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LD A,EIR
LD A,IIR     Load     Rabbit 2000/3000/4000/5000 Instruction

Opcode	Instruction	Operation
ED 57	LD A,EIR	A = EIR
ED 5F	LD A,IIR	A = IIR

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 2000/3000/4000	4	n/a	n/a
Rabbit 5000	4	4	2

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

Description

Loads A with EIR or IIR.

EIR is used to specify the most significant byte of the External Interrupt address. The value loaded in EIR is concatenated with the appropriate External Interrupt address to form the 16-bit ISR starting address. IIR is used to specify the most significant byte of the Internal Peripheral Interrupt address. The value loaded in IIR is concatenated with the appropriate Internal Peripheral address to form the 16-bit ISR starting address for that peripheral.