embedded c program, 12MHz crystal, 1ms time delay, generating time delay

Writing an Embedded C Program to Generate 1ms Time Delay by Using 12MHz Frequency

To generate a 1ms time delay using a 1ms delay frequency and a 12MHz clock in Embedded C, you can use a timer module in the microcontroller. Here's an example code that demonstrates how to generate a 1ms delay using Timer 0 of an 8051 microcontroller:

Steps:

1. Include the necessary header files.
2. Set the frequency value to 12MHz.
3. Calculate the amount of clock cycles needed to generate the desired time delay.
4. Create a loop that runs for the total amount of clock cycles.
5. Within the loop, use the delay function to wait for a fixed interval of time.

The following is an example of the code required to generate a 1ms time delay using an embedded c programming language and a 12MHz frequency.

#include <reg52.h>

// Function to initialize Timer 0
void init_timer0(void)
{
    TMOD |= 0x01;   // Set Timer 0 in mode 1 (16-bit timer)
    TH0 = 0xFC;     // Set initial value of high byte for 1ms delay at 12MHz
    TL0 = 0x18;     // Set initial value of low byte for 1ms delay at 12MHz
    TR0 = 1;        // Start Timer 0
}

// Function to generate 1ms delay using Timer 0
void delay_ms(unsigned int time_ms)
{
    unsigned int i, j;
    for(i = 0; i < time_ms; i++)
    {
        for(j = 0; j < 125; j++) // Loop to generate 1ms delay at 12MHz
        {
            while(!TF0);    // Wait until Timer 0 overflows
            TF0 = 0;        // Reset Timer 0 overflow flag
        }
    }
}

// Main function
void main()
{
    init_timer0();  // Initialize Timer 0
    while(1)
    {
        // Generate a 1ms delay and toggle an LED
        P1 ^= 0x01;     // Toggle LED connected to P1.0
        delay_ms(1000); // Generate a 1s delay
    }
}

In the code above, the init_timer0() function initializes Timer 0 with the values for a 1ms delay at 12MHz, and starts the timer. The delay_ms() function uses a nested loop to generate a delay of the specified number of milliseconds by waiting for Timer 0 to overflow. The main function toggles an LED connected to P1.0 every 1 second using the delay_ms() function.

Note that the specific values for TH0 and TL0 used in the init_timer0() function may vary depending on the exact microcontroller being used and the desired delay frequency.