User’s Manual
25
3.3.4 Register to Register Move
Any of the 8-bit registers, A, B, C, D, E, H, and L, can be moved to any other 8-bit regis-
ter, for example:
LD A,c
LD d,b
LD e,l
The alternate 8-bit registers can be a destination, for example:
LD a',c
LD d',b
These instructions are unique to the Rabbit and require 2 bytes and four clocks because of
the required prefix byte. Instructions such as
LD A,d'
or
LD d',e'
are not allowed.
Several 16-bit register-to-register move instructions are available. Except as noted, these
instructions all require 2 bytes and four clocks. The instructions are listed below.
LD dd',BC ; where dd' is any of HL', DE', BC' (2 bytes, 4 clocks)
LD dd',DE
LD IX,HL
LD IY,HL
LD HL,IY
LD HL,IX
LD SP,HL ; 1-byte, 2 clocks
LD SP,IX
LD SP,IY
Other 16-bit register moves can be constructed by using 2-byte moves.
3.3.5 Register Exchanges
Exchange instructions are very powerful because two (or more) moves are accomplished
with one instruction. The following register exchange instructions are implemented.
EX af,af' ; exchange af with af'
EXX ; exchange HL, DE, BC with HL', DE', BC'
EX DE,HL ; exchange DE and HL
The following instructions are unique to the Rabbit.
EX DE',HL ; 1 byte, 2 clocks
EX DE, HL' ; 2 bytes, 4 clocks
EX DE', HL' ; 2 bytes, 4 clocks
The following special instructions (Rabbit and Z180/Z80) exchange the 16-bit word on
the top of the stack with the HL, the IX, or the IY register. These three instructions are
each 2 bytes and 15 clocks.
EX (SP),HL
EX (SP),IX
EX (SP),IY
Содержание 2000
Страница 1: ...Rabbit 2000 Microprocessor User s Manual 019 0069 041018 M...
Страница 12: ...6 Rabbit 2000 Microprocessor...
Страница 46: ...40 Rabbit 2000 Microprocessor...
Страница 54: ...48 Rabbit 2000 Microprocessor...
Страница 76: ...70 Rabbit 2000 Microprocessor...
Страница 96: ...90 Rabbit 2000 Microprocessor...
Страница 142: ...136 Rabbit 2000 Microprocessor...
Страница 154: ...148 Rabbit 2000 Microprocessor...
Страница 170: ...164 Rabbit 2000 Microprocessor...
Страница 174: ...168 Rabbit 2000 Microprocessor...
Страница 180: ...174 Rabbit 2000 Microprocessor...
Страница 202: ...196 Rabbit 2000 Microprocessor...
Страница 206: ...200 Rabbit 2000 Microprocessor...
Страница 226: ......
Страница 230: ...224 Rabbit 2000 Microprocessor...