack option, someone here might be able to sell you one.

New:
http://www.ebay.com/itm/MicroSolutions-Backpack-1-4MB-Parallel-Floppy-Drive-NEW-/271098680792?pt=US_Floppy_Zip_Jaz_Drives&hash=item3f1ebd95d8

Used: (I don't like this one because its missing the faceplate.
http://www.ebay.com/itm/MicroSolutions-014350-00722-External-Floppy-Disk-Drive-/151226154069?pt=US_Floppy_Zip_Jaz_Drives&hash=item2335c7fc55

k2x4b524[
March 3rd, 2014, 03:23 PM
wasn't there a version of DR-Dos that supported high density without the need for a controller, out of the box? Just chuck the 1.44 in an it worked? Hell, wasn't there a thread about this?-

SpidersWeb
March 3rd, 2014, 05:26 PM
Well to be clear, there is two issues:

- older floppy controllers do not support the 500kbps data rate used on 1.2 or 1.44 media
- BIOS can't tell DOS the real drive spec

Software can fix the second point, but you're always going to need a controller capable of the higher data rate (If needed, I just grab a cheap 16 bit multi IO card and disable the features I don't want).

Sounds like the OP actually has 1.44 support in the BIOS? Which should make things pretty smooth sailing if correct.

Caluser2000
March 3rd, 2014, 05:39 PM
Plasma made a post bout DrDos http://www.vintage-computer.com/vcforum/showthread.php?37867-Adding-1-44-MB-Drive-to-5150-Clone-as-B-%28PC-Retro%29-Problem/page27

And Mike Chambers http://www.vintage-computer.com/vcforum/showthread.php?22905-MS-DOS-3-3-bootsector-patching-for-1-44-MB-drive-on-XT&p=160985#post160985

You need to use a 16 bit controller though but if the bios already shows 1.44meg fdd it may be just a matter of using a later dos.

SomeGuy
March 3rd, 2014, 06:49 PM
I think my system supports 1.44 Mb floppy drive because at start up I get a BIOS message referring to 1.44 Mb drive option selection. Thank you for your help!

I'm curious as to exactly what type of machine or motherboard this is. Does this use an integrated disk controller on the motherboard? If so, the manufacturer very well could have included bios HD support.

Chuck(G)
March 3rd, 2014, 08:24 PM
Peek inside of your PC XT and take a look at the floppy controller. It sounds as if you've got an aftermarket addition. It's also possible that you have the PC/286, which really isn't a PC XT at all--just looks like one.

skouris33
March 4th, 2014, 06:36 AM
I think that my PC has an aftermarket addition, but I'm certain that it is an 8088 because I have run many DOS diagnostics programs that certified this, along with its speed (which is 4.77 MHz without the turbo mode)

skouris33
March 4th, 2014, 08:06 AM
Yesterday I ordered the motherboard universal cable along with power molex adaptor. In about 3 weeks, when they arrive, I will let you know if it worked!

konc
March 5th, 2014, 08:15 AM
I use a MicroSolutions Backpack drive
...

Thank you so much for informing us about this! I wanted a similar solution and after reading your post searched for it on ebay. A new & sealed one is on its way from a kind seller willing to ship it over to Greece for the excellent price of £13.00 in total!

bettablue
March 5th, 2014, 08:35 AM
Thank you so much for informing us about this! I wanted a similar solution and after reading your post searched for it on ebay. A new & sealed one is on its way from a kind seller willing to ship it over to Greece for the excellent price of £13.00 in total!

