C51模拟PS2键盘（四）
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C51模拟PS2键盘程序，这是PS2协议程序头文件文件：
#ifndef __PS_2_H__ #define __PS_2_H__ #define PS2_DAT_H 1 #define PS2_DAT_L 0 #define PS2_CLK_H 1 #define PS2_CLK_L 0 sbit PS2_CLK = P0^0; sbit PS2_DAT = P0^1; void PS2_Send(unsigned char ch); unsigned char PS2_Rece(void); unsigned char PS2_Response(void); void MCU_To_PC(unsigned char Key_num); //void key_send(unsigned char key_value); //unsigned int key_scan(void); #endif
#include <C8051F310.h> // SFR declarations
#include "PS_2.h"
#include "delay.h"
#include "Initialize.h"
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
//
// Return Value : None
// Parameters :
//
// This function
//
//
//
//-----------------------------------------------------------------------------
void PS2_Send(unsigned char ch)
{
unsigned char i,temp,char_temp;
unsigned char odd_flag=1; //if odd_flag is 1,then odd is true ,else is flase
temp=ch;
for(i=0;i<8;i++) //find the number of 1 in this uchar x iS odd or not
{
char_temp=temp&0x01; //奇效验，找出发送的数据中1的个数，如果为偶数，则置标志位为1，反之为0
if(char_temp==0x01)
{
odd_flag=!odd_flag;
}
temp=temp>>1;
}
temp=ch;
char_temp=0;
while(!PS2_CLK)
{
Delay_us(20);
}
PS2_DAT = PS2_DAT_L; //start bit 0
Delay_us(18); //从时钟脉冲的上升沿到一个数据转变的时间至少要有5微秒
PS2_CLK = PS2_CLK_L;
Delay_us(35);
for(i=0;i<8;i++) //send 8 bits LSB first
{
PS2_CLK = PS2_CLK_H;
Delay_us(13); //从时钟脉冲的上升沿到一个数据转变的时间至少要有5微秒
char_temp=temp&0x01;
if(char_temp==0x01)
PS2_DAT = PS2_DAT_H;
else
PS2_DAT = PS2_DAT_L;
char_temp = 0;
Delay_us(22);
PS2_CLK = PS2_CLK_L;
Delay_us(36);
temp=temp>>1;
}
PS2_CLK = PS2_CLK_H;
Delay_us(13); //从时钟脉冲的上升沿到一个数据转变的时间至少要有5微秒
PS2_DAT = odd_flag; //send odd bit
Delay_us(22);
PS2_CLK = PS2_CLK_L;
Delay_us(36);
PS2_CLK = PS2_CLK_H; //send stop bit
Delay_us(13); //从时钟脉冲的上升沿到一个数据转变的时间至少要有5微秒
PS2_DAT = PS2_DAT_H;
Delay_us(22);
PS2_CLK = PS2_CLK_L;
Delay_us(36);
PS2_CLK = PS2_CLK_H;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
//
// Return Value :
// Parameters :
//
// This function
//
//
//
//-----------------------------------------------------------------------------
unsigned char PS2_Rece(void)
{
unsigned char i,dat=0x00;
unsigned char ParityBit,oddSum=0; //数据校验计数器
if(!PS2_DAT)
{
Delay_us(10);
if(PS2_DAT) return 0xCC;
while(!PS2_CLK);
Delay_us(40);
PS2_CLK = PS2_CLK_L;
for(i=0;i<8;i++) //read 8bit
{
Delay_us(35);
PS2_CLK = PS2_CLK_H;
Delay_us(36);
PS2_CLK = PS2_CLK_L;
dat=dat>>1;
if(PS2_DAT)
{
dat|=0x80;
oddSum++; //校验位计数器
}
Delay_us(15);
}
Delay_us(35);
PS2_CLK = PS2_CLK_H;
Delay_us(36);
PS2_CLK = PS2_CLK_L;
if(PS2_DAT)
ParityBit=1; //奇偶效验
else
ParityBit=0;
Delay_us(35);
PS2_CLK = PS2_CLK_H;
Delay_us(36);
PS2_CLK = PS2_CLK_L;
if(!PS2_DAT) //数据线仍旧为0吗
return 0xCC;
Delay_us(15);
PS2_DAT = PS2_DAT_L;
Delay_us(20);
PS2_CLK = PS2_CLK_L; //STOP BIT H_DATA 0 ERR
Delay_us(36);
PS2_CLK = PS2_CLK_H; //ACK bit
Delay_us(15);
PS2_DAT = PS2_DAT_H;
oddSum += ParityBit; //数据位中1的个数加上校验为应为奇数
if(oddSum%2==0)
return 0xCC;
else
return dat;
}
else
return 0xCC;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
//
// Return Value :
// Parameters :
//
// This function
//
//
//
//-----------------------------------------------------------------------------
unsigned char PS2_Response(void) //开机应答,使电脑能识别到键盘
{
unsigned char PS2RecChar;
//while(PS2RecChar != 0xFF)
PS2RecChar = PS2_Rece();
if(PS2RecChar != 0xCC)
switch(PS2RecChar)
{
Delay_ms(4);
case 0xFF: //主机命令设备复位(0xff),设备必须应答0xfa后回复0xaa;
PS2_Send(0xFA);
Delay_ms(3);
PS2_Send(0xAA);
break;
case 0xF2: // 主机请求获得设备ID命令(0xf2),设备必须应答0xfa后回复0xab,0x83;
PS2_Send(0xFA);
Delay_ms(3);
PS2_Send(0xAB);
Delay_ms(3);
PS2_Send(0x83);
// LED = 1;
break;
case 0xEE: //主机ECHO命令(0xee)，设备直接回复0xee;
PS2_Send(0xEE);
break;
case 0xEF:
PS2_Send(0xFA);
Delay_ms(3);
PS2_Send(0xBF);
Delay_ms(3);
PS2_Send(0xB0);
break;
//除以上命令之外的其它命令，设备只要回复0xfa即可，当然要视设备的功能作相应的动作。
/*case 0xF5:
PS2_Send(0xFA);
break;*/
case 0xF3:
PS2_Send(0xFA);
break;
case 0x00:
PS2_Send(0xFA);
break;
case 0x02:
PS2_Send(0xFA);
break;
case 0x20:
PS2_Send(0xFA);
break;
case 0xED:
PS2_Send(0xFA);
break;
case 0xF0:
PS2_Send(0xFA);
break;
case 0xEC:
PS2_Send(0xFE);
break;
case 0xFE:
PS2_Send(0xFA);
break;
case 0xF1:
PS2_Send(0xFA);
break;
case 0xF4:
PS2_Send(0xFA);
break;
case 0xAA:
PS2_Send(0xAA);
break;
default :break;
}
Delay_ms(4);
return PS2RecChar;
}
//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------
//
// Return Value :
// Parameters :
//
// This function
//
//
//
//-----------------------------------------------------------------------------
/*
void MCU_To_PC(unsigned char Key_num)
{
switch(Key_num)
{
case 1: //'f'
PS2_Send(0x2B);
Delay_ms(60);
break;
case 2: //L ARROW
PS2_Send(0xE0);
Delay_ms(4);
PS2_Send(0x6B);
Delay_ms(60);
break;
case 3: //'Enter'
PS2_Send(0x5A);
Delay_ms(60);
break;
default:
break;
}
}
*/
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C51模拟PS2键盘（三）：原文链接
程序包的位置在这里
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