CC2530 bare metal programming series notes 3--Timer Timer1 free mode program

Timer 1 is a 16-bit timer with timer/counter/pulse width modulation functions. It has 3 individually programmable input capture/output comparison channels, each of which can be used as a PWM output or to capture the edge time of the input signal (for more information on what input capture/output comparison is and how to implement PWM output, readers can refer to the CC2530 Chinese manual). The timer has a very important concept: operating mode. The operating modes include: free-running mode, modulo mode, and up-down mode. The design of the free-mode program for timer Timer1 is as follows:

#include

#define uint unsigned int

#define uchar unsigned char

#define RLED P1_0

#define YLED P1_1

uint counter=0; //Count the number of overflows

uint TempFlag; //Used to mark whether to flash

void Initial(void);

void Delay(uint);

/****************************

//Normal delay program

***************************/

void Delay(uint n)

{

uchar i;

while(n--)

{

for(i=200;i>0;i--);

}

}

/****************************

// Initialization program

***************************/

void Initial(void)

{

// Initialize P1

P1DIR = 0x03; //P10 P11 is output

RLED = 1;

YLED = 1; // Turn off LED

T1CTL = 0x05; //00001101 8-frequency automatic reload

}

/*******************************

//Main function

***************************/

void main(void)

{

static unsigned char cnt = 0;

Initial(); //Call the initialization function

RLED = 0; // Turn on the red LED

while(1) //Query overflow

{

if(IRCON > 0)

{

IRCON = 0; // Clear overflow flag

cnt++;

if(cnt == 15)

{

cnt = 0;

RLED = !RLED;

}

}

}

}

      The main registers used in this program are: T1CTL, IRCON. The value set in the T1CTL register is 0x05. According to the manual, this register configures the frequency division to 8, that is, f/8, and the mode is set to free mode and Free-running. The count value will be counted from 0x0000-0xFFFF. The second bit in IRCON is the interrupt flag bit of timer 1.