/*------------------------------------------------------------------------
N位压缩BCD加法(C51大端算法代码---乱战修订版)---雁舞白沙出题
此题目的讨论见 https://bbs.21ic.com/club/bbs/ShowAnnounce.asp?id=2464366
修订原因：旧程序在601+999=1600错为1000
是由于ACC = One + Two + 1;编译加了2次，可能是顺序的问题。
才造成了BCD调整错误。
现修改为Two++;ACC = One + Two;
HotPower@126.com 2007.3.14 16:22于西安大雁塔菜地
------------------------------------------------------------------------*/
#include <REGX52.h>
#include "hotins.h"//选自HotPower的《Keil C51红杏出墙记》
/*----------------------------------------------------------------------------
若定义CodeTest则只测试16位BCD加法一种，否则将测试8/16/32/64位的BCD加法
-----------------------------------------------------------------------------*/
#define CodeTest//选择测试16位BCD加法一种
/*----------------------------------------------------------------------------
CodeMode=1:红杏出墙-代码长度130字节 DataAdd()绝对空间53个字节
改天用纯汇编看看有多大的差距
有空和邓苗同志挑战一下纯汇编的~~~
CodeMode=2:利用C51的标志-代码长度154字节 DataAdd()空间比CodeMode1多24个字节
CodeMode=3:正规战-代码长度180字节 DataAdd()空间比CodeMode1多50个字节
注意:不应该测试代码总长度，因为hotins.h要干“坏事”~~~所以应该比较绝对空间大小
-----------------------------------------------------------------------------*/
#define CodeMode 1//选择DataAdd()代码编程模式
/*----------------------------------------------------------------------------
在KeilC51中定义idata数据类型，可能会使代码简洁，因为Keil用了间接寻址.
当然这不利于代码的移植，不过在KeilC51的特定环境下还是很必要的~~~
注意：所长打PP~~~
-----------------------------------------------------------------------------*/
unsigned char idata databuf[24];//64位BCD加法缓冲区
void DataAdd(unsigned char idata *,unsigned char idata *,unsigned char);
void main()
{
_start_();
#ifndef CodeTest
//8位BCD加法(12 + 78 = 90)
(unsigned char)databuf[1] = 0x12;
(unsigned char)databuf[2] = 0x78;
DataAdd(&databuf[1], &databuf[2], 1);//结果在databuf[1]中
//16位BCD加法(1234 + 5678 = 6912)
(unsigned int)databuf[2] = 0x1234;
(unsigned int)databuf[4] = 0x5678;
DataAdd(&databuf[2], &databuf[4], 2);//结果在databuf[0]~databuf[1]中
//24位BCD加法(123456 + 456789 = 580245)
(unsigned char)databuf[3] = 0x12;
(unsigned int) databuf[4] = 0x3456;
(unsigned char)databuf[6] = 0x45;
(unsigned int) databuf[7] = 0x6789;
DataAdd(&databuf[3], &databuf[6], 3);//结果在databuf[0]~databuf[2]中
//32位BCD加法(12345678 + 88888888 = 1 01234566)
(unsigned long)databuf[4] = 0x12345678L;
(unsigned long)databuf[8] = 0x88888888L;
DataAdd(&databuf[4], &databuf[8], 4);//结果在databuf[0]~databuf[3]中
//64位BCD加法(1111111122222222 + 8888888899999999 = 1 0000000022222221)
(unsigned long)databuf[8] = 0x11111111L;
(unsigned long)databuf[12] = 0x22222222L;
(unsigned long)databuf[16] = 0x88888888L;
(unsigned long)databuf[20] = 0x99999999L;
