Doesn't the drive have an external power connector?

Does the drive not respond when attached and you try to do a

DIR B:

in dos ?

dominusprog wrote on 2024-05-19, 15:50:

Doesn't the drive have an external power connector?

I could not see any power socket, which is indeed suprising because I am not sure if a parallel port can deliver enough power for a disk drive.

Can you post some more pictures of the floppy drive? There might be some kind of non-standard power plug on it.

weedeewee wrote on 2024-05-19, 16:28:

Does the drive not respond when attached and you try to do a

DIR B:

in dos ?

I tried and no it does not work.

mtest001 wrote on 2024-05-19, 19:24:

weedeewee wrote on 2024-05-19, 16:28:

Does the drive not respond when attached and you try to do a

DIR B:

in dos ?

I tried and no it does not work.

Dangit, I was hoping it would work out of the box since I'm fairly certain on later model compaq m700 it actually does work, though I would have to check to be 100% certain.
I guess a driver of some sort will be required for these older machines, although since the bios sees the external drive when attached... mmmh I do not know.

weedeewee wrote on 2024-05-19, 20:26:

mtest001 wrote on 2024-05-19, 19:24:

weedeewee wrote on 2024-05-19, 16:28:

Does the drive not respond when attached and you try to do a

DIR B:

in dos ?

I tried and no it does not work.

Dangit, I was hoping it would work out of the box since I'm fairly certain on later model compaq m700 it actually does work, though I would have to check to be 100% certain.
I guess a driver of some sort will be required for these older machines, although since the bios sees the external drive when attached... mmmh I do not know.

Note that when this is connected, that is no longer a parallel port at all, and the pinouts change. It's worth checking the cable itself for damage inside the connectors; it may be missing something that tells the computer to change the pinout and put 12V or 5V on some pin to power it.
It effectively turns the LPT port into "just a bunch of pins".

AngelaTheSephira wrote on 2024-05-19, 21:01:

weedeewee wrote on 2024-05-19, 20:26:

mtest001 wrote on 2024-05-19, 19:24:

I tried and no it does not work.

Dangit, I was hoping it would work out of the box since I'm fairly certain on later model compaq m700 it actually does work, though I would have to check to be 100% certain.
I guess a driver of some sort will be required for these older machines, although since the bios sees the external drive when attached... mmmh I do not know.

Note that when this is connected, that is no longer a parallel port at all, and the pinouts change. It's worth checking the cable itself for damage inside the connectors; it may be missing something that tells the computer to change the pinout and put 12V or 5V on some pin to power it.
It effectively turns the LPT port into "just a bunch of pins".

There was mention of this

mtest001 wrote on 2024-05-19, 12:36:

I did connect it to the laptop, then in the BIOS there is an option to indicate that an external FDD is present but it does not seem to have any effect.

So the bios detects it.
but, indeed that does not rule out that some wires might be faulty.

weedeewee wrote on 2024-05-19, 21:13:

There was mention of this […]
Show full quote

AngelaTheSephira wrote on 2024-05-19, 21:01:

weedeewee wrote on 2024-05-19, 20:26:

Dangit, I was hoping it would work out of the box since I'm fairly certain on later model compaq m700 it actually does work, though I would have to check to be 100% certain.
I guess a driver of some sort will be required for these older machines, although since the bios sees the external drive when attached... mmmh I do not know.

Note that when this is connected, that is no longer a parallel port at all, and the pinouts change. It's worth checking the cable itself for damage inside the connectors; it may be missing something that tells the computer to change the pinout and put 12V or 5V on some pin to power it.
It effectively turns the LPT port into "just a bunch of pins".

There was mention of this

mtest001 wrote on 2024-05-19, 12:36:

I did connect it to the laptop, then in the BIOS there is an option to indicate that an external FDD is present but it does not seem to have any effect.

So the bios detects it.
but, indeed that does not rule out that some wires might be faulty.

The best part is that no two vendors did the cabling the same way, often not even between different machines in the same line. So, the only way to know for sure is to either take the cable apart (destructive) and make your own brand new one that's a replication after, or find another unit that works with THIS machine, is known good in the first place and probe it out. Can we get pictures of both sides of the cable? It's possible the cable itself is a straight through DB-25 cable and the drive itself (or the computer) have an issue.

AngelaTheSephira wrote on 2024-05-20, 01:55:

weedeewee wrote on 2024-05-19, 21:13:

There was mention of this […]
Show full quote

AngelaTheSephira wrote on 2024-05-19, 21:01:

Note that when this is connected, that is no longer a parallel port at all, and the pinouts change. It's worth checking the cable itself for damage inside the connectors; it may be missing something that tells the computer to change the pinout and put 12V or 5V on some pin to power it.
It effectively turns the LPT port into "just a bunch of pins".

