VOGONS


First post, by dadocastro2801

User metadata
Rank Newbie
Rank
Newbie

I'm trying to boot an amstrad pc1640 SD with a system floppy disk but it won't boot
I have tryed with 2 floppy drives and 2 flopy disks
Any ideas?

Reply 1 of 4, by MarkTheMorose

User metadata
Rank Newbie
Rank
Newbie

We could probably use a bit more detail.

Presumably, the computer is powering-on; do you get any screen prompts? Do the floppy drives sound like they are trying to spin? How long since this machine last booted from a floppy disk correctly?

Reply 2 of 4, by kdr

User metadata
Rank Member
Rank
Member

If the floppy drives and media have been in storage for a while (sounds likely) you'll probably need to clean the magnetic heads in the drives and also clean the surface of the magnetic media inside the floppies. You may also need to clean and then lubricate the metal rails inside the drives; this is what the head assembly moves back and forth on, and too much friction can prevent the drive from seeking to the correct track.

In my experience 5.25" 360KB drives and media are pretty reliable (unlike 3.5" 1.44MB floppies) but it's tricky to proceed if you don't have any known good drives and also don't have any known good floppies.

And even if you have a working floppy drive and a working bootable floppy diskette, there could still be other issues with the Amstrad that prevent it from booting properly...

Do you have an old PC with a floppy drive header on the motherboard? Even an XP era machine should still have BIOS support for 5.25" 360KB floppy drives. You could hook up one of the drives to it and see if anything can be read off the floppies.

Reply 3 of 4, by BitWrangler

User metadata
Rank l33t
Rank
l33t

Amstrad original media, the DOS, GEM and DOS+ disks were known for going bad 5-10 years out, at 30ish years old they may not be any good unless they're practically new.

kdr wrote on 2021-12-11, 02:57:

Do you have an old PC with a floppy drive header on the motherboard? Even an XP era machine should still have BIOS support for 5.25" 360KB floppy drives. You could hook up one of the drives to it and see if anything can be read off the floppies.

Amstrad drive ID etc is set up more like Shugart standard than IBM's perverted version of standard, so while Amstrad drives can be got to work with IBM PC interfaces, it's gonna confuse the hell out of our friend here. Take cellphone pics of the jumpers before you start messing around. I think maybe the B drive will work on the A position of an IBM standard cable, can't remember if motor select needs messing with. Unless the problem in the first place is that drives set up for IBM have been put in the Amstrad and not set up for the Amstrad.

Edit: details here... https://www.seasip.info/AmstradXT/hwcompat2.html however to understand that you have to know that IBMPC floppies are NOT set as drive A, or first drive ID, they are set to the second drive ID by default, depending on the drive, if IDs are 0, 1, 2, 3 that means it's set to 1, if it's 1, 2, 3, 4 it's set to 2. To work as drive A in the Amstrad it actually has to be set to drive A, the first drive, so 0 if starting from 0, 1 if starting from 1... some drives may not have a jumper block but only a 0-1 switch or similar.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 4 of 4, by kdr

User metadata
Rank Member
Rank
Member
BitWrangler wrote on 2021-12-11, 03:53:

Amstrad drive ID etc is set up more like Shugart standard than IBM's perverted version of standard, so while Amstrad drives can be got to work with IBM PC interfaces, it's gonna confuse the hell out of our friend here. Take cellphone pics of the jumpers before you start messing around. I think maybe the B drive will work on the A position of an IBM standard cable, can't remember if motor select needs messing with. Unless the problem in the first place is that drives set up for IBM have been put in the Amstrad and not set up for the Amstrad.

Oh that's interesting, I had always thought the Amstrad PC1512/1640 were just IBM compatibles with a nice Amstrad logo on the front. Agreed that if the drives aren't jumpered for standard PC usage (I think it's DS1 although I've never actually needed to change a floppy jumper before) then it could be quite confusing trying to get them going on a standard PC.