标题: PIC单片机无符号BCD加法子程序 [打印本页] 作者: liyf 时间: 2012-1-27 18:22 标题: PIC单片机无符号BCD加法子程序 ;******************* 无符号 BCD 加法 ***************;; This routine performs a 2 Digit Unsigned BCD Addition; It is assumed that the two BCD numbers to be added are in; locations Num_1 & Num_2. The result is the sum of Num_1+Num_2; and is stored in location Num_2 and the overflow carry is returned; in location Num_1;; Performance :; Program Memory : 25; Clock Cycles : 17 ( worst case );;*******************************************************************;;Num_1 equ 8 ; 加数寄存器，加法和的高位寄存器。result equ 8;Num_2 equ 9 ; 加数寄存器，加法和的低位寄存器。O_flow equ 9; 其它的寄存器自己定义 ;BCDAdd movf Num_1,Wclrf Num_1 ;clear num_1addwf Num_2,1 ; do binary additionbtfsc STATUS,C ; max number );self goto self ；如不是测试程序，这句无用;;org 1FFgoto main;END