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

Opcode	Instruction	Operation
--	LD HL,(ps+BC)	L = (ps + BC) H = (ps + BC + 1)
ED 06	LD HL,(PW+BC)	L = (PW + BC) H = (PW + BC + 1)
ED 16	LD HL,(PX+BC)	L = (PX + BC) H = (PX + BC + 1)
ED 26	LD HL,(PY+BC)	L = (PY + BC) H = (PY + BC + 1)
ED 36	LD HL,(PZ+BC)	L = (PZ + BC) H = (PZ + BC + 1)

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	10	n/a	n/a
Rabbit 5000	11	11	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 BC. BC is considered to be sign extended to 24 bits.