DataAdd(&databuf[8], &databuf[16], 8);//结果在databuf[0]~databuf[7]中
#else
//16位BCD加法(1294 + 4567 = 5861)
(unsigned int)databuf[2] = 0x1294;
(unsigned int)databuf[4] = 0x4567;
DataAdd(&databuf[2], &databuf[4], 2);//结果在databuf[0]~databuf[1]中
//16位BCD加法(1299 + 4567 = 5866)
(unsigned int)databuf[2] = 0x1299;
(unsigned int)databuf[4] = 0x4567;
DataAdd(&databuf[2], &databuf[4], 2);//结果在databuf[0]~databuf[1]中
#endif
while(1)
{
}
}
#if CodeMode == 1 //红杏出墙
void DataAdd(unsigned char idata *DataOneDptr,unsigned char idata *DataTwoDptr,unsigned char DataLend)
{
unsigned char One, Two;//中间变量
unsigned char Sum;//中间变量
F0 = 0;//清除低位向高位的进位
while(DataLend) {//不能DataLend--或--DataLend
DataLend --;//调整到正确的数组位置
One = DataOneDptr[DataLend];//取出正确的被加数
Two = DataTwoDptr[DataLend];//取出正确的加数
if (F0) {//(有上次低位向高位的进位)
//ACC = One + Two + 1;//出错！！！因为加了2次，BCD调整必错，例如601+999=1600错为1000
Two ++;//先+1,肯定自己不会产生AC位
}
ACC = One + Two;//二进制求和(此处可能产生AC位)
_daa_();//BCD码MCS51硬件调整
F0 = CY;//暂存低位向高位的进位
Sum = ACC;//必须定义中间变量,否则ACC直接存不进去databuf[]
databuf[DataLend] = Sum;//只存入低8位
}
}
#else
#if CodeMode == 2 //利用C51的标志
void DataAdd(unsigned char idata *DataOneDptr,unsigned char idata *DataTwoDptr,unsigned char DataLend)
{
unsigned char One, Two;//中间变量
unsigned char Sum;//中间变量
F0 = 0;//清除低位向高位的进位
while(DataLend) {//不能DataLend--或--DataLend
DataLend --;//调整到正确的数组位置
One = DataOneDptr[DataLend];//取出正确的被加数
Two = DataTwoDptr[DataLend];//取出正确的加数
if (F0) {//(有上次低位向高位的进位)
//ACC = One + Two + 1;//出错！！！因为加了2次，BCD调整必错，例如601+999=1600错为1000
Two ++;//先+1,肯定自己不会产生AC位
}
ACC = One + Two;//二进制求和(此处可能产生AC位)
Sum = ACC;//暂存结果
FL = CY;//暂存低位向高位的进位
F0 = 0;//清除低位向高位的进位
if (AC || ((Sum & 0x0f) >= 0x0a)) {//BCD码低4位调整
Sum += 6;//凡加减10或9的都是"混球"~~~
if (CY) FL = 1;//调整后的溢出，例0x94+0x67
}
if (FL || (Sum >= 0xa0)) {//BCD码高4位调整
Sum += 0x60;//注意"混球"~~~
F0 = 1;
}
databuf[DataLend] = Sum;//只存入低8位
}
}
#else //正规战 14:56开始测试
void DataAdd(unsigned char idata *DataOneDptr,unsigned char idata *DataTwoDptr,unsigned char DataLend)
{
unsigned char One, Two, Tmp;//中间变量
unsigned int Sum = 0;//考虑CY位故取整型
while(DataLend) {//不能DataLend--或--DataLend
DataLend --;//调整到正确的数组位置
One = DataOneDptr[DataLend];//取出正确的被加数
Two = DataTwoDptr[DataLend];//取出正确的加数
Sum = One + Two + (Sum >> 8);//二进制求和(注意上次低位向高位的进位)
Tmp = (One & 0xf0) + (Two & 0xf0);//为半进位做准备
if ((Tmp != (Sum & 0xf0)) || ((Sum & 0x0f) > 9)) {//BCD码低4位调整
Sum += 6;//凡加减10或9的都是"混球"~~~
}
if (Sum >= 0xa0) {//BCD码高4位调整
Sum += 0x60;//注意"混球"~~~
}
databuf[DataLend] = Sum;//只存入低8位
}
}
#endif
#endif
相关链接:http://www.**/blog/hotpower/18079/message.aspx |
楼主
标题置顶
标题高亮
