How can you add extra hardware UARTs to a 32bit TMS470 ARM7-based microcontroller at zero cost? Solution: Designers can use the high-end timer (HET) peripheral found on all Texas Instruments ARM7-based, 32-bit TMS470 microcontrollers to implement add…

In my older blog "PIC32MZ tutorial -- Key Debounce", I shows how to acheive key debounce with port polling. At this moment, I write an application which uses External Interrupt.  Therefore, only generates interrupt and starts debounce when the f…

External Input Counter and External interrupt : count the input signal from the button. So what is the different between two methods ? While external interrupt needs to jump into the interrupt routine to do the increment or decrement of a variable, c…

外部中斷(External Interupt) 在MCU中是很常見而且很常用到的基本function,所以就不多做解釋.不過因為每顆MCU的配置都不太一樣所以在此記錄下來. External Interrupt 配置 void EXIT_GPIO_Config(void) { GPIO_InitTypeDef GPIO_Config; EXTI_InitTypeDef EXTI_Config; NVIC_InitTypeDef NVIC_Config; RCC_AHB1PeriphClockCm…

note 1:  Several interrupts can be pending at the same time. When an interrupt request is not serviced immediately, it is latched and then processed when its software priority combined with the hardware priority becomes the highest one. note 2: From…

PWM输入检测是输入捕获的一个特例,可以测量频率与占空比 与输入捕获不同的是PWM输入模式会将同一个输入信号(TI1或TI2)连接到两个捕获装置(IC1和IC2).这两个捕获装置一个捕获上升沿一个捕获下降沿.TI1FP1.TI2FP2它们中的一个被选择为触发输入且从模式控制器被配置为复位模式. 注意:只有TI1FP1和TI2FP2连到了从模式控制器,所以PWM输入模式只能使用TIMx_CH1 /TIMx_CH2信号. //Timer4 CH2测周期,CH1测占空比,PB7引脚来输入 //这个捕捉…

EXTI控制器的主要特点如下: 每个中断/事件线上的独立触发器和掩码 每个中断行的专用状态位 生成最多20个软件事件/中断请求 脉冲宽度小于APB2时钟周期的外部信号检测. 每条中断线路的专用状态位生成最多20个软件事件/中断请求检测脉冲宽度小于APB 2时钟周期的外部信号.…

Shared Peripheral Interrupts (SPI) SPI 可以接收来自PL的中断,这里使用PL模块 AXI Timer 的中断模式,并连接到CPU. AXI TIMER 定时器,内部有两个完全相同的TIMER模块. 特性: 在手册里可以找到详细的参数和寄存器信息. 硬件系统 需要zynq核和一个AXI Timer,PL的clock可以在zynq核内部设置. 软件部分 这里会使用到xilinx提供的函数库 中断       xscugic.h 定时器 xtmrctr.h 因为使…

Timers get their clock source from External pins or Internal timer sources. External External = pins: TI1 or TI2 or ETR set pin to be used: in TIMx_CCMR1 reg - set pin to be used by writing CCxS bits select polarity of input in TIMx_CCER reg - write…

void TIMER0_IRQHandler (void) { if(LPC_TIM0->IR & 0x01) { LPC_GPIO1->FIOPIN ^= ( << ); LPC_TIM0->IR = 0x01; } } /* * CPU : LPC1769 * Operate Frequency : 120MHz * Timer Interrupt Example : * TCR : Counter Enable/Disable * PR : PreScale r…

1.UART原理说明 发送数据时,CPU将并行数据写入UART,UART按照一定的格式在一根电线上串行发出:接收数据时,UART检测另一根电线上的信号,串行收集然后放在缓冲区中,CPU即可读取UART获得这些数据.UART之间以全双工方式传输数据,最精确的连线方法只有3根电线:TxD用于发送数据,RxD用于接收数据,Gnd用于给双发提供参考电平,连线如下: UART使用标准的TTL/CMOS逻辑电平(0~5v.0~3.3v.0~2.5v或0~1.8v)来表示数据,高电平表示1,低电平表示0.为了…

7.1 介绍 UART(Universal Asynchronous Receiver Transmitter),通用异步收发器,用来传输穿行数据时 UART 之间以全双工方式传输数据,连线方法只有 3 根电线:TXD 用于发送数据,RXD 用于接收数据,GND用于给双方提供参考地. 串口数据线以 “位”为最小单位传输数据.帧(frame)由具有完整意义的.不可分割的若干位组成,它包含开始位.数据位.校验位和停止位. UART 使用标准的 TTL/CMOS 逻辑电平(0~5V.0~3.3V.0~…

今天我来讲讲PWM触发ADC的例程 /**************************************************************************** * @file main.c * @version V2.0 * $Revision: 5 $ * $Date: 14/06/30 4:51p $ * @brief Demonstrate how to trigger ADC by PWM. * @note * Copyright (C) 2014 Nuv…

