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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: Caterman on 23:37, 02 November 19

Title: PCW 8512 - Disable B Drive
Post by: Caterman on 23:37, 02 November 19
I have a Gotek installed as A drive but with a  semi-faulty B drive it is a little annoying that I have to have a 3" floppy in the B drive for Locoscript to try to read and fail. I cannot run Locoscript without a disk in the B drive. Is there a way to disable the B drive and just run with the A Drive?
Title: Re: PCW 8512 - Disable B Drive
Post by: GeoffB17 on 00:43, 03 November 19
This sounds rather odd.

What happens when you start CP/M with no disk in B:?   Does that give any sort of message, and demands a disk?   When you get the initial message for CP/M, does it say there is one drive A: or two?

With my PCW8256 (but with the extra RAM) I have no normal B: drive.   Instead, I have a 5.25" drive, and with that, if there is no disk in the drive, then CP/M decides that the drive is not there and proceeds as if there is A: only.   I believe that it does the same using Locoscript.   I also have a 3.5" drive B: attached, and that is wired to be 'ready' always.  CP/M starts normally, the drive is detected, and disregarded until a disk is inserted, whereupon it is accessed normally.   I confess I've never tried Locoscript with just A: and B:, but when I've booted into Loco with A: and the uIDE drives C: onwards then Loco sets off to access the extra drives but doesn't bother with B:.

What is actually wrong with the B: drive?   Maybe there is something that gives the impression that there IS a disk there?

What version of Locoscript are you using?  Is it a version intended for the 8xxx series?

What happens if you disconnect the B: drive totally inside (power and data)?   If you're not planning to fix the drive, you might as well esp if it's causing problems.

Geoff
Title: Re: PCW 8512 - Disable B Drive
Post by: GeoffB17 on 18:30, 03 November 19
Further...

I've found an old Start of Day disc for Loco 1.31, with no FID for using the uIDE drives, and started up with no disk in B:.   Loco starts up OK, but states that drive B: is not present.   This seems consistent with what happens with CP/M.   If a disk is inserted into B: for reboot, then B: is recognised and read as usual.

So, with your machine, it seems that B: is being detected as 'ready' as if there is a disk in, even though there is not.  Loco is trying to access/read the disk.   As you describe, this situation is resolved by inserting a disk, although due to other (or the same) problems the disk cannot be read properly.

I assume by the way that you do have B: format disks available to be read?   Although I think that the 8512 CAN READ an A: format disk in the B: drive, but I'm not sure if it can do that immed at the point of startup.

Geoff
Title: Re: PCW 8512 - Disable B Drive
Post by: JohnElliott on 23:07, 03 November 19
I don't know if it's any help in this case, but I've got a DISABLEB.FIB file from a PCW9256 startup disk. If your version of CP/M or LocoScript supports .FIB files, this will deactivate drive B: and the system will behave as a single-drive PCW.
(An oddity: It's got two different sign-on messages. "Drive B: disabled" for CP/M, but "Drive B: Disabled" for LocoScript).
Title: Re: PCW 8512 - Disable B Drive
Post by: Caterman on 15:53, 04 November 19
Initial testing
I haven't got a correctly formatted disk for drive B as when I try to do a format it shows a disk protected error.
I do believe there is a problem with Drive B


Locoscript v1.0 CPM1.1 - with no disk in drive B startup stalls
With a disc in drive B you get an error Disc Manager - Disc address mark missing and I cannot cancel out of this and continue loading Locoscript


CP/M Plus v1.1 61K TPA 2 disc drives, 368k Dive M: no difference with disc in drive or not

Locoscript v1.2 - with no disk in drive B startup stalls
With a disc in drive B you get an error Disc Manager - but you can get passed by cancelling operation. Locoscript then continues and loads


CP/M Plus v1.4 61K TPA 2 disc drives, 368k Dive M: no difference with disc in drive or not


I'm worried it may have something to do with the gotek in drive A.
I might try and get the original drive A working.



Title: Re: PCW 8512 - Disable B Drive
Post by: GeoffB17 on 19:48, 04 November 19
Why do you get a 'disk protected error'?   This is odd.   I assume the actual disk is not protected?