There was mention of this

mtest001 wrote on 2024-05-19, 12:36:

I did connect it to the laptop, then in the BIOS there is an option to indicate that an external FDD is present but it does not seem to have any effect.

So the bios detects it.
but, indeed that does not rule out that some wires might be faulty.

The best part is that no two vendors did the cabling the same way, often not even between different machines in the same line. So, the only way to know for sure is to either take the cable apart (destructive) and make your own brand new one that's a replication after, or find another unit that works with THIS machine, is known good in the first place and probe it out. Can we get pictures of both sides of the cable? It's possible the cable itself is a straight through DB-25 cable and the drive itself (or the computer) have an issue.

just an fyi, I'm not the OP of this thread.
Opening up the cable and fdd seems kinda futile if we do not have the actual wiring scheme it needs to have.
A photo of the underside of the FDD that shows the sticker mentioning which model compaq fdd it is will also be helpful if enough documentation can be found.

edit: Thanks to this Re: Compaq LTE Lite 4/33c parts, drivers and BIOS which leads to
this, https://web.archive.org/web/19991109002030/ht … es/us/1_23.html
there does not seem to be any drivers for the external floppy drive at first glance.

AngelaTheSephira wrote on 2024-05-20, 01:55:

Can we get pictures of both sides of the cable?

The other end of the cable, attached to the drive, is sealed in plastic. I'll also try to take a picture from below the drive to see if there is any useful indication.

I'm traveling right now so unfortunately that's going to take a bit of time.

In the meantime I thought maybe some settings in the BIOS need to be changed. In the BIOS there is an option that says "External Diskette Drive" (see below), I tried to change that to enable it but it did not work. Perhaps I also need to disable the parallel port?

You could also give fixing the internal drive a shot. It seems to be detected properly, the electronics should be ok.
In my experience, it's almost always simple mechanical problems when floppy drives go bad, like dried up lubricant, dust collected over the years clogging the mechanics, broken/stiffened rubber belts, etc. If you're lucky, just cleaning and relubricating it might be enough.

Thank you and yes, eventually I'll need to do that. But I am procrastinating because the case is quite fragile and every time I open it is an other occasion to break some of the tiny plastic latches...

weedeewee wrote on 2024-05-20, 06:52:

just an fyi, I'm not the OP of this thread. Opening up the cable and fdd seems kinda futile if we do not have the actual wiring […]
Show full quote

AngelaTheSephira wrote on 2024-05-20, 01:55:

weedeewee wrote on 2024-05-19, 21:13:

There was mention of this

So the bios detects it.
but, indeed that does not rule out that some wires might be faulty.

The best part is that no two vendors did the cabling the same way, often not even between different machines in the same line. So, the only way to know for sure is to either take the cable apart (destructive) and make your own brand new one that's a replication after, or find another unit that works with THIS machine, is known good in the first place and probe it out. Can we get pictures of both sides of the cable? It's possible the cable itself is a straight through DB-25 cable and the drive itself (or the computer) have an issue.

just an fyi, I'm not the OP of this thread.
Opening up the cable and fdd seems kinda futile if we do not have the actual wiring scheme it needs to have.
A photo of the underside of the FDD that shows the sticker mentioning which model compaq fdd it is will also be helpful if enough documentation can be found.

edit: Thanks to this Re: Compaq LTE Lite 4/33c parts, drivers and BIOS which leads to
this, https://web.archive.org/web/19991109002030/ht … es/us/1_23.html
there does not seem to be any drivers for the external floppy drive at first glance.

This is the reason I'd really like to not have to have them do that. But since it's encased in the plastic of the drive itself, there's no point in my thought of it being a straight-through DB-25 cable or the like.

Ok I'm back to my issue... Finally took the time to take more pictures.

I was wrong when I said the cable was sealed in the plastic, in fact the internals are fully exposed as you can see...

The part number says 135233-001 .

Just to be sure I'll try to disable the parallel port in the BIOS to see if it helps.

mtest001 wrote on 2024-05-24, 21:13:

Ok I'm back to my issue... Finally took the time to take more pictures. […]
Show full quote

Ok I'm back to my issue... Finally took the time to take more pictures.

I was wrong when I said the cable was sealed in the plastic, in fact the internals are fully exposed as you can see...

The part number says 135233-001 .

20240524_224836.jpg

20240524_224841.jpg

20240524_224852.jpg

20240524_224855.jpg

Just to be sure I'll try to disable the parallel port in the BIOS to see if it helps.

Yep, that looks like what I remember, you can even take the drive out and use it in an appropriate machine. like an armada m700.
The connector at the floppy side of the cable is the same as what is on the inside of the laptop.
It should just get detected when attached to the laptop for all I recall.
I'm guessing that the external drive you have is just not appropriate for your machine.