FSDE - Working with four floppy disc drives on the CPC.

[GUNHED]

Would you be interested to have four floppy disc drives on your CPC?

Imagine you could copy a DSK with big format (ParaDOS, ROMDOS, Vortex etc.) directly from HxC / Gotek to a real 3.5" disc. Or copy a 3.5" disc with 0.7 MB format at once. Or copy from 3.5" to 5.25" directly (without the need of moving anything through the 3" disc bottleneck).

A CPC could have / use at the same time:
- 3"
- 3.5" / 2nd 3"
- 5.25" / 2nd 3.5"
- HxC / Gotek

All at the same time!

Would you like to have such a thing?

[Sykobee (Briggsy)]

Certainly I can see it would be useful, especially with a drive A/B flip option (even if it switched C/D at the same time).


You would need your own drive interface design, so that you connected up DS1 on the NEC 765A. Maybe it's possible to mod the DDI-1 as well - pin 28 seems to be the unconnected pin. I guess you would need to modify AMSDOS / PARADOS / etc as well to be able to select more drives.


Dunno if the DDI-3/4/etc have done this.


Dunno either if Gotek has dual-drive support yet (i.e., supports being two drives on a bus, with different images selected for each).

[GUNHED]

The idea of FSDE is to have only minor changes inside the CPC, but to have a small external board with plugs for three drives B, C and D.

I won't be needed to change the known DOS or OS.  Because most of them only target drives A and B. Drives C and D are only used by DDOS for CPC464 (and one other OS).

For the DDI-1 it's doable too.

[Bryce]

I don't need one myself, but others might have a use for one.

By the way, there's a way of doing it without changing anything inside the CPC

Bryce.

[VintageAdvantage]

Would you be interested to have four floppy disc drives on your CPC?

Why the f*** would you care if anybody on this forum is interested in your hardware development.
You will neither get rich nor famous. Just build your thing and sell it on eBay.
Done. Remember - it is YOUR hobby, and you are DOING IT FOR YOURSELF. Not for others. 

[GUNHED]

Why the f*** would you care if anybody on this forum is interested in your hardware development.
You will neither get rich nor famous. Just build your thing and sell it on eBay.
Done. Remember - it is YOUR hobby, and you are DOING IT FOR YOURSELF. Not for others.

Well, I lived 8,5 years and 9 days in the USA (NOLA) so I did learn a bit about the US philosophy. And it's not mine and it will never ever be.

Nevertheless I try to provide an answer.

The reason to ask such questions in a bigger (talking about the number of members) forum is to be able to assess the common interest on such a project. I do have many projects on my mind, but only limited time. Therefore I try to pick (out of a bunch of projects of nearly equal importance to me) one project which is of common interest. This means I will realize a project if it is of higher common interest.

Furthermore I'm not interested in "get rich nor famous", "sell it on eBay" and many other lower things.

[Kris]

Hi all,


Currently, i'm already using 4 storage devices on my CPC: drive A (3"), drive B (gtoek), m4 card and its SD support and a X-mass 512Mo.
Using IMPdos ROM, I already can copy anything from a drive to another one, copy big files from the SD to the X-mass and revert etc....


The idea is fun but there is no need on my side.

[VintageAdvantage]

Currently, i'm already using 4 storage devices on my CPC: drive A (3"), drive B (gtoek), m4 card and its SD support and a X-mass 512Mo.

ok

[GUNHED]

Alright, seems the interest is quite minimal. So no need to follow up this project too much. Will put it aside and assign priority to other projects. 

[Skunkfish]

I'd be quite interested in this if there's an easy way to redefine which is A/B...

[GUNHED]

I'd be quite interested in this if there's an easy way to redefine which is A/B...

You would set the jumpers DS0, 1, 2, and 3 on the floppy disc drive.


All runs using a "2 to 4" decoder on a small external PCB right after the Disc Drive 2 port. Looks like a dongle ;-)
The advantage is that inside the CPC is less to resolder. Other solutions make that all internal, which needs quite some more soldering inside the CPC. 

[VintageAdvantage]

How are you going to select / switch the drives? Output control voltages over the printer port, or something more fancy?
(And then you will need patches to existing software to switch the drives  - don't you think mechanical switches would be better?)

[GUNHED]

How are you going to select / switch the drives? Output control voltages over the printer port, or something more fancy?
(And then you will need patches to existing software to switch the drives  - don't you think mechanical switches would be better?)

Mechanical switches will not allow to use more than two drives at a time. The point is to be able to access four drives at the same time.

Drives B, C and D will be connected to the Drive B port. However between the drive B port of your CPC and the new drive BCD port, there will be a small PCB enabling drives  B, C and D instead of B only.

About software, there is at least one DOS (the DDOS) which does support four drives. No patches are needed. For other DOS simple patches may be needed though.

[Audronic]

By the way, there's a way of doing it without changing anything inside the CPC
Bryce.

Hi Bryce


Do you have a link to the 4 Drive solution.


Thanks. Ray

[Bryce]

No, I don't think anyone has ever released or uploaded a solution.

Bryce.

[ComSoft6128]

Hi Bryce


Do you have a link to the 4 Drive solution.


Thanks. Ray

Hi Ray,


While combing thru the Australian CPC mags a few months ago I ran across a 4 drive project in an issue (2 issues?) of one (CWTA?) of them. As hardware is not my thing I didn't read it or take note which magazine it was in   but there definitely was one. If you have some (a lot) of spare time you might want to look thru them, might.

[Audronic]

Ok Thanks.
Some thoughts in the picture.

[Audronic]

Hi Ray,

While combing thru the Australian CPC mags a few months ago I ran across a 4 drive project in an issue (2 issues?) of one (CWTA?) of them.

Hi ComSoft6128. Do you have a link for the Mags. Thanks.  Ray

[ComSoft6128]

Hi Ray,


Here's a start:


https://www.classic-computers.org.nz/bits-and-bytes/index.htm


But I'm leaning towards CWTA (11 issues) or TAU (80 issues) and I can't remember where I downloaded them from


Cheers,


Peter

[Audronic]

Hi Peter


Thanks I will have a look


Keep Safe




Ray

[archcosmo]

No, I don't think anyone has ever released or uploaded a solution.

Bryce.

Hi Bryce
Apologies for the intrusion - but this topic rings bells, because I've got a mod much like this installed in one of my 6128s. really useful back in the 80s/90s for swapping 5.25" or 3.5" floppies at computer club meetings etc

Anyway - we swapped a couple of messages (or PMs?)  many years ago about getting a Lotharek SD floppy emulator working with a DriveSelect switch mod I'd posted about in the forum and some references to the "Amstrad Technical Magazine" disk-mag. You'd provided me with tips and a work-around circuit fix to restore some broken/missing signals, that this mod didn't include! Thanks again!

the mod is described in ATM issue 3 .. Basically its an extension of the ABBA mod but also enable the external drive select lines (DS0-4) to be set to Drive A,B or Disable.. worked ok for real floppy drives (disk-to-disk copy!), but not with floppy emulators.
one the thumbnail pictures here on CPC Power shows what the mod I'm talking about

https://www.cpc-power.com/index.php?page=detail&num=12569

hope this helps

[Bryce]

Oh, I remember that. That was a long time ago. That system relied on the user to manually switch between drives though. The discussion here is more about getting the system to recognise all four at the same time so that the computer has a "C" and "D" drive too.

Bryce.

[GUNHED]

My idea to enable four drives in parallel would only need to solder one simple wire inside the CPC. Anything else would be located outside of the the CPC on a tiny board between the disc-drive-2 socket  and a cable with plugs for drives B, C and D.