>> I've been using this routine blindly for some time and it works, but I'd
>> like to know exactly the electrical reasons behind the process.
>
>**sigh** okay I'll explain...
>
>By the way, the AND and ORs you say belong to port 2 belong to port 1. You
>accidentally (I hope?)swapped them.
I'm aware. This listing is pasted "as is" from the Portar docs.
>Well, bit 6 is used as port select for register 14. (1=port 2, 0=port 1)
>Bit 0, 1 and 4 correspond to pins 6, 7 and 8 of port 1
>Bit 2, 3 and 5 correspond to pins 6, 7 and 8 of port 2
>
>Well, here are the reasons why they are set: officially, the joystick only
>works when pin 8 is 0. So the joystick-routines set the pin to 0. Further,
>pins 6 and 7 only give input as long as the output is 1. So in order to read
>pins 6 and 7 they first set them.
Aaaah. That's neither explained on Portar nor The Red Book.
> Ofcourse this won't have to be done
>everytime, but if they for example don't set bits 6 and 7 then if some nerdo
>changes bits 6 and 7 into 0 the buttons can't be read anymore until the next
>reset.
Nice.
>Well that's the reason.
Thanks.
>By the way, the joystickroutines on the interrupt also (re)set those pins,
>unfortunatly. And that is stupid because therefor JoyNet can't function with
>the normal interrupt enabled.
Something to do with touchpad handshaking, perhaps?
MARK 2
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