Re: [hatari-devel] Re: Hatari floppy drive detection with EmuTOS

[David Savinkoff <dsavnkff@xxxxxxxxx>]

----- Roger Burrows wrote:
> On 16 Jan 2014 at 18:50, Nicolas Pomarède wrote:
> > Le 16/01/2014 18:28, Roger Burrows a écrit :
> > > On 16 Jan 2014 at 10:46, Nicolas Pomarède wrote:
> > >>
> > >> Do you have the possibility to test this on a real ST :
> > >>    - connect drive A and disconnect drive B as above
> > >>    - but in the drive detection test, test drive B first, then drive A.
> > >>
> > >> I'd like to know the delay you get in that case where spinup is made
> > >> first on the disconnected drive.
> > >>
> OK, the following runs were made with floppy 1 tested first, then floppy 0.
> 
> 1. Drive 0 connected, drive 1 disconnected:
>   Drive 1: timeout (3 seconds)
>   Drive 0: 255 ticks
> 2. Both drives connected
>   Drive 1: 361 ticks
>   Drive 0: 26 ticks
>
Hi Roger.
Are these tests done without floppy disks in the drives?
What model are your floppy drives?
> 
> For some reason, the timeout is working as expected here ...
> 
> On a related topic, I looked at your disassembly of TOS code.  It seems that
> TOS delays for approximately 60 microseconds before and after accessing the
> command/status register (I'm assuming a clock speed of 8MHz).  I have two
> questions:
> 1. What is the minimum delay necessary?
> 2. Is this delay the same for any FDC register access (e.g. track register)?
> 
> I ask because EmuTOS currently delays just 3 microseconds.
> 
> Roger
> 
> 
>