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Falcon A & B floppy.

Posted: 05 May 2023 23:57
by Rustynutt
Something I'd never thought about until assembling a MKX case.
Can one of those fancy floppy emulators be set to slave, and a regular 3.5" HD as master floppy be on the same cable?

Re: Falcon A & B floppy.

Posted: 06 May 2023 07:13
by HigashiJun
You mean drive A: is FDD and drive B: HXC or Gotek ?

I had this setup in my STE and both drives worked flawlessly.

I just crimped my FDD flat cable, connected my drives and set-up my HXC as unit B:

I guess the Falcon will also allow that kind of configuration.

Re: Falcon A & B floppy.

Posted: 06 May 2023 07:46
by frank.lukas
See the Falcon schematics there is only Driveselect_0 connected at the PSG. So one A Drive only. I not kow Falcon TOS can handle a drive B ?

Re: Falcon A & B floppy.

Posted: 06 May 2023 17:42
by Rustynutt
Thank you both. The ST line was always able to handle 2 floppy drives, but wasn't sure if the Falcon could.
The only other Falcon "B" drive I've ever testing was a SCSI floppy disk. It worked, but system not recognizing as a drive "B".
Uwe just shrugged :)
It's not big idea. Maybe a toggle switch to change between the two.

Re: Falcon A & B floppy.

Posted: 06 May 2023 18:11
by frank.lukas
Falcon_PSG.jpg


IOA 0 = S0SEL
IOA 1 = DriveSelect 0 (Floppy A)
IOA2 = n.c. (Driveselect 1 at all Atari ST Computer /Floppy B)

Re: Falcon A & B floppy.

Posted: 06 May 2023 18:22
by Rustynutt
So IOA2 not utilized on Falcon in hardware.
Think next step is how TOS 4 handles drive B request. It must only look for disk change, and not hardware I think.

Maybe Hatari user with dual floppy can confirm this.

Re: Falcon A & B floppy.

Posted: 07 May 2023 04:19
by HigashiJun
frank.lukas wrote: 06 May 2023 18:11 Falcon_PSG.jpg



IOA 0 = S0SEL
IOA 1 = DriveSelect 0 (Floppy A)
IOA2 = n.c. (Driveselect 1 at all Atari ST Computer /Floppy B)

Good one !

So it seems there is no way to fit 2 internal drive units in the Falcon...

Re: Falcon A & B floppy.

Posted: 07 May 2023 05:39
by Rustynutt
Wasn't a big deal. Perhaps looking at an ST(e)/Mega/TT schematic, the pin could be traced, but imagine like Frank says TOS 4 likely wouldn't know what to do with it.
Was just looking to fill a hole in the case :)
And..not give up my floppy disk drive. Could never do that :)

Re: Falcon A & B floppy.

Posted: 07 May 2023 05:44
by stephen_usher
You could put a hack on the cable side of things by taking a leaf out of the Apricot F Series machines. Put an inverter on the Drive 0 select line to generate a drive 1 select. In other words, if drive 0 isn’t selected then drive 1 is. You never know, TOS may still have the code to test for the drive due to there being no need to remove it and laziness.

Re: Falcon A & B floppy.

Posted: 21 Dec 2024 19:38
by foft
Did any of you give this a try? i.e. inverter or connecting that PSG line manually?

Just getting round to putting my Falcon motherboard back in the Space Case and thinking it'd be nice to have Gotek and Floppy!

Guess I can scope that IOA2 PSG pin if not to see if anything happens if I click on drive B on the desktop...