Rabbit 2000, Reference Manual

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52 Rabbit 2000/3000 Microprocessor
Description
Loads the register pair dd (any of the register pairs BC, DE, HL, or SP) with the 16-bit value mn.
Description
•
LD EIR,A:
Loads the External Interrupt Register, EIR, with the data in the Accumulator. The
EIR is used to specify the Most Significant Byte (MSB) of the External Interrupt address. The
value loaded in the EIR is concatenated with the appropriate External Interrupt address to form
the 16-bit ISR starting address.
• LD IIR,A: Loads the Internal Interrupt Register, IIR, with the data in the Accumulator. The
IIR is used to specify the Most Significant Byte (MSB) of the Internal Peripheral Interrupt
address. The value loaded in the IIR is concatenated with the appropriate Internal Peripheral
address to form the 16-bit ISR starting address for that peripheral.
LD dd,mn
Opcode Instruction Clocks Operation
——
01 n m
11 n m
21 n m
31 n m
LD dd,mn
LD BC,mn
LD DE,mn
LD HL,mn
LD SP,mn
6 (2,2,2)
6 (2,2,2)
6 (2,2,2)
6 (2,2,2)
6 (2,2,2)
dd = mn
BC = mn
DE = mn
HL = mn
SP = mn
Flags ALTD I/O
S Z L/V C F R SP S D
- - - - •
LD EIR,A
LD IIR,A
Opcode Instruction Clocks Operation
ED 47 LD EIR,A 4 (2,2) EIR = A
ED 4F LD IIR,A 4 (2,2) IIR = A
Flags ALTD I/O
S Z L/V C F R SP S D
- - - -