Errius wrote on 2020-02-09, 22:16:

Right, so it has two 5.25" floppy drives and you want to add an external 3.5" drive. Does it have a hard disk?

If you have another DOS machine with a 3.5" drive you can connect them via parallel cable and transfer files that way.

Well I wanted to add the external drive to a modern pc that does have usb support (my 98 pc or something) and then transfer the written floppy to the commodore.. my pipe dream was that there would be USB models just as there are for 1.44" diskettes but that seems a big no go. I do have a 386 with a diskette drive but not a floppy 🙁

No, as others have said, USB 5.25" floppy drives were never made. (I think there are specialist devices for archiving of old disks, but they are very expensive.)

Disk drive density is also an issue. I see the PC10 has 360 KB (double density) drives. Most 5.25" drives on sale on places like eBay are 1.2 MB (high density). DD disks written on HD drives won't read properly on DD drives.

You have 3 options that I see:

1) Install an external 3.5" parallel port drive in your XT, and a regular USB floppy drive on your main rig, and transfer files that way.

2) Copy the files to your 386 and then transfer them to your XT with a parallel cable

3) Install a DD (not HD) 5.25" drive in your 386 and use it to create disks readable in the XT

Errius wrote on 2020-02-09, 22:35:

No, as others have said, USB 5.25" floppy drives were never made. (I think there are specialist devices for archiving of old dis […]
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No, as others have said, USB 5.25" floppy drives were never made. (I think there are specialist devices for archiving of old disks, but they are very expensive.)

Disk drive density is also an issue. I see the PC10 has 360 KB (double density) drives. Most 5.25" drives on sale on places like eBay are 1.2 MB (high density). DD disks written on HD drives won't read properly on DD drives.

You have 3 options that I see:

1) Install an external 3.5" parallel port drive in your XT, and a regular USB floppy drive on your main rig, and transfer files that way.

2) Copy the files to your 386 and then transfer them to your XT with a parallel cable

3) Install a DD (not HD) 5.25" drive in your 386 and use it to create disks readable in the XT

I'll research a bit on the second option, which seems the easiest to achieve. Never done this however, it is as simple as connect the two machines and.. ?

Does your PC10 have a hard drive? If it doesn't, and you don't intend to install one, option 3 is probably the best. 360 KB doesn't leave you with much elbow room.

The issue of transferring files between computers via cables came up in this topic: Interlink for DOS

Errius wrote on 2020-02-09, 23:31:

Does your PC10 have a hard drive? If it doesn't, and you don't intend to install one, option 3 is probably the best. 360 KB doesn't leave you with much elbow room.

The issue of transferring files between computers via cables came up in this topic: Interlink for DOS

It does have a hard drive, 10 full mb!

Good, that simplifies things. Before you do anything else, get a null modem serial cable with 9-pin to 25-pin adapter. Once you have the serial connection working you can also get a parallel cable for greater speed. There are detailed instructions in that link I posted.

You don't have to use the 386 for this. Any DOS/Windows 9x computer with serial and parallel ports will work.

What about an easier solution such as a XT IDE card and then use an IDE to CF card adapter that has easy access through a slot on the back of the XT?

Then you could just use a CF usb adapter on the newer computer.

Then you just copy stuff to the CF card on the newer computer and access that directly with the XT?

No need to deal with floppy drives or floppy disks at all.

Do you have a Commodore 1571 drive in your collection? It can write MFM MS-DOS disks.

http://biosrhythm.com/?p=1680

Another thing the OP can do is simply transplant the XT hard drive and controller card into another computer, taking care to jumper it for drive D: so it doesn't conflict with the host drive.

OMG... no comment on some comments here...

So it's about a Commodore PC of the XT class and data exchange with a modern PC... Easy...

You need:
1. Parallel Port ZIP drive
2. USB ZIP drive
3. A few 100 MB ZIP medias
4. MS-DOS 5 or better on that XT
5a) A NEC V20 CPU if your Commdore PC has an 8088 at same clock frequency
5b) A NEC V30 CPU if your Commdore PC has an 8086 at same clock frequency (don't think so)
6) IOMEGA's GUEST.EXE driver (which ueses some 80186/286 instructions which are not available on 8088/86, but on V20&30.

1+2+3+4+5b+6 is the way I do it with my Olivetti M21/24/24SP,240. It works quite nice.

1ST1 wrote on 2020-02-10, 21:42:

OMG... no comment on some comments here... […]
Show full quote

OMG... no comment on some comments here...

So it's about a Commodore PC of the XT class and data exchange with a modern PC... Easy...

