VOGONS


First post, by sangokushi

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I saw IBM and Dell made floppy drives with parallel port cable. Does anyone know if those drives have a proprietary cable? If there are drivers for these floppy drives to work on any laptop? Thanks.

Reply 1 of 10, by mkarcher

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As far as I know, the cables are proprietary. If your laptop has a 486 or later processor, chances are high it uses an integrated Super-I/O chip that contains both the floppy controller and the parallel port, and has a special control bit that converts the parallel port into an external FDC port. The datasheet of the super I/O chip should contain the pin assignment, so you can map parallel port pins to floppy pins if you know which Super-I/O chip is inside your laptop.

This also means that drives for different laptops that use the same Super I/O chip might be exchangable. I don't know whether the power supply for the external floppy is routed through the Super I/O or different laptops use different proprietary circuits to provide the +5V output to the drive.

Reply 2 of 10, by sangokushi

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mkarcher wrote on 2020-09-05, 19:52:

As far as I know, the cables are proprietary. If your laptop has a 486 or later processor, chances are high it uses an integrated Super-I/O chip that contains both the floppy controller and the parallel port, and has a special control bit that converts the parallel port into an external FDC port. The datasheet of the super I/O chip should contain the pin assignment, so you can map parallel port pins to floppy pins if you know which Super-I/O chip is inside your laptop.

This also means that drives for different laptops that use the same Super I/O chip might be exchangable. I don't know whether the power supply for the external floppy is routed through the Super I/O or different laptops use different proprietary circuits to provide the +5V output to the drive.

Thanks for much! My laptop's built-in floppy drive is broken. I saw those parallel port floppy drives on eBay are under $20.
The microsolutions backpack parallel floppy drive can go up to $100.

Reply 3 of 10, by mkarcher

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sangokushi wrote on 2020-09-05, 20:53:
mkarcher wrote on 2020-09-05, 19:52:

As far as I know, the cables are proprietary. If your laptop has a 486 or later processor, chances are high it uses an integrated Super-I/O chip that contains both the floppy controller and the parallel port, and has a special control bit that converts the parallel port into an external FDC port. The datasheet of the super I/O chip should contain the pin assignment, so you can map parallel port pins to floppy pins if you know which Super-I/O chip is inside your laptop.

This also means that drives for different laptops that use the same Super I/O chip might be exchangable. I don't know whether the power supply for the external floppy is routed through the Super I/O or different laptops use different proprietary circuits to provide the +5V output to the drive.

Thanks for much! My laptop's built-in floppy drive is broken. I saw those parallel port floppy drives on eBay are under $20.
The microsolutions backpack parallel floppy drive can go up to $100.

Oh, maybe I missed the point of your question. I answered your question under the assumption that you are talking about external floppy drives as a vendor option. These drives usually use the internal floppy controller. The parallel port pins get repurposed as floppy controller interface pins. This only works if the BIOS and hardware of your laptop are built to support such a drive, and you use a drive compatible to your laptop.

The backpack drives are a completely different thing: With this kind of drive, the parallel port is still used as parallel port, and the external drive contains it own floppy controller. The protocol used for communicating with the drive does not depend on the hardware, so the backpack drive will work with any laptop.

If your laptop is not built to support an external floppy drive connected to the plug for the parallel port, you can not use the controllerless external drives, and I am afraid you need something like the backpack drives.

Reply 4 of 10, by sangokushi

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Thanks again mkarcher!
Sorry I didn't give enough details in the OP.
I recently bought an old Digital (DEC) VP717 laptop for $50. It has a built-in Citizen W1D floppy drive which is broken. I google searched and this floppy drive is known to have belt issue.
This laptop does not have USB port. And I need to install some dos programs from floppy.
I tried to find a cheap floppy drive on eBay and prefer not to spend $100 for a backpack floppy drive.
That's why I asked if I can use parallel port floppy drive from other vendors.

Reply 5 of 10, by mkarcher

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sangokushi wrote on 2020-09-07, 02:44:

I recently bought an old Digital (DEC) VP717 laptop for $50. It has a built-in Citizen W1D floppy drive which is broken. I google searched and this floppy drive is known to have belt issue.

I tried to find a cheap floppy drive on eBay and prefer not to spend $100 for a backpack floppy drive.

Oh yeah, the Citizen drives again. You should be able to get a replacement belt for less than $10, and there are a lot of YouTube videos on how to change the belt. If you manage to do that yourself, that's most likely the cheapest option. As long as you follow the suggested way to change the belt (i.e. you do not disassemble the drive further than necessary), the chance of damaging or mis-adjusting the drive is very low. I have a Citizen U0DA drive with a broken belt (which I replaced already), I did not follow advices, but explored the drive way too much, and getting that drive back to proper operation is one of my long-term tasks. I understand where I went to far, and this is why I recommend you to watch videos or read how-to guides with pictures.

Reply 6 of 10, by sangokushi

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mkarcher wrote on 2020-09-07, 05:33:
sangokushi wrote on 2020-09-07, 02:44:

I recently bought an old Digital (DEC) VP717 laptop for $50. It has a built-in Citizen W1D floppy drive which is broken. I google searched and this floppy drive is known to have belt issue.

