Rabbit 2000 - Altd

Instruction Reference Manual 19
Description
This is an instruction prefix. Causes the instruction immediately following to affect the alternate flags, or use
the alternate registers for the destination of the data, or both. For some instructions ALTD causes special
alternate register uses, unique to that instruction. This instruction is implemented for the Rabbit and is not
available for the Z180
Example
The instruction
ALTD ADD HL,DE
would add the data in word register DE to the data in word register HL and store the result in the alternate
word register HL'.
The instructions
ALTD LD DE,BC
and
LD DE',BC
both load the data in word register BC into the alternate word register DE'.
ALTD
Opcode Instruction Clocks Operation
76 ALTD 2 [Sets alternate register
destination for following
instruction.]
Flags ALTD I/O
S Z L/V C F R SP S D
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