Is this drive a high capacity drive (i.e. 720k)?   Has it previously worked correctly?   I know the original version 178k (A:) drives used a mechanical write protect pin which could come out, I'm not sure if the later B: type drives worked the same way or used a LCD type detector.   Maybe the detector is clogged with muck and isn't working properly?

If the drive IS a correct B: drive, and you try to give it an incorrectly formatted disk at startup then this will cause a problem that will be fixed as soon as you have a correctly formatted disk to use.

There are things built into the system software that assume that the A: drive (and the boot drive) is SS, and the B: drive is DS, and errors could be generated if this seems NOT to be so.   The use of the Gotek might confuse this.   I assume you're booting using a SS image.

There are slight differences between different versions of the system, esp the versions you have, regarding how they detect/verify the drives, as Amstrad were getting the problems sorted regarding users getting the disks the wrong way around.

However, you do seem to have a problem regarding your B: thinking that there IS a disk present when there is none.   I don't think this problem would be connected with the Gotek.

The error you refer to re 'disc address mark' certainly indicates a wrong format, i.e. the disk you're using is not a B: format, and might even be worse than that.   As I noted before, the B: drive should be able to read an A: format disk, although it may NOT be able to do this at boot stage.   Actually, the disk might even be totally blank, i.e. not formatted at all.  Do you have other disks, or any known to be formatted (even if A:)?

There are other people on this forum using the Gotek device, without any problems, and I think that includes with a B: drive.

By the way, regarding the message from John Elliott, the system versions you have do NOT support .FIB/.FID files, so you could not use the DISABLEB file he mentions, butyou could find versions of the system that DO allow this.

Geoff
Title: Re: PCW 8512 - Disable B Drive
Post by: GeoffB17 on 01:22, 05 November 19
Also...

Further to the mention of DISABLEB, I've just checked my files .DSK system files, and I see an image marked as for a PCW 9512.   When I look inside the image, I see a copy of DISABLEB.FIB, also the image includes the system file J25CPM3.EMT which I'm sure will be capable of handling the .FIB file.

Geoff
Title: Re: PCW 8512 - Disable B Drive
Post by: Caterman on 11:08, 05 November 19

Thanks for all your contributions, but the route of the problem is the Gotek somehow.
Repaired a 3" drive A and I can now read a cp/m disk in B

You say people do have a Gotek paired with a 3" B drive

Can anyone confirm what the jumpers should be
I have MO and S0 jumpered.
Title: Re: PCW 8512 - Disable B Drive
Post by: JohnElliott on 11:09, 05 November 19
You should not have MO jumpered in a two-drive system - it's making the Gotek respond as A and B. Just S0 should be sufficient.
Title: Re: PCW 8512 - Disable B Drive
Post by: Caterman on 12:28, 05 November 19
Removed M0 still no joy with Drive B
Title: Re: PCW 8512 - Disable B Drive
Post by: torrind on 19:39, 06 November 19
I  have twin Goteks as drive A and B - And only 1 jumper on each. A is set to S0 and B set to S1 and that's it. M0 and all the others aren't connected.
Title: Re: PCW 8512 - Disable B Drive
Post by: TynH on 21:43, 06 November 19
Quote from: JohnElliott on 11:09, 05 November 19
You should not have MO jumpered in a two-drive system - it's making the Gotek respond as A and B. Just S0 should be sufficient.


Hmm that's exactly how my drive B behaves. Makes considerable noise with or without a floppy during boot but only seems to read drive A.

Where's this jumper thing anyway?

I've been thinking about upgrading to a double Gotek setup, but not sure how to make that work. Plus I'd lose the ability to read floppies (although that's not working now either). With my uIDE hdd it would be a slightly expensive exercise too.
Title: Re: PCW 8512 - Disable B Drive
Post by: Caterman on 10:28, 07 November 19
M0 was one of the problems the other 2 were a defective B Drive and 3 out of my 4 Floppy Disks FUBAR as well.
Got another Gotek and now working like a charm.
I have now got the original Drive B working problem was everything was write protected so couldn't format a floppy for PCW.
Turns out problem was with Q3 DTC114YK - Anyone know where to get one.
Currently rigged the drive so it ignores the write protect!!!!


Attached a couple of photos.

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