Glad to be of some help. Personally, since I use the backpack drive and a 1.44 external USB floppy on my Windows 7 computer, I almost don't need a tweener. It takes a bit of time to move things via floppy, but it works for me.

skouris33
March 22nd, 2014, 08:28 AM
Yesterday my universal cable for floppy disks arrived and I connected it. It worked fine! Now I have 2 floppy disks in my 8088, one 360 Kb and one 1.44 Mb! :)

Stone
March 22nd, 2014, 08:29 AM
Bravo, filè moy! :-)

bettablue
March 22nd, 2014, 02:37 PM
Where does one get the adapter to install the 3.5" disc drive into the 5.25" drive bay? I realize I may not be able to get the full 1.44 MB, but if I can get it to read 800Kb, that could still be useful. I would just need to learn to make 800Kb discs on my tweener, or Windows 7 computer.

luvit
March 22nd, 2014, 02:42 PM
reachout to Stone or go to here: amzn.com/B009MGGWQE (amzn.com/B009MGGWQE)
you'll be making 720K diskettes.

Caluser2000
March 22nd, 2014, 03:05 PM
Where does one get the adapter to install the 3.5" disc drive into the 5.25" drive bay? I realize I may not be able to get the full 1.44 MB, but if I can get it to read 800Kb, that could still be useful. I would just need to learn to make 800Kb discs on my tweener, or Windows 7 computer.As luvit stated you'll get 720k formated disks in Dos Thomas.

Stone
March 22nd, 2014, 03:22 PM
reachout to Stone ....Yup, I've got one if you want it. :-)

bettablue
March 22nd, 2014, 06:00 PM
Yup, I've got one if you want it. :-)

No problem! I saved the link so when I'm ready to buy, I'll get one through Amazon.com, or E-Bay. Right now though, I have too many eggs in my basket, and need a way to get everything I still want/need, like that power supply fan, the wedge mouse, and a few other minor odds and ends. I have to raise some money first though. If I can sell my Mac SE, I'll definitely have the money I need for other things.

Caluser2000
March 22nd, 2014, 06:24 PM
Yesterday my universal cable for floppy disks arrived and I connected it. It worked fine! Now I have 2 floppy disks in my 8088, one 360 Kb and one 1.44 Mb! :)Excellent. Well done. Any chance of a pic or two of this beast at all?

Stone
March 22nd, 2014, 06:38 PM
No problem! I saved the link so when I'm ready to buy, I'll get one through Amazon.com, or E-Bay.Just be sure that when you get one that it comes with the necessary adapters, i.e., power and cardedge, if you need them to connect to your existing hardware setup.

skouris33
March 23rd, 2014, 06:53 AM
Hi! I tried to upload a picture of my system in zip form but the file is to large to upload, is there another way to do it?

Stone
March 23rd, 2014, 07:13 AM
Put it on DropBox or some other file host.

skouris33
March 23rd, 2014, 07:15 AM
Ok I'll try it, thanks!

skouris33
March 23rd, 2014, 07:29 AM
This is the link with my system picture!

https://www.dropbox.com/s/gbohj2swjkkf0yv/DSC00676.JPG

luvit
March 23rd, 2014, 07:38 AM
that's a sweet looking setup you got there.
i love that nice clean look of it being taken care of properly.

skouris33
March 23rd, 2014, 07:42 AM
Thank you! :)

sparky4
April 1st, 2014, 09:54 PM
i am having the same issue here my XT and XT clone only support DSDD disk formats and not DSHD I have a 8 bit isa hard drive controller card form wester digital and a eprom porogrammer and my XT and clode do not know what a 27256 chip is so they do not boot when i use the more up todate bios.... Is there a awesome bios for this machine at 8kb? sigh

sparky4
April 1st, 2014, 10:01 PM
I have an eeprom programmer and a ibm xt clone and actual ibm XT and the machines do not know what is a 27256 chip ... so i am thinking of alternatives


Can i use a network card to add a floppy bios extention chip on it? or use one of my 8 bit isa hard drive controller cards as a pseudo floppy controller card? what can i do?

sergey
April 2nd, 2014, 01:29 PM
I have an eeprom programmer and a ibm xt clone and actual ibm XT and the machines do not know what is a 27256 chip ... so i am thinking of alternatives

Can i use a network card to add a floppy bios extention chip on it?

