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LD HL,(ps+d)     Load     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
--	LD HL,(ps+d)	L = (ps + d) H = (ps + d + 1)
85 d	LD HL,(PW+d)	L = (PW + d) H = (PW + d + 1)
95 d	LD HL,(PX+d)	L = (PX + d) H = (PX + d + 1)
A5 d	LD HL,(PY+d)	L = (PY + d) H = (PY + d + 1)
B5 d	LD HL,(PZ+d)	L = (PZ + d) H = (PZ + d + 1)

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	9	n/a	n/a
Rabbit 5000	10	10	9

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

Description

Loads HL with the data whose 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 ps 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).

The address is computed as the sum of ps and the 8-bit signed displacement d.