Instruction Set
3-35
RISC 16−Bit CPU
* DADC[.W] Add carry decimally to destination
* DADC.B Add carry decimally to destination
Syntax DADC dst or DADC.W src,dst
DADC.B dst
Operation dst + C −> dst (decimally)
Emulation DADD #0,dst
DADD.B #0,dst
Description The carry bit (C) is added decimally to the destination.
Status Bits N: Set if MSB is 1
Z: Set if dst is 0, reset otherwise
C: Set if destination increments from 9999 to 0000, reset otherwise
Set if destination increments from 99 to 00, reset otherwise
V: Undefined
Mode Bits OSCOFF, CPUOFF, and GIE are not affected.
Example The four-digit decimal number contained in R5 is added to an eight-digit deci-
mal number pointed to by R8.
CLRC ; Reset carry
; next instruction’s start condition is defined
DADD R5,0(R8) ; Add LSDs + C
DADC 2(R8) ; Add carry to MSD
Example The two-digit decimal number contained in R5 is added to a four-digit decimal
number pointed to by R8.
CLRC ; Reset carry
; next instruction’s start condition is defined
DADD.B R5,0(R8) ; Add LSDs + C
DADC 1(R8) ; Add carry to MSDs
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