今天这个delay是大家常用的东东。我在这里得飘扬一下Atmle.
Atmle是我见到过的所有编译环境里边延时函数最方便的一个啦。
根本就不用自己写啊。况这里是SAMD21，更不用自己写了。我记得ATmega16只是把delay.h包含进来就行。
那么，SAMD21又怎么样呢。
首先，新建一个工程，然后选择开发板，自然选D21啦，然后打开AFS Wizard，把DELAY模块加进来。
然后选择ASF EXPLORER找快带开始指导。没有，这次我本应奇怪但反到高兴了，为什么呢？？？？
没有消息就是好消息！！！！！
连个快速指导都没有说明很简单么？？？？？？
嘿嘿！！！！！！！有个h 文件，打开。
- #ifndef DELAY_H_INCLUDED
- #define DELAY_H_INCLUDED
- #ifdef __cplusplus
- extern "C" {
- #endif
- /**
- * @defgroup group_common_services_delay Busy-Wait Delay Routines
- *
- * This module provides simple loop-based delay routines for those
- * applications requiring a brief wait during execution. Common for
- * API ver. 2.
- *
- * @{
- */
- #ifdef SYSTICK_MODE
- #include "sam0/systick_counter.h"
- #endif
- #ifdef CYCLE_MODE
- #include "sam0/cycle_counter.h"
- #endif
- void delay_init(void);
- /**
- * \def delay_s
- * \brief Delay in at least specified number of seconds.
- * \param delay Delay in seconds
- */
- #define delay_s(delay) cpu_delay_s(delay)
- /**
- * \def delay_ms
- * \brief Delay in at least specified number of milliseconds.
- * \param delay Delay in milliseconds
- */
- #define delay_ms(delay) cpu_delay_ms(delay)
- /**
- * \def delay_us
- * \brief Delay in at least specified number of microseconds.
- * \param delay Delay in microseconds
- */
- #define delay_us(delay) cpu_delay_us(delay)
- #ifdef __cplusplus
- }
- #endif
- /**
- * @}
- */
- #endif /* DELAY_H_INCLUDED */
可见，调用的CORTEX的内核。那谁敢碰啊。
那么我就直接加进初始化那一项
- /*
- * Include header files for all drivers that have been imported from
- * Atmel Software Framework (ASF).
- */
- #include <asf.h>
- int main (void)
- {
- system_init();
-
- delay_init();
- // Insert application code here, after the board has been initialized.
- // This skeleton code simply sets the LED to the state of the button.
- while (1) {
- // Is button pressed?
- //if (port_pin_get_input_level(BUTTON_0_PIN) == BUTTON_0_ACTIVE) {
- // Yes, so turn LED on.
- port_pin_set_output_level(LED_0_PIN, LED_0_ACTIVE);
- delay_ms(1000);
- //} else {
- // No, so turn LED off.
- port_pin_set_output_level(LED_0_PIN, !LED_0_ACTIVE);
- delay_us(1000000);
-
- port_pin_set_output_level(LED_0_PIN, LED_0_ACTIVE);
- delay_s(1);
- //} else {
- // No, so turn LED off.
- port_pin_set_output_level(LED_0_PIN, !LED_0_ACTIVE);
- delay_s(3);
-
- //}
- }
- }
程序是运行一秒LED亮然后一秒LED灭然后又一秒亮，三秒灭。
好今天就到这里，下次是tick就是系统滴答时钟定时。
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楼主
