各位大侠
我用asf建立工程，默认SAMD21-XPRO使用32khz外部时钟 产生48M 主时钟供cpu工作，但是我运行下来发现时钟工作主频1M都不到，
主要时钟设置代码如下
#ifndef CONF_CLOCKS_H_INCLUDED
# define CONF_CLOCKS_H_INCLUDED
/* System clock bus configuration */
# define CONF_CLOCK_FLASH_WAIT_STATES 2
# define CONF_CLOCK_CPU_DIVIDER SYSTEM_MAIN_CLOCK_DIV_1
# define CONF_CLOCK_APBA_DIVIDER SYSTEM_MAIN_CLOCK_DIV_1
# define CONF_CLOCK_APBB_DIVIDER SYSTEM_MAIN_CLOCK_DIV_1
# define CONF_CLOCK_APBC_DIVIDER SYSTEM_MAIN_CLOCK_DIV_1
/* SYSTEM_CLOCK_SOURCE_OSC8M configuration - Internal 8MHz oscillator */
# define CONF_CLOCK_OSC8M_PRESCALER SYSTEM_OSC8M_DIV_1
# define CONF_CLOCK_OSC8M_ON_DEMAND true
# define CONF_CLOCK_OSC8M_RUN_IN_STANDBY false
/* SYSTEM_CLOCK_SOURCE_XOSC configuration - External clock/oscillator */
# define CONF_CLOCK_XOSC_ENABLE false
# define CONF_CLOCK_XOSC_EXTERNAL_CRYSTAL SYSTEM_CLOCK_EXTERNAL_CRYSTAL
# define CONF_CLOCK_XOSC_EXTERNAL_FREQUENCY 12000000UL
# define CONF_CLOCK_XOSC_STARTUP_TIME SYSTEM_XOSC_STARTUP_32768
# define CONF_CLOCK_XOSC_AUTO_GAIN_CONTROL true
# define CONF_CLOCK_XOSC_ON_DEMAND true
# define CONF_CLOCK_XOSC_RUN_IN_STANDBY false
/* SYSTEM_CLOCK_SOURCE_XOSC32K configuration - External 32KHz crystal/clock oscillator */
# define CONF_CLOCK_XOSC32K_ENABLE true
# define CONF_CLOCK_XOSC32K_EXTERNAL_CRYSTAL SYSTEM_CLOCK_EXTERNAL_CRYSTAL
# define CONF_CLOCK_XOSC32K_STARTUP_TIME SYSTEM_XOSC32K_STARTUP_4096
# define CONF_CLOCK_XOSC32K_AUTO_AMPLITUDE_CONTROL false
# define CONF_CLOCK_XOSC32K_ENABLE_1KHZ_OUPUT false
# define CONF_CLOCK_XOSC32K_ENABLE_32KHZ_OUTPUT true
# define CONF_CLOCK_XOSC32K_ON_DEMAND true
# define CONF_CLOCK_XOSC32K_RUN_IN_STANDBY false
/* SYSTEM_CLOCK_SOURCE_OSC32K configuration - Internal 32KHz oscillator */
# define CONF_CLOCK_OSC32K_ENABLE false
# define CONF_CLOCK_OSC32K_STARTUP_TIME SYSTEM_OSC32K_STARTUP_10
# define CONF_CLOCK_OSC32K_ENABLE_1KHZ_OUTPUT true
# define CONF_CLOCK_OSC32K_ENABLE_32KHZ_OUTPUT true
# define CONF_CLOCK_OSC32K_ON_DEMAND true
# define CONF_CLOCK_OSC32K_RUN_IN_STANDBY false
/* SYSTEM_CLOCK_SOURCE_DFLL configuration - Digital Frequency Locked Loop */
# define CONF_CLOCK_DFLL_ENABLE true
# define CONF_CLOCK_DFLL_LOOP_MODE SYSTEM_CLOCK_DFLL_LOOP_MODE_CLOSED
# define CONF_CLOCK_DFLL_ON_DEMAND false
/* DFLL open loop mode configuration */
# define CONF_CLOCK_DFLL_FINE_VALUE (512)
/* DFLL closed loop mode configuration */
