Kontron KTAM3874-pITX Manual de usuario descargar pdf (Pagina 62)

KTD-S0057-I Page 58 Linux® Programming Examples (DebianTM)

KTAM3874/pITX Software Guide

/* Set PWM mode */

write_timer_reg (TCLR, (read_timer_reg (TCLR) &

~(TCLR_GPOCFG | TCLR_PT | TCLR_TRG | TCLR_SCPWM)) |

(TCLR_PT | TCLR_TRGOVFLMAT));

return 0;

}

int start_pwm (unsigned long duty_cycle)

{

unsigned long val;

/* Check the duty cycle value */

if ((duty_cycle < 0) || (duty_cycle > DUTY_MAX))

return -1;

/* Set the reload value */

write_timer_reg (TCLR, read_timer_reg (TCLR) | TCLR_AR);

write_timer_reg (TLDR, RELOAD_VAL);

write_timer_reg (TTGR, 0);

/* Set the match value */

write_timer_reg (TCLR, read_timer_reg (TCLR) | TCLR_CE);

val = (FREQ_VAL * duty_cycle) / DUTY_MAX;

write_timer_reg (TMAR, RELOAD_VAL + val);

/* Write the counter value */

write_timer_reg (TCRR, -1);

/* Start the timer */

if (! (read_timer_reg (TCLR) & TCLR_ST))

write_timer_reg (TCLR, read_timer_reg (TCLR) | TCLR_ST);

return 0;

}

int stop_pwm (void)

{

int i;

if (read_timer_reg (TCLR) & TCLR_ST)

{

/* Stop the timer */

write_timer_reg (TCLR, read_timer_reg (TCLR) & ~TCLR_ST);

/* Check if timer off */

for (i = 0; i < STOP_TIMEOUT; i++)

if (! (read_timer_reg (TCLR) & TCLR_ST)) break;

if (i >= STOP_TIMEOUT)

return -1;

}

return 0;

}

1 2 ... 57 58 59 60 61 62 63 64 65 66 67 ... 292 293

Comentarios a estos manuales

Sin comentarios

Kontron KTAM3874-pITX Manual de usuario Pagina 62

Comentarios a estos manuales

Relacionado con productos y manuales para Hardware Kontron KTAM3874-pITX