clock_masking_example.c

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/* Copyright (c) 2007, Atmel Corporation All rights reserved.
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#include <avr32/io.h>
#include "board.h"
#include "pm.h"
#include "gpio.h"

#define CLOCK_DIV_ON 1
#define CLOCK_DIV_OFF 0
#define DIV_HALF 0
#define DIV_FOURTH 1

int main(void) {
        volatile avr32_pm_t *pm = &AVR32_PM;
        
        // set synchronous clock source to external oscillator 0
        pm_switch_to_osc0(&AVR32_PM, FOSC0, OSC0_STARTUP);
        
        gpio_clr_gpio_pin(LED0_GPIO);
        gpio_clr_gpio_pin(LED1_GPIO);
        
        while(1){
                
                if(gpio_get_pin_value(GPIO_PUSH_BUTTON_0) == 0) {
                        // enable all module clocks on the different clock domains
                        pm->cpumask = 0xFFFFFFFF;
                        pm->hsbmask = 0xFFFFFFFF;
                        pm->pbamask = 0xFFFFFFFF;
                        pm->pbbmask = 0xFFFFFFFF;
                        
                        // Wait for ckrdy bit. Actually not needed here because no write or
                        // read action is performed to any module which clock was disabled
                        // before. 
                        while (!(pm->poscsr & AVR32_PM_POSCSR_CKRDY_MASK));
                        
                        gpio_clr_gpio_pin(LED0_GPIO);
                        gpio_clr_gpio_pin(LED1_GPIO);
                }
                if(gpio_get_pin_value(GPIO_PUSH_BUTTON_1) == 0){
                        // turn off all modules on PBB
                        pm->pbbmask = 0x0;
                        gpio_set_gpio_pin(LED0_GPIO);
                }
                if(gpio_get_pin_value(GPIO_PUSH_BUTTON_2) == 0){
                        // turn off all modules on PBA exept PM/RTC/EIC and GPIO
                        // because we need them to enable the modules again (PM) and to signal
                        // the state withe LEDs
                        pm->pbamask = 0x0000000A;
                        gpio_set_gpio_pin(LED1_GPIO);
                }
                                
        }
        return 0;
}

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