PersonalVotingMachine/basic-setup/components/u8g2/sys/arm/lpc804/ctimer/main.c

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2020-12-22 14:30:09 +02:00
/*
use ctimer to do a LED blink
*/
#include <LPC8xx.h>
#include <iocon.h>
#include <syscon.h>
#include <gpio.h>
#include <swm.h>
#include <ctimer.h>
#include <delay.h>
/*=======================================================================*/
/* Configuration */
#define SYS_TICK_PERIOD_IN_MS 100
/*=======================================================================*/
/* system procedures and sys tick master task */
volatile uint32_t sys_tick_irq_cnt=0;
void __attribute__ ((interrupt)) SysTick_Handler(void)
{
sys_tick_irq_cnt++;
}
/*=======================================================================*/
/*
replacement for ConfigSWM(uint32_t func, uint32_t port_pin)
Args:
fn: A function number, e.g. T0_MAT0, see swm.h
port: A port number for the GPIO port (0..30)
*/
void mapFunctionToPort(uint32_t fn, uint32_t port)
{
/* first reset the pin assignment to 0xff (this is also the reset value */
LPC_SWM->PINASSIGN[fn/4] |= ((0xffUL)<<(8*(fn%4)));
/* then write the destination pin to it */
LPC_SWM->PINASSIGN[fn/4] &= ~((port^255UL)<<(8*(fn%4)));
}
/*=======================================================================*/
/*
setup the hardware and start interrupts.
called by "Reset_Handler"
*/
int __attribute__ ((noinline)) main(void)
{
/* call to the lpc lib setup procedure. This will set the IRC as clk src and main clk to 24 MHz */
SystemInit();
/* if the clock or PLL has been changed, also update the global variable SystemCoreClock */
SystemCoreClockUpdate();
/* set systick and start systick interrupt */
SysTick_Config(main_clk/1000UL*(unsigned long)SYS_TICK_PERIOD_IN_MS);
/* init GPIOs */
GPIOInit();
/* enable clock for several subsystems */
Enable_Periph_Clock(CLK_IOCON);
Enable_Periph_Clock(CLK_SWM);
Enable_Periph_Clock(CLK_CTIMER0);
GPIOSetDir( PORT0, 15, OUTPUT);
LPC_CTIMER0->PR = 0; /* no prescale */
LPC_CTIMER0->MR[3] = 15000000; /* PWM cycle length: one second with 15MHz AHB clock */
LPC_CTIMER0->MCR |= 1<<MR3R; /* Use MR3 value to reset the counter: MR3 is the upper value and sets the PWM cycle */
LPC_CTIMER0->MR[0] = 14000000; /* PWM duty cycle in MR0 */
LPC_CTIMER0->PWMC |= 1<<PWMEN0; /* PWM mode for MR0 */
/* invert output, will only work with PIO0_30, not with PIO0_15 */
LPC_IOCON->PIO0_30 |= 1<<IOCON_INV;
/* connect subsystems to the GPIOs */
/* Just for testing: The signal is routed via PIN0_30 */
mapFunctionToPort(T0_MAT0, 30);
mapFunctionToPort(LVLSHFT_IN0, 30);
mapFunctionToPort(LVLSHFT_OUT0, 15);
/* enable the timer */
LPC_CTIMER0->TCR |= 1<<CEN;
}