[Coco] CoCo 3 MMU test for all
jdaggett at gate.net
jdaggett at gate.net
Mon Jan 21 21:13:18 EST 2008
On 21 Jan 2008 at 20:01, Roger Taylor wrote:
> CCASM also uses 5 bit offsets whenever possible where I think EDTASM
> uses 8 bits or even larger sometimes for forward references, but it's
> been a while since I dug deep into these matters and I'm a bit foggy
> on *all* of the details. Major information overload. :)
correct. any offset that is zero whether 0,X or ,X for indexing should
genereate a two byte operation. the first being the ld opcode and the second
byte fetched is the post byte opcode. 8 and 16 bit offsets require more bytes
loaded and more machine cycles. 8 bit offsets require another byte to be
loaded and a 16 bit offset requires another 2 bytes to be loaded.
james
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