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#include "atj213x.h"
static void backlight_set(int level)
{
/* set duty cycle in 1/32 units */
PMU_CHG = ((PMU_CHG & ~PMU_CHG_PDOUT_MASK) | PMU_CHG_PDUT(level));
}
static void wdt_feed(void)
{
RTC_WDCTL |= RTC_WDCTL_CLR;
}
int main(void)
{
int i = 0, j = 0;
/* backlight clock enable, select backlight clock as 32kHz */
CMU_FMCLK = (CMU_FMCLK & ~(CMU_FMCLK_BCLK_MASK)) | CMU_FMCLK_BCKE | CMU_FMCLK_BCLK_32K;
/* baclight enable */
PMU_CTL |= PMU_CTL_BL_EN;
/* pwm output, phase high, some initial duty cycle set as 24/32 */
PMU_CHG = ((PMU_CHG & ~PMU_CHG_PDOUT_MASK)| PMU_CHG_PBLS_PWM | PMU_CHG_PPHS_HIGH | PMU_CHG_PDUT(24));
/* ADEC_N63.BIN seems to setup P_CLK as 7.5MHz which is timer clk */
RTC_T0 = (7500000*10/32); /* with this we should see transition every ~0.3125s and 'black' every ~10s */
RTC_T0CTL = (1<<5) | (1<<2) | (1<<0); /* timer enable, timer reload, clear irq pending bit */
while(1)
{
/* otherwise wdt will trigger reset */
wdt_feed();
/* check if irq pending bit is set */
if (RTC_T0CTL & 1)
{
/* clear irq pending bit */
RTC_T0CTL |= 1;
j++;
backlight_set(j);
}
}
return 0;
}
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