# define CONF_CLOCK_DFLL_SOURCE_GCLK_GENERATOR GCLK_GENERATOR_1
# define CONF_CLOCK_DFLL_MULTIPLY_FACTOR 1465//(48000000 / 32768)
# define CONF_CLOCK_DFLL_QUICK_LOCK true
# define CONF_CLOCK_DFLL_TRACK_AFTER_FINE_LOCK true
# define CONF_CLOCK_DFLL_KEEP_LOCK_ON_WAKEUP true
# define CONF_CLOCK_DFLL_ENABLE_CHILL_CYCLE true
# define CONF_CLOCK_DFLL_MAX_COARSE_STEP_SIZE (0x1f / 4)
# define CONF_CLOCK_DFLL_MAX_FINE_STEP_SIZE (0xff / 4)
/* SYSTEM_CLOCK_SOURCE_DPLL configuration - Digital Phase-Locked Loop */
# define CONF_CLOCK_DPLL_ENABLE false
# define CONF_CLOCK_DPLL_ON_DEMAND true
# define CONF_CLOCK_DPLL_RUN_IN_STANDBY false
# define CONF_CLOCK_DPLL_LOCK_BYPASS false
# define CONF_CLOCK_DPLL_WAKE_UP_FAST false
# define CONF_CLOCK_DPLL_LOW_POWER_ENABLE false
# define CONF_CLOCK_DPLL_LOCK_TIME SYSTEM_CLOCK_SOURCE_DPLL_LOCK_TIME_NO_TIMEOUT
# define CONF_CLOCK_DPLL_REFERENCE_CLOCK SYSTEM_CLOCK_SOURCE_DPLL_REFERENCE_CLOCK_REF0
# define CONF_CLOCK_DPLL_FILTER SYSTEM_CLOCK_SOURCE_DPLL_FILTER_DEFAULT
# define CONF_CLOCK_DPLL_REFERENCE_FREQUENCY 32768
# define CONF_CLOCK_DPLL_REFERENCE_DIVIDER 1
# define CONF_CLOCK_DPLL_OUTPUT_FREQUENCY 48000000
/* DPLL GCLK reference configuration */
# define CONF_CLOCK_DPLL_REFERENCE_GCLK_GENERATOR GCLK_GENERATOR_1
/* DPLL GCLK lock timer configuration */
# define CONF_CLOCK_DPLL_LOCK_GCLK_GENERATOR GCLK_GENERATOR_1
/* Set this to true to configure the GCLK when running clocks_init. If set to
* false, none of the GCLK generators will be configured in clocks_init(). */
# define CONF_CLOCK_CONFIGURE_GCLK true
/* Configure GCLK generator 0 (Main Clock) */
# define CONF_CLOCK_GCLK_0_ENABLE true
# define CONF_CLOCK_GCLK_0_RUN_IN_STANDBY false
# define CONF_CLOCK_GCLK_0_CLOCK_SOURCE SYSTEM_CLOCK_SOURCE_DFLL
# define CONF_CLOCK_GCLK_0_PRESCALER 1
# define CONF_CLOCK_GCLK_0_OUTPUT_ENABLE false
/* Configure GCLK generator 1 */
# define CONF_CLOCK_GCLK_1_ENABLE true
# define CONF_CLOCK_GCLK_1_RUN_IN_STANDBY false
# define CONF_CLOCK_GCLK_1_CLOCK_SOURCE SYSTEM_CLOCK_SOURCE_XOSC32K
# define CONF_CLOCK_GCLK_1_PRESCALER 1
# define CONF_CLOCK_GCLK_1_OUTPUT_ENABLE false
。。。
主程序如下
int main (void)
{
system_init();//调用了时钟初始化函数
//configure_tcc();
//configure_tcc_callbacks();
/* Insert application code here, after the board has been initialized. */
configurezero_usart();
configurezero_usart_callbacks();
/*This skeleton code simply sets the LED to the state of the button. */
system_interrupt_enable_global();
uint8_t string[] = "Hello World!\r\n";
usart_write_buffer_wait(&usart_instance, string, sizeof(string));
while (true)
{
// usart_read_buffer_job(&usart_instance, (uint8_t *)rx_buffer, MAX_RX_BUFFER_LENGTH);
port_pin_set_output_level(LED_0_PIN, ledState=!ledState);
double i=0;
for (i=0;i<1000000;i++)
{
}
}
}
请各位大侠指点
|
楼主
标题置顶
标题高亮