You need:
1. Parallel Port ZIP drive
2. USB ZIP drive
3. A few 100 MB ZIP medias
4. MS-DOS 5 or better on that XT
5a) A NEC V20 CPU if your Commdore PC has an 8088 at same clock frequency
5b) A NEC V30 CPU if your Commdore PC has an 8086 at same clock frequency (don't think so)
6) IOMEGA's GUEST.EXE driver (which ueses some 80186/286 instructions which are not available on 8088/86, but on V20&30.

1+2+3+4+5b+6 is the way I do it with my Olivetti M21/24/24SP,240. It works quite nice.

But how do you get GUEST.exe on the Commodore without using an intermediary machine with 360k floppy drive?

Doornkaat wrote on 2020-02-11, 03:30:

But how do you get GUEST.exe on the Commodore without using an intermediary machine with 360k floppy drive?

Good question !

1ST1 wrote on 2020-02-10, 21:42:

You need: 1. Parallel Port ZIP drive 2. USB ZIP drive 3. A few 100 MB ZIP medias 4. MS-DOS 5 or better on that XT 5a) A NEC V20 […]
Show full quote

You need:
1. Parallel Port ZIP drive
2. USB ZIP drive
3. A few 100 MB ZIP medias
4. MS-DOS 5 or better on that XT
5a) A NEC V20 CPU if your Commdore PC has an 8088 at same clock frequency
5b) A NEC V30 CPU if your Commdore PC has an 8086 at same clock frequency (don't think so)
6) IOMEGA's GUEST.EXE driver (which ueses some 80186/286 instructions which are not available on 8088/86, but on V20&30.
1+2+3+4+5b+6 is the way I do it with my Olivetti M21/24/24SP,240. It works quite nice.

🤣 that is a whole lot of hardware that can be easiliy simplified by other methods....

Horun wrote on 2020-02-11, 04:01:

🤣 that is a whole lot of hardware that can be easiliy simplified by other methods....

Yes, but other methods are not RETRO. And don't forget, ZIP drive is hotswap. XT-IDE with a CF card is not. You always have to switch off for a swap. Serial connection is quite slow. And the fast modes of laplink, fastlynx, norton commander parallel port transfer don't work on many XT class machines as their parallel port is not bidrectional.

And, yes, guest.exe must be initially transfered to the XT, so you need a 360 kb diskette once, or serial cable.

What about installing a NIC in the XT and then spin up a local ftp server on the more modern machine.

https://www.brutman.com/mTCP/mTCP_FTP.html

Is it possible to send an arbitrary file across a serial connection using only stock DOS commands?

Errius wrote on 2020-02-12, 19:52:

Is it possible to send an arbitrary file across a serial connection using only stock DOS commands?

Just looked it up and it looks like you can by:

1. initialize the COM ports on both machines.
2. use the copy command.

Example:

Receiving computer:

1MODE COMx:2400,n,8,1,p
2CTTY COM1
3copy /b COM1: mygame.exe

Sending computer:

1MODE COM1:2400,n,8,1,p
2CTTY COM1
3copy /b mygame.exe COM1:

See here for a more in-depth discussion:
https://groups.google.com/forum/#!topic ... j6VserwN8

You will of course need a null modem cable or straight through cable and a null model adapter.

On the USB 3.5" part of this, I did find a guy on ebay last year that was selling NOS Dell external 3.5" USB external drives. I got one of them as they were like $15 shipped and can confirm that it was able to reach 720kb diskettes fine. Something that 2 other USB floppy drives I've bought over the years refused to do.

But even in my XT/286 days in the late 80s I don't ever recall seeing an external 5.25" or even an external 3.5" drive. All the XTs I worked with had 2 drives in them and my 286 had one of each installed internally both HD variants.

OT, but this reminds me of one of my machines, which is dual boot Windows XP and Windows ME. It has a DD (not HD) 5.25" drive installed which works fine in WME but which does not work in WXP. (I get an I/O device error when accessing the drive.)

Was support for these drives dropped in Windows XP?

Errius wrote on 2020-02-12, 21:08:

OT, but this reminds me of one of my machines, which is dual boot Windows XP and Windows ME. It has a DD (not HD) 5.25" drive installed which works fine in WME but which does not work in WXP. (I get an I/O device error when accessing the drive.)

Was support for these drives dropped in Windows XP?

Yes general support for the old 360k and 720k drives was dropped in XP. Somewhere I saw a patch that put it back in but that was years ago and was a Explorer + system hack of some type.

I don't own any 720 KB 3.5" drives. Do these have the same compatibility problems with 1.44 MB 3.5" drives that 360 KB 5.25" drives have with 1.2 MB 5.25" drives?

Can you write 720 KB disks in 1.44 MB drives and read them without errors in 720 KB drives?