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Mode 13 bits Counter Software Gated (not used)

/*********
* Copyright (c) 2004 Atmel.
* @brief This file is an example to use timer0 in mode 0.
* Put here the functional description of this file within the software
* architecture of your program.
*
**********/
/* @section I N C L U D E S */
#include "reg_c51.h"
/***********
* FUNCTION_PURPOSE: This file set up timer 0 in mode 0 (13 bits counter)
* with a software gate. The counter count up at each negative transition.
* The 13-bits register consist of all 8 bits of TH0 and the lower 5 bits
* of TL0. The upper 3 bits of TL0 are undeterminate and are ignored.
* FUNCTION_INPUTS: P3.4(T0) must be controlled by an external clock
* FUNCTION_OUTPUTS: void
**********/
void main(void)
{
  TMOD &= 0xF0;/* Timer 0 mode 0 counter with software gate */
  TMOD |= 0x04;/* GATE0=0; C/T0#=1; M10=0; M00=0; */
  TH0 = 0x00; /* init values */
  TL0 = 0x00;
  ET0=1; /* enable timer0 interrupt */
  EA=1; /* enable interrupts */
  TR0=1; /* timer0 run */
  while(1); /* endless */
}
/*****
* FUNCTION_PURPOSE: timer0 interrupt
* FUNCTION_INPUTS: void
* FUNCTION_OUTPUTS: P1.0 toggle period = 2 * 8192 * P3.4(T0) period
*****/
void it_timer0(void) interrupt 1 /* interrupt address is 0x000b */
{
  TF0 = 0; /* reset interrupt flag (already done by hardware)*/
  P1_0 = ~P1_0;/* P1.0 toggle when interrupt. */
}
Mode 13 bits Counter Hardware Gated

/****
* Copyright (c) 2004 Atmel.
* @brief This file is an example to use timer0 in mode 0.
* Put here the functional description of this file within the software
* architecture of your program.
****/
/* @section I N C L U D E S */
#include "8051.h"
/****
* FUNCTION_PURPOSE: This file set up timer 0 in mode 0 (13 bits counter)
* with a hardware gate. The counter count up at each negative transition.
* The 13-bits register consist of all 8 bits of TH0 and the lower 5 bits
* of TL0. The upper 3 bits of TL0 are undeterminate and are ignored.
* FUNCTION_INPUTS: P3.2(INT0)=1 : GATE Input
* P3.4(T0) controlled by an external clock
* FUNCTION_OUTPUTS: void
****/
void main(void)
{
  TMOD &= 0xF0;/* Timer 0 mode 0 counter with hardware gate */
  TMOD |= 0x0C;/* GATE0=1; C/T0#=1; M10=0; M00=0; */
  TH0 = 0x00; /* init values */
  TL0 = 0x00;
  ET0=1; /* enable timer0 interrupt */
  EA=1; /* enable interrupts */
  TR0=1; /* timer0 run */
  while(1); /* endless */
}

/****
* FUNCTION_PURPOSE: timer0 interrupt
* FUNCTION_INPUTS: void
* FUNCTION_OUTPUTS: P1.0 toggle period = 2 * 8192 * P3.4(T0) period
***/
void it_timer0(void) interrupt 1 /* interrupt address is 0x000b */
{
TF0 = 0; /* reset interrupt flag (already done by hardware)*/
P1_0 = ~P1_0;/* P1.0 toggle when interrupt. */
}

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Programmer
ISP 89s

Free Software
a. Edsim 51
b. MIDE-51
c. ATMEL ISP

Lesson 1:
Architecture
1.1.Memory
1.2.SFR
1.3.Addressing
1.4.Instruction Set
1.5.Assignment

Lesson 2:
Input Output
2.1.LED
2.2.Swicht
2.3.7 Segmen
2.4.LCD Character
2.5.ADC
2.6.DAC
2.7.Motor Stepper
2.8.Keypad
2.9.Assignment

Lesson 3:
Timer Counter
3.1.Basic
3.2.Mode 0
3.3.Mode 1
3.4.Mode 2
3.5.Mode 3
3.5.Assignment

Lesson 4:
Serial Comm.
4.1.Basic
4.2.LED
4.3.Rotate LED
4.2 ADC
4.3.LCD
4.4.Assignment

Lesson 5:
Interuption
5.1.Basic
5.2.Timer
5.2.External
5.3.Assignment