最近在使用NER24L01无线模块，弄了很久，几块最小系统板都用不了，只有其中一块板可以用。无线模块在别人那里测试过是没问题的，估计是51单片机的电平难以和无线模块兼容。请问有什么3.3V、5V双向转换的芯片，因为要实现模块与单片机之间的数据传输
2012-08-24 17:14
有哪一位能推荐学习PCB的好书吗？谢谢。
2016-09-25 11:16
是否有人能如此好地解释你的点击，以便保留你在重新生成时对MCC生成的文件所做的更改？我刚刚丢失了一天的工作，因为我又搞错了。我找不到能显示当前界面和做什么的文档。我看到顶部有一个左到右箭头，它似乎用MCC’替换了你的所有工作。这是你工作的一个段落，还有一个小红十字会，你可以直接删除你的工作。一切似乎都会导致“丢掉你的工作”。？？？完全糊涂 以上来自于百度翻译 以下为原文 Would anyone be be so good as to explain with a screenshot where you click in order to retain the changes that you have made to MCC generated files during re-generation? I've just lost a day's work because I got it wrong AGAIN. There's no documentation I can find that shows the current interface and what to do. I see a left to right arrow at the top which seems to replace all your work with MCC's. A left to right arrow at the level of the latest MCC change which replaces an individual paragraph of your work. And a little red cross where you can delete your work directly. Everything seems to lead to "losing your work"??? Utterly confused.
2019-04-22 15:04
我最近在写四轴飞行器 我的程序 启动4个电机后 程序就死了 完全不动需要重启 别人的程序 启动电机没问题 同样的板子(都是改变PWM 占空比) 这事什么问题嘞 void Motor_Init(void ){ GPIO_InitTypeDef GPIO_InitStructure;//IO口配置参数 TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;//定时器配置参数 TIM_OCInitTypeDef TIM_OCInitStructure;// //使能时钟 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE); //RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO,ENABLE); //设置电机使用到得管脚 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 ;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_Init(GPIOA, &GPIO_InitStructure); TIM_TimeBaseInitStructure.TIM_Period = eriod_Max; TIM_TimeBaseInitStructure.TIM_Prescaler = 2; TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1; TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM2,&TIM_TimeBaseInitStructure); TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 0; TIM_OC1Init(TIM2,&TIM_OCInitStructure); TIM_OC1PreloadConfig(TIM2,TIM_OCPreload_Enable); TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 0; TIM_OC2Init(TIM2,&TIM_OCInitStructure); TIM_OC2PreloadConfig(TIM2,TIM_OCPreload_Enable); TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 0; TIM_OC3Init(TIM2,&TIM_OCInitStructure); TIM_OC3PreloadConfig(TIM2,TIM_OCPreload_Enable); TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = 0; TIM_OC4Init(TIM2,&TIM_OCInitStructure); TIM_OC4PreloadConfig(TIM2,TIM_OCPreload_Enable); TIM_ARRPreloadConfig(TIM2, ENABLE); TIM_Cmd(TIM2,ENABLE); } void Motor_Working(uint16_t DutyC1,uint16_t DutyC2,uint16_t DutyC3,uint16_t DutyC4){ static uint16_t lastDuty1=0,lastDuty2=0,lastDuty3=0,lastDuty4=0; //DutyC1 = DutyC1>eriod_Max?Period_MaxutyC1; //DutyC2 = DutyC2>eriod_Max?Period_MaxutyC2; //DutyC3 = DutyC3>eriod_Max?Period_MaxutyC3; //DutyC4 = DutyC4>eriod_Max?Period_MaxutyC4;//校正 if(lastDuty1!=DutyC1){TIM2->CCR2 = DutyC1;lastDuty1=DutyC1;} if(lastDuty2!=DutyC2){TIM2->CCR1 = DutyC2;lastDuty2=DutyC2;} if(lastDuty3!=DutyC3){TIM2->CCR3 = DutyC3;lastDuty3=DutyC3;} if(lastDuty4!=DutyC4){TIM2->CCR4 = DutyC4;lastDuty4=DutyC4;}//更新占空比 } 这是程序用的是ANO 四轴的板子我在主程序里 设置了一个 static uin16_t PID;一段时间内 PID+=10Motor_Working(PID,PID,PID,PID);这样PID=10风扇转大概2秒左右 程序就死了 风扇还在转 但是不往下执行也就是不再自加 其他的判断指令也不运行。这个是什么情况呢
2019-05-08 05:45
CY8CKIT-04942XXKIT以前工作过。最近，它没有得到MyWi7PC的认可。附加的屏幕截图显示了插入板后发生的事情。我可以使用MIXPROP3编程板，但我想使用USB串行端口。请帮忙。没有司机27.6 KUSB串行25.4 K没有端口46.3 K设备管理器84.1 K 以上来自于百度翻译 以下为原文The CY8CKIT-049-42xx kit was working before. Recently, it is not getting recognized by my Win7 PC. Attached screen shots show what is happening after the board is inserted. I can program the board using MiniProg3, but I want to use USB Serial port. Please help. No Driver.PNG 27.6 KUSB Serial.PNG 25.4 KNo Port.PNG 46.3 KDevice Manager.PNG 84.1 K
2019-01-23 07:32
求大佬分享兄弟打印机故障代码表
2021-11-15 06:52
PLC和PC基于工业以太网通信研究与实现，不看肯定后悔
2021-05-28 06:35
什么是文本事件抽取？
2021-09-18 06:34