Yes, you can put a BIOS extension ROM in a network card. The network card hardware doesn't really care what code is inside the BIOS extension ROM :-)
Another question is where do you want to get the floppy BIOS extension ROM code? And why? It is completely possible to boot from 720 KB 3.5" floppies with the original XT BIOS, and load 2M utility after that to support 1.44 MB diskettes. So unless you really have a need to boot from 1.44 MB diskettes I wouldn't bother with the BIOS support.


or use one of my 8 bit isa hard drive controller cards as a pseudo floppy controller card? what can i do?

Sorry, lost you here... what is pseudo floppy controller? :-)

modem7
April 2nd, 2014, 10:51 PM
I have an eeprom programmer and a ibm xt clone and actual ibm XT and the machines do not know what is a 27256 chip
The IBM XT (IBM 5160) does 'know' about 27256 EPROMs. See [here (http://www.minuszerodegrees.net/bios/bios.htm)].


It is completely possible to boot from 720 KB 3.5" floppies with the original XT BIOS ...
Per the procedure [here (http://www.minuszerodegrees.net/5150_5160/720k/5150_5160_boot_using_720k.htm)].


... and load 2M utility after that to support 1.44 MB diskettes.
With the requirement for a floppy controller that supports HD, per the procedure [here (http://www.minuszerodegrees.net/transfer/35_inch/2m-xbios.htm)].

lowen
April 4th, 2014, 05:14 AM
Seeing this thread, I remembered a couple of dtk controllers I have had in a box in my basement for at least 15 years, and they were somewhat old when I got them. So, last night I dug them out, and here's a couple of pics:

1811618117

The model# is 'PII-151B' and it is called a 'Mini/Micro-2 FDC Card' and it supports two drives with jumper selectable capacities (hopefully that second pic is readable).

I need to set up my Advin Pilot U44+ EPROM burner anyway, and test reading the 2764s on these boards might be a good candidate.

I also found a Conner 2Mb floppy controller, but it's designed to run a floppy tape drive (got a couple of those, too). I seem to remember the two dtk controllers being connected to tape drives when I got them; a standard HD floppy controller was the minimum controller allowed for floppy tape (IIRC) even on an XT.

modem7
April 4th, 2014, 02:09 PM
I need to set up my Advin Pilot U44+ EPROM burner anyway, and test reading the 2764s on these boards might be a good candidate.
I could then add the resulting images to the collection at http://www.minuszerodegrees.net/rom/rom.htm

bettablue
April 4th, 2014, 06:10 PM
Hey Spidey!

"If needed, I just grab a cheap 16 bit multi IO card and disable the features I don't want" (If you wish, you can reply privately) How does that relate to adding full 1.44 Mb capacity on 3.5" discs? Or am I getting something confused, which I seem to do a lot. I have a 5150 computer coming in that I intend to restore to its original configuration with the exception of having a XT-CF Lite installed, but since the computer only has one floppy drive, I have been also considering the addition of a 3.5" 1.44 MB floppy drive.

I've seen mention of high density controllers, taping over the HD hole to enable 720Kb mode on another floppy drive, but your idea sounds better, if it will work on a 5150.


Well to be clear, there is two issues:

- older floppy controllers do not support the 500kbps data rate used on 1.2 or 1.44 media
- BIOS can't tell DOS the real drive spec

Software can fix the second point, but you're always going to need a controller capable of the higher data rate (If needed, I just grab a cheap 16 bit multi IO card and disable the features I don't want).

Sounds like the OP actually has 1.44 support in the BIOS? Which should make things pretty smooth sailing if correct.

Caluser2000
April 4th, 2014, 06:29 PM
It's been mentioned a zillion times on vcf. Also DRDos 7 doesn't seem to require any extra drivers and is able to boot right off a 1.44 meg boot floppy.

sparky4
May 14th, 2014, 05:33 AM
ok ^^ it has been a while but i will try it out later ^^