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

Opcode	Instruction	Operation
--	LD A,(ps+HL)	A = (ps + HL)
8B	LD A,(PW+HL)	A = (PW + HL)
9B	LD A,(PX+HL)	A = (PX + HL)
AB	LD A,(PY+HL)	A = (PY + HL)
BB	LD A,(PZ+HL)	A = (PZ + HL)

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	6	n/a	n/a
Rabbit 5000	7	7	7

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

Description

Load A 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, with only the low 16 bits being significant. This is called a "long logical" address. Otherwise, it is a physical address with the low 20 or 24 bits (depending on the memory that is used) being significant.

The address is computed as the sum of ps and HL. HL is considered to be sign extended to 24 bits.