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LD (pd+d),BCDE     Load     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
--	LD (pd+d),BCDE	(pd+d) = E; (pd+d+1) = D (pd+d+2) = C; (pd+d+3) = B
DD 0F d	LD (PW+d),BCDE	((PW+d) = E; (PW+d+1) = D (PW+d+2) = C; (PW+d+3) = B
DD 1F d	LD (PX+d),BCDE	((PX+d) = E; (PX+d+1) = D (PX+d+2) = C; (PX+d+3) = B
DD 2F d	LD (PY+d),BCDE	((PY+d) = E; (PY+d+1) = D (PY+d+2) = C; (PY+d+3) = B
DD 3F d	LD (PZ+d),BCDE	((PZ+d) = E; (PZ+d+1) = D (PZ+d+2) = C; (PZ+d+3) = B

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	19	n/a	n/a
Rabbit 5000	20	19	18

Flags				ALTD			IOI/IOE
S	Z	L/V	C	F	R	SP	S	D
-	-	-	-

Description

Loads the memory location whose address is computed as the sum of pd and the 8-bit signed displacement d with BCDE.

The address is treated either as a logical address that will be passed through the MMU for translation into a physical address or as a physical address that does not need MMU translation.

If pd is 0xFFFFxxxx, i.e., the upper 16 bits are all ones, it represents a logical address. This is called a "long logical" address. Otherwise, it is a physical address with the low 20 bits or 24 bits being significant (depending on the memory available).