Re: [hatari-devel] IKBD regression with EmuTOS

[George Nakos <ggn@xxxxxx>]

Hello Vincent,

Sunday, February 10, 2013, 8:29:57 PM, you wrote:

> On 10/02/2013 18:08, Nicolas Pomarède wrote:
>> looking at the reset sequence,

> Thanks for your analysis, Nicolas.

> The main oddity is that EmuTOS works fine on real hardware (STe and Falcon),
> while it doesn't in the latest Hatari. So I suspect an inconsistency in Hatari.

I haven't taken a look at the EmuTOS sources in years, so I'm not sure
how  it's  handling the IKBD reset, but I do know that if you send any
command  during  the  IKBD  reset (i.e. within 300ms after issuing the
reset  command)  it  gets ignored. Maybe there's a deliberate pause in
EmuTOS?

Proof:  http://pouet.net/prod.php?which=60836,  which  I  debugged for
!Cube.  He  was  doing  what  I  described  above, so his "kill mouse"
command  was  being  ignored  by  real hardware, while it worked ok on
STEem (and possibly hatari).

> Also, on Hatari, I don't understand why it works fine after Reset, since the
> EmuTOS initialization code is the same.

>> It then sends the following bytes to the ikbd : $80, $01, $1a, $12.
>>
>> This resets the keyboard

> Yes.

>> and sends $1a and $12 *during* the reset,

> Do you mean that we send $1a and $12 too early after the reset?
> Do we have to wait a bit?

>> which put the ikbd in a mode where it reports both mouse and joystick. Is
>> this really intended ?

> Yes, we expect to receive mouse and joystick packets.

>> But the main problem could be that after the ikbd reset, you will receive a
>> byte $f1

> Really? I don't see that in "Le livre du développeur".

>> Can you describe what emutos is supposed to do to handle this $f1 byte ?

> Currently, AFAIK EmuTOS does not expect that $f1 byte.

>> When comparing with tos 1.04 for example, it sends only $80 and $01 and read
>> $fffc02 to clean the RDRF bit.

> Ok, EmuTOS will need fixing if $80 $01 really answers with $f1.
> But that does not explain why it works fine on real hardware.




-- 
Best regards,
 George                            mailto:ggn@xxxxxx