As you can imagine we run into pretty weird problems at points, one of them
being the shadowing of the YM2149 registers on the ST (not present on the
FYI, this is already done by TOS. Even on ct60 TOS Didier did this. So no problem here (whole 0x00FFxxxx area is already "mirrored" on 0xFFFFxxxx)
Falcon). The course of action we're following now is to patch the offending code
and get on with it, but this can prove tiresome and repetitive. Then we thought
"Wait a minute, if we can make the MMU transparently map areas like that to the
Falcon registers, we won't have to patch anything at all!"
can i ask why do you find this as easier solution? Patching the binary is a question of one clever script/program which search for 0xffffxxxx in code segment with some exceptions maybe... but it could be automated for sure a lot.
Anyway, hope you didn't all go to sleep! You can check our progress at
http://www.tphf.karoo.net/dbug/falcon.htm. Any comments or criticism is welcome!
I wish you good luck. What rule do you use to choose which game will be ported? I think a lot of games doesn't need to be ported since... they are crap. There is maybe 40-50 cool ST games which are worth to do it...