题目内容

可编程序控制器的输入／输出响应速度受( )影响较大。A、器件性能 B、扫描周期 C、程序 D、外接设备

A. 器件性能
B. 扫描周期
C. 程序
D. 外接设备

查看答案

搜索结果不匹配？点我反馈

更多问题

选出适合Allen和Sara的匹配字母。A. eat more vegetables and fruitsB. go outside with classmatesC. do some exerciseD. eat regular mealsE. eat a balanced dietF. drink less than 2 cups of coffee every dayFor Allen（1）For Sara （2）

木地板的铺设方式有和两种。

一般楼地板由和组成。

以下代码实现了Time1中断。1）试参考这些代码，改Time1中断为PWM2中断，控制LED灯闪亮及蜂鸣器声响（实验成功后记录现象说明修改方法）？2)试解读这些代码的功能，假设定时器时钟源PCLK频率为150MHz，试修改代码使蜂鸣器不断发出1秒响停3秒的声音？#include "s5p6818.h"extern void printf (const char *fmt, ...);void led_d7_toggle(void);void do_irq(void){ unsigned int num_irq;static unsigned int irq_cnt=0;// 获取中断号num_irq = GICC_IAR & (0x3FF << 0);switch(num_irq){case 56:{GICD_ICPENDER.ICPENDER1 = GICD_ICPENDER.ICPENDER1 | (0x1 << 24);irq_cnt++;printf("timer irq %d\r\n",irq_cnt);//led灯闪烁led_d7_toggle();//清空定时器1中断标志位TIMER.TINT_CSTAT |=(1<<6);}break;default:break;}// 清除所有中断GICC_EOIR = GICC_EOIR & (~(0x3FF << 0)) | num_irq;}//全局中断控制分配初始化void gic_dist_init(void){//GIC监测外设中断并将挂起中断转达到CPU接口的控制位，为0即关闭GICD_CTRL = 0x0;//具体的中断使能控制位，占1比特。为1即打开GICD_ISENABLER.ISENABLER1 = GICD_ISENABLER.ISENABLER1 | (0x1 << 24);//具体的中断优先级控制位，占8比特。数值小优先级高。GICD_IPRIORITYR.IPRIORITYR14 = GICD_IPRIORITYR.IPRIORITYR14 & (~(0xFF << 0)) | (56 << 0);//具体的中断目标分配控制位，占8比特。为1即选中该CPUGICD_ITARGETSR.ITARGETSR14 = GICD_ITARGETSR.ITARGETSR14 & (~(0xFF << 0)) | (0x1 << 0);//具体的中断模式控制位，占2比特GICD_ICFGR.ICFGR3 = GICD_ICFGR.ICFGR3 & (~(0x3 << 16));//打开分配器总开关GICD_CTRL = 0x1;}void gic_cpu_init(void){GICC_PMR = 0xf0;GICC_CTRL = 0x1;}void s5p6818_irq_init(void){gic_dist_init();gic_cpu_init();}void Timer_init(void){// Timer1,作定时器中断// 2. 设置一级预分频值为249(250分频)TIMER.TCFG0 = (TIMER.TCFG0 & (~(0xFF << 0))) | (249 << 0);// 3. 设置二级与分频值，进行16分频TIMER.TCFG1 = (TIMER.TCFG1 & (~(0xF << 4))) | (0x4 << 4);// 4. 设置TIMER1的最终周期;TIMER.TCNTB1 = 37500;// 6. 打开手动加载TIMER.TCON = TIMER.TCON | (0x1 << 9);// 7. 关闭手动加载TIMER.TCON = TIMER.TCON & (~(0x1 << 9));// 8. 打开自动加载TIMER.TCON = TIMER.TCON | ((0x1 << 11));TIMER.TINT_CSTAT |=(1<<6)|(1<<1);// 9. 使能TIMER定时器TIMER.TCON = TIMER.TCON | ((0x1 << 8));}void led_d7_toggle(void){GPIOB.OUT = GPIOB.OUT ^ (0x1<<26);}void Led_Init(void){// 1. 设置引脚功能为GPIO功能，查看芯片手册2.3.1章节GPIOB.ALTFN1 = GPIOB.ALTFN1 & (~(0x3 << 20));GPIOB.ALTFN1 = GPIOB.ALTFN1 | (0x1 << 20);// 2. 设置引脚为输出功能GPIOB.OUTENB = GPIOB.OUTENB | (0x1 << 26);GPIOB.OUT = GPIOB.OUT & (~(0x1 << 26));}int main(void){printf("Hello Teacher.He\r\n");printf("This is timer irq test\r\n");Led_Init();s5p6818_irq_init();Timer_init();while(1){}return 0;}