how to interface ps/2 mouse wih atmel 8051 microcontroller

[user1111]

psclock psdata

also is it possible to communicate ps/2 mouse in serial mode?

 

[Kurenai_ryu]

Re: how to interface ps/2 mouse wih atmel 8051 microcontroll

hi,
about the serial mode. I think its not possible... the ps2 use an extrange 10-11 bit shincronous data packet, where the clock is generated by the mouse!!!

I used RC51 for this routines... hope you find them useful...


----------------------------------------------------
sbit psDATA = P1^0;
sbit psCLOCK = P1^1;


void ps2Inhibit()
{
psDATA = 1;
psCLOCK=0;
}

bit ps2Rb()
{
bit c;
while(psCLOCK);
c=psDATA;
while(!psCLOCK);
return c;
}
char ps2Rx()
{
char i=8,a=0;
psCLOCK=1;
ps2Rb();
do {
a >>= 1;
if (ps2Rb()) a |= 0x80;
} while (--i);

ps2Rb(); //bit: parity...
ps2Rb(); //bit: stop...
return a;
}

void ps2Tb (bit c)
{
while(psCLOCK);
psDATA=c;
while(!psCLOCK);
}

void ps2Tx (char dato)
{
char i=50,pari=0;
psCLOCK=0;
while(--i); //aprox 100us
psDATA=0; //bit: start. (RTS)
i=8;
psCLOCK=1; // RTS...
do {
if (dato & 1) {ps2Tb(1); pari++;}
else ps2Tb(0);
dato >>=1;
} while(--i);

(pari & 1)? ps2Tb(0) : ps2Tb(1); //bit par
ps2Tb(1);
while(psCLOCK);
while(!psCLOCK);
}

char Tipo;
signed char mouse_X=0;
signed char mouse_Y=0;
signed char mouse_Z=0;

void init_MOUSE()
{
ps2Tx(0xFF); //reset
ps2Rx(); //Acknoledge
ps2Rx(); //self Test = AAh
ps2Rx(); //mouse ID = 00h
ps2Tx(0xF3); //sampling...
ps2Rx(); //-Acknoledge
ps2Tx(0xC8); // 200
ps2Rx(); // Acknoledge

ps2Tx(0xF3); //sampling...
ps2Rx(); // Acknoledge
ps2Tx(0x64); // 100
ps2Rx(); // Acknoledge

ps2Tx(0xF3); //sampling...
ps2Rx(); //Acknoledge
ps2Tx(0x50); //80
ps2Rx(); //Acknoledge

ps2Tx(0xF2); //ID
ps2Rx(); //Acknoledge
Tipo = ps2Rx(); //mouse ID =00 normal 03 intelli

ps2Tx(0xF3); //final sampling...
ps2Rx(); // Acknoledge
ps2Tx(0x0A); // 10 (je je je I'm slow...)
ps2Rx(); // Acknoledge

ps2Tx(0xE8); //Res...
ps2Rx(); // Acknoledge
ps2Tx(0x00); //1 count/mm
ps2Rx(); // Acknoledge

}

char mouse_STAT;
signed char mouse_dX;
signed char mouse_dY;
signed char mouse_dZ;

void read_mouse ()
{
ps2Tx(0xEB); // Data
ps2Rx(); // Acknoledge
mouse_STAT=ps2Rx();
mouse_dX = ps2Rx();
mouse_dY = ps2Rx();
if (Tipo) mouse_dZ = ps2Rx();
//abosolute pos...
mouse_X +=mouse_dX;
mouse_Y +=mouse_dY;
if (Tipo) mouse_Z +=mouse_dX;
}

---------------------------------------------------


now first you should call

init_MOUSE();

then

read_mouse();

to read values in mouse_X, mouse_Y And maybe mouse_Z (also the mouse_dX, and so.. are useful...)

hope you already searched for the PS/2 format and the PS/2 mouse commands...


cheers!