Re: [hatari-devel] LED with empty floppy drives

[David Savinkoff <dsavnkff@xxxxxxxxx>]

----- Nicolas Pomarède wrote:
> Le 03/05/2014 21:31, David Savinkoff a écrit :
> > I believe TOS has a timeout that turns off the floppy motor And led.
> > Maybe internal floppy STF 520 differs from external floppy ST 520
> >
> 
> Maybe depending on the TOS version, but I'm not sure.
> 
> My 520 STF tos 1.02 doesn't turn it off, and I just checked with a 520 
> STE (tos 1.62 I guess) :
> 
>   - 1 internal drive A and 1 external drive B
>   - boot on A, wait for desktop
>   - eject A, click on A icon and click on cancel when TOS says it can't 
> access disk -> led and motor remain on until a floppy is inserted (no 
> timeout)

520ST+SF354(A:)+TOS1.00 ->  led and motor remain turn off (timeout)

>   - same on B : drive B is empty, click on B icon, click cancel on the 
> TOS message that appears -> led and motor remain on until a floppy is 
> inserted in B (no timeout either)

520ST+SF354(B:)+TOS1.00 ->  led and motor remain turn off (timeout)

> So, either TOS 1.00 had a different behaviour (with a timeout) or it's 
> the SF354 drive, but for me the common behaviour is the one I described 
> above.
> 
> 
> Nicolas
>
I'm curious to know how the floppy LED is implemented in the STF.
Is the LED connected to the M51017AP IC, or is it connected to
something else?
Note that the LED is connected to the M51017AP 'in use pin'
in the SF354.
Note that the external double sided SF314 is probably very similar
to the SF354... and the LED stays on.

Maybe Atari TOS has a M51017AP 'in use' Bug for double sided disks.
Note that EmuTOS can be made without this bug.

Hatari may have to emulate when the floppy disk is busy by checking
the floppy disk bus lines to know when the LED is on.