I tried to find a cheap floppy drive on eBay and prefer not to spend $100 for a backpack floppy drive.

Oh yeah, the Citizen drives again. You should be able to get a replacement belt for less than $10, and there are a lot of YouTube videos on how to change the belt. If you manage to do that yourself, that's most likely the cheapest option. As long as you follow the suggested way to change the belt (i.e. you do not disassemble the drive further than necessary), the chance of damaging or mis-adjusting the drive is very low. I have a Citizen U0DA drive with a broken belt (which I replaced already), I did not follow advices, but explored the drive way too much, and getting that drive back to proper operation is one of my long-term tasks. I understand where I went to far, and this is why I recommend you to watch videos or read how-to guides with pictures.

@mkarcher Do you know if the Citizen W1D floppy drive has standard 26 pin connectors?
The issue from my original citizen drive is not detecting any floppy disk.
I managed to find another Citizen drive from Goodwills store, though I am not sure which computer it came from.
I swapped the drive and I got an error said the floppy disk is not formatted. And formatting the disk failed.
Just wondering if both issues are related to the drive belt?

Reply 7 of 10, by liqmat

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I know those Backpack floppy drives can command a decent price, but they are invaluable if you setup a lot of early PC systems. I have two myself and will never sell them off while I'm still in this hobby.

Reply 8 of 10, by mkarcher

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sangokushi wrote on 2020-09-07, 17:09:
@mkarcher Do you know if the Citizen W1D floppy drive has standard 26 pin connectors? The issue from my original citizen drive i […]
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@mkarcher Do you know if the Citizen W1D floppy drive has standard 26 pin connectors?
The issue from my original citizen drive is not detecting any floppy disk.
I managed to find another Citizen drive from Goodwills store, though I am not sure which computer it came from.
I swapped the drive and I got an error said the floppy disk is not formatted. And formatting the disk failed.
Just wondering if both issues are related to the drive belt?

As far as I know, the Citizen W1D drive has the kind-of standard 26-pin connector in the more common flat flex cable variant. My older citizen drive has the less common 26-pin connector as 0,1 inch pin header on the drive. It is very likely that any Citizen drive you can find has a broken belt by now, unless the belt has already been replaced.

I was wrong about there being a lot of YouTube video about the Citizen W1D belt replacement. The drive in this video https://www.youtube.com/watch?v=axs3c03IKZ8 is more similar to my drive than to your drive, but I think I've seen a W1D replacement tutorial, too. The important points seem to be the same on both drives:

  • Remove the eject button to be able to push in the carriage further than possible with the button in place
  • Remove the springs that pull the carriage forward.
  • Push the carriage as far as possible to the back of the drive (might need a small amount of force
  • Lift the carriage out, be careful with the head.
  • You might need to unmount the motor that pulls the belt.
  • Do NOT unscrew the screws holding the head.
  • Do NOT unscrew the mounting screws on the motor for the spindle drive.

The W1D series of drives has a slightly different belt path and uses a belt with different dimensions compared to the U0DA shown in that video. Do NOT take advice about what belt to use from instructions for U-series drives for your W-series drive! There are a lot of forum threads about W1D belt replacement both here on VOGONS as well as on other vintage/retro computer forums, and I am sure I found the W-series belt dimensions at a lot more places than the U-series belt dimensions. If you are good enough at handling hardware to be able to swap a floppy drive in a laptop computer, you most likely can handle the belt swap procedure just fine. I encourage you to give it a go - especially as you have two of the drives (so you can lose one without bad consequences).

Reply 9 of 10, by sangokushi

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@liqmat Can you tell me what drive letter was assigned in DOS for the backpack floppy drive? I have a program only install from A drive.

@mkarcher Thanks for the instructions. I ordered a bag of belts (since I don't know the correct size) from China, it will probably take a month to arrive. I will try to replace the belt.

Reply 10 of 10, by liqmat

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sangokushi wrote on 2020-09-10, 16:58:

@liqmat Can you tell me what drive letter was assigned in DOS for the backpack floppy drive? I have a program only install from A drive.

It will take the first drive letter available. So if you disable A: and B: floppy drives in the BIOS and boot off the harddrive it would take A: I use the drives mostly for very old systems like XT and 286 class computers which sometimes only have 360K or 720K floppy drives.

The driver CD is here >> http://minuszerodegrees.net/backpack/backpack_setup_cd.htm

Here is the install floppy I imaged >>

Filename
Backpack Diskette Drive DOS & Windows Driver Disk v2.13.zip
File size
1.48 MiB
Downloads
6 downloads
File license
Fair use/fair dealing exception
Backpack Diskette Drive DOS & Windows Driver Disk v2.13.jpg
Filename
Backpack Diskette Drive DOS & Windows Driver Disk v2.13.jpg
File size
258.82 KiB
Views
64 views
File license
Fair use/fair dealing exception

Note: Sorry about the crap photo of the diskette in plastic. Forgot to scan it before getting rid of the drive. My other two drives just had the driver CD.