RE: [stella] 6502 question (was INV+ ... )

Subject: RE: [stella] 6502 question (was INV+ ... )
From: "Erik Mooney" <erik@xxxxxxxxxx>
Date: Wed, 7 Apr 2004 09:42:48 -0500
"Thomas Jentzsch" <tjentzsch@xxxxxx> wrote:

> And it wouldn't work anyway, since RTS *reads* from the stack.

Yeah.  Not only would it fail to position the players (since it
doesn't write to RESPx), it would read from the collision
registers, including the undefined lower bits, to use as the
return address for the RTS.  And if the topmost bit of the
collision register is 0, the PC won't even be pointing to ROM.

If anyone can make use of *that*, I'll buy a cartridge and eat it. :)

Thanks to everyone for the help and suggestions on the issue :)
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