Delay_F103.c

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

  Timer2 Setup for Delay in STM32F103C8T6
  Author:   ControllersTech
  Updated:  26th FEB 2021

  ******************************************************************************
  Copyright (C) 2017 ControllersTech.com

  This is a free software under the GNU license, you can redistribute it and/or modify it under the terms
  of the GNU General Public License version 3 as published by the Free Software Foundation.
  This software library is shared with public for educational purposes, without WARRANTY and Author is not liable for any damages caused directly
  or indirectly by this software, read more about this on the GNU General Public License.

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

#include "Delay_F103.h"

uint16_t i;
void TIM2_Config (void)
{
/************** STEPS TO FOLLOW *****************
	1. Enable Timer clock
	2. Set the prescalar and the ARR
	3. Enable the Timer, and wait for the update Flag to set
************************************************/
	
	RCC->APB1ENR |= (1<<0); // enable clock for TIM2 
/*	
	TIM2->CR1 = 0;  				// reset all
	TIM2->CR1 |= (0<<1); 		// UDIS=0; UEV Enabled. The Update event will generate
	TIM2->CR1 |= (0<<4);  	// DIR=1; select UP COUNTER mode
	TIM2->CR1 |= (0<<5);  	// CMS=0;  Edge-aligned mode, up or down count depends on DIR
	TIM2->CR1 |= (0<<8);  	// CKD=0; No clock DIVISION
	TIM2->CR1 |= (0<<7);  	// ARPE=0; ARR Auto Reload Disabled
	TIM2->RCR |= 0;         // Repetition Counter 0
*/	
	TIM2->ARR = 0xffff-1;  	// ARR value
	TIM2->PSC = 72-1;      	// Prescalar value
	
	TIM2->CR1 |= (1<<0);  	// enable timer
	while (!(TIM2->SR & (1<<0)));  // UIF: Update interrupt flag..  This bit is set by hardware when the registers are updated
}

void Delay_us (uint16_t us)
{
	/************** STEPS TO FOLLOW *****************
	1. RESET the Counter
	2. Wait for the Counter to reach the entered value. As each count will take 1 us, 
		 the total waiting time will be the required us delay
	************************************************/
	TIM2->CNT = 0;
	while (TIM2->CNT < us);
}

void Delay_ms (uint16_t ms)
{
	for (i=0; i<ms; i++)
	{
		Delay_us (1000); // delay of 1 ms
	}
}