输出频率 =238KHz ≈ 24M/100
Duty = 90%/2- 1%=44% 1%为系统预留死区时间
- #include <avr/io.h>
- #define ON_TIME_START_WOA 10
- #define ON_TIME_CYCLES_WOA 90
- #define ON_TIME_START_WOB 10
- #define ON_TIME_CYCLES_WOB 90
- void CLK_Init(void);
- void PORT_Init(void);
- void TCD_Init(void);
- void CLK_Init(void)
- {
- /* Set OSCHF as main clock source */
- _PROTECTED_WRITE(CLKCTRL.MCLKCTRLA, CLKCTRL_CLKSEL_OSCHF_gc);
-
- /* Wait for main clock oscillator changing to finish */
- while (CLKCTRL.MCLKSTATUS & CLKCTRL_SOSC_bm)
- {
- ;
- }
-
- /* Change OSCHF frequency to 24 MHz */
- _PROTECTED_WRITE(CLKCTRL.OSCHFCTRLA, CLKCTRL_FREQSEL_24M_gc);
-
- /* Set the multiplication factor for PLL to 2x */
- _PROTECTED_WRITE(CLKCTRL.PLLCTRLA, CLKCTRL_MULFAC_2x_gc);
- }
- void PORT_Init(void)
- {
- /* Configure PORT A PIN4 and PIN5 as output low */
- PORTA.DIRSET |= PIN4_bm | PIN5_bm;
- PORTA.OUTSET |= PIN4_bm | PIN5_bm;
- }
- void TCD_Init()
- {
-
- /* Select the Two Ramp mode */
- TCD0.CTRLB |= TCD_WGMODE_TWORAMP_gc;
- TCD0.CMPASET = ON_TIME_START_WOA;
- TCD0.CMPACLR = ON_TIME_START_WOA + ON_TIME_CYCLES_WOA;
- TCD0.CMPBSET = ON_TIME_START_WOB;
- TCD0.CMPBCLR = ON_TIME_START_WOB + ON_TIME_CYCLES_WOB;
-
- /* Enable the PWM channels */
- _PROTECTED_WRITE(TCD0.FAULTCTRL, TCD_CMPAEN_bm | TCD_CMPA_bm
- | TCD_CMPBEN_bm | TCD_CMPB_bm);
-
- /* Wait for TCD to be ready for enabling */
- while (!(TCD0.STATUS & TCD_ENRDY_bm))
- {
- ;
- }
-
- /* Select PLL as input clock and enable TCD */
- TCD0.CTRLA |= TCD_CLKSEL_PLL_gc | TCD_ENABLE_bm;
- }
- int main(void)
- {
- CLK_Init();
- PORT_Init();
- TCD_Init();
-
- while (1)
- {
- }
- }
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