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serial output problem

Nir boh

hi,
i'm using a- 80c31 microcontroller to send the status
of port bits: p3.3,p3.4,p3.5 using serial comm.
my program works fine only in simulation and i cant
get an idea where is the problem.
i checked the TX pin(11) with a scope and it seems that no data are being sent.

please help...

#include <Reg51.h>
sbit Input1 = 0xB3;     /* P3.3  */
sbit Input2 = 0xB4;     /* P3.4  */
sbit Input3 = 0xB5;     /* P3.5  */

unsigned int Tmr1 = 0;
unsigned int Tmr2 = 0;
unsigned int Tmr3 = 0;

void SendStatus() {
if (Input1 == 0){
        P2 = P2 | 0x03;
        Tmr1 = 0;
        }
if (Input2 == 0){
        P2 = P2 | 0x18;
        Tmr2 = 0;
        }
if (Input3 == 0){
        P2 = P2 | 0xC0;
        Tmr3 = 0;
        }
TI = 0;
SBUF = P2;
while (TI == 0);        /* Wait For Transmit */
if (TF0 == 1) {
        Tmr1 = Tmr1 + 1;
        Tmr2 = Tmr2 + 1;
        Tmr3 = Tmr3 + 1;
        if ((Tmr1>912)&&(Tmr2>912)&&(Tmr3>912)) {
                Tmr1 = 0;
                Tmr2 = 0;
                Tmr3 = 0;
                TR0 = 0;
                TF0 = 0;
                P2 = 0x00;
                }
        else if (Tmr1 == 912) {/* 60 Sec Alarm Hold*/
                P2 = P2 & 0xFC;
                }
        else if (Tmr2 == 912) {/* 60 Sec Alarm Hold*/
                P2 = P2 & 0xE7;
                }
        else if (Tmr3 == 912) {/* 60 Sec Alarm Hold*/
                P2 = P2 & 0x3F;
                }
        else {
                TH0 = 0xFF;
                TL0 = 0xFF;
                TF0 = 0;
                }
        }
}


void main() {

SCON = 0x40; /* 8-bit UART, BaudRate set by Timer-1 */
TMOD = 0x21; /* Timer1 mode 2, Timer-0 mode 1 */
TCON = 0x40; /* Start baud clock */
TR0 = 0;        /* Turn Timer-0 off */
TH0 = 0xFF;
TL0 = 0xFF;
TF0 = 0;        /* Clear rollover flag */
TR0 = 0;        /* Turn timer-0 on */
TH1 = 0xCC;     /* 600 baud 12MHz */
IE = 0x00;      /* Disable serial int */
IP = 0x80;      /* Interrupt priority stopped */
P2 = 0x00;
P3 = 0x00;
Input1 = 1;
Input2 = 1;
Input3 = 1;

while(1) {
  while ((Input1 == 1)&&(Input2 == 1)&&(Input3 == 1)) {
     TI = 0;
     SBUF = 0x00;
     while (TI == 0);/* Wait For Transmit */
     }
     TH0 = 0xFF;
     TL0 = 0xFF;
     TR0 = 1;            /* Turn timer-0 on */
     while (TR0 == 1) SendStatus();
     }
}

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