Rabbit 2000 - 8.3 Memory Control Unit Registers

96 Rabbit 2000/3000 Microprocessor
Description
A signed multiplication operation is performed on the contents of the 16-bit binary integers contained in the
BC and DE registers. The signed 32-bit result is placed in HL (bits 31 through 16) and BC (bits 15 through 0)
registers.
Examples:
LD BC, 0FFFFh ;BC gets -1
LD DE, 0FFFFh ;DE gets -1
MUL ;HL|BC = 1, HL gets 0000h, BC gets 0001h
In the above example, the 2’s complement of FFFFh is 0001h.
LD BC, 0FFFFh ;BC gets -1
LD DE, 00001h ;DE gets 1
MUL ;HL|BC = -1, HL gets FFFFh, BC gets FFFFh
MUL
Opcode Instruction Clocks Operation
F7 MUL 12 (2,10) HL:BC = BC • DE
Flags ALTD I/O
S Z L/V C F R SP S D
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