Low-cost, 8-bit, single-chip microcontrollers are stingy when it comes to on-chip PWM (pulse-width-modulation) resources. The use of a PWM resource often forces a designer to sacrifice a capture/compare or timer channel because the PWM channel shares…

M451提供了两路PWM发生器.每路PWM支持6通道PWM输出或输入捕捉.有一个12位的预分频器把时钟源分频后输入给16位的计数器,另外还有一个16位的比较器.PWM计数器支持向上,向下,上下计数方式.PWM用比较器和计数器的比较来产生事件,这些事件用来产生PWM脉冲,中断,EADC/DAC转换触发信号. PWM发生器支持两种标准PWM输出模式:独立模式和互补模式,它们的架构不同.标准输出模式又有两种输出功能:组功能和同步功能.组功能可以在独立模式和互补模式下使能.同步功能只有在互补模式下才可以…

原文http://blog.chinaunix.net/uid-14114479-id-3125685.html ARM驱动蜂鸣器的方式有两种:一种是PWM输出口直接驱动,另一种是利用IO定时翻转电平产生驱动波形对蜂鸣器进行驱动.PWM输出口直接驱动是利用PWM输出口本身可以输出一定的方波来进行驱动.在ARM中可以用几个特殊功能寄存器对占空比和周期进行设置.通过设置这些寄存器产生符合蜂鸣器要求的方波后,这个时候利用这个方波就可以对蜂鸣器进行驱动了.使用PWM时,通过TCMPn可以决定脉宽,TCN…

STM32F4 External interrupts Each STM32F4 device has 23 external interrupt or event sources. They are split into 2 sections. First interrupt section is for external pins (P0 to P15) on each port, and other section is for other events, like RTC interru…

PWM_T Struct Reference Control Register » Pulse Width Modulation Controller(PWM)   typedef struct { /** * @var PWM_T::CTL0 * Offset: 0x00 PWM Control Register 0 * ---------------------------------------------------------------------------------------…

In one embodiment, a method includes transitioning control to a virtual machine (VM) from a virtual machine monitor (VMM), determining that a VMM timer indicator is set to an enabling value, and identifying a VMM timer value configured by the VMM. Th…

BACKGROUND The present disclosure relates to the handling of interrupts in a environment that utilizes virtual machines, and, more specifically, to the steering of interrupts between multiple logical processors running virtual machines. The virtualiz…

The microcontroller is PIC32MZ2048ECH144 on the PIC32MZ EC Starter Kit. This microcontroller has four 32-bit synchronous timers are available by combining Timer2 with Timer3, Timer4 with Timer5, Timer6 with Timer7, and Timer8 with Timer9. The 32-bit…

UART简介: UART(Universal Asynchronous Receiver and Transmitter)通用异步收发器(异步串行通信口),是一种通用的数据通信协议,它包括了RS232.RS499.RS423.RS422和RS485等接口标准规范和总线标准规范,即UART是异步串行通信口的总称.而RS232.RS499.RS423.RS422和RS485等,是对应各种异步串行通信口的接口标准和总线标准,它规定了通信口的电气特性.传输速率.连接特性和接口的机械特性等内容,这些东东都…

The STM32F4xx are able to handle external or internal events in order to wake up the core (WFE). The wakeup event can be generated either by: (I've removed normal external interrupt mode details) or configuring an external or internal EXTI line in ev…

A computer system is described having one or more host processors, a host chipset and an input/output (I/O) subsystem. The host processors are connected to the host chipset by a host bus. The host chipset is connected to the input/output subsystem by…

BACKGROUND OF THE INVENTION This relates to Input/Output (I/O) performance in a host system having multiple processors, and more particularly, to efficient usage of multiple processors in handling I/O completions by using interrupt affinity schemes t…

UART是工程师在开发调试时最常用的工具的,其通信协议简单.opencores 网站提供了兼容16550a的UART IP其基本特性如下: uart16550 is a 16550 compatible (mostly) UART core. The bus interface is WISHBONE SoC bus Rev. B. Features all the standard options of the 16550 UART: FIFO based operation, interru…

转载请注明:@小五义 http://www.cnblogs.com/xiaowuyi            欢迎加入讨论群 64770604 一.实验器材 1.TPYboard V102板  一块 2.LED灯   一个 3.1602 屏 一块 二.重力传感器 TPYboard与pyboard一样,本身带一个重力传感器.该传感器能够感知到加速力的变化.加速力就是当物体在加速过程中作用在物体上的力,比如晃动.跌落.上升.下降等各种移动变化都能被转化为电信号. TPYBoard使用的是MMA7660…

Software Testing Part I:The Big Picture 1.Software Testing Background Bug's formal definition 1.The software doesn't do something that the product specification says it should do. 2.The software does something that the product specification says it s…

storm定时器与java.util.Timer定时器比较相似.java.util.Timer定时器实际上是个线程,定时调度所拥有的TimerTasks:storm定时器也有一个线程负责调度所拥有的"定时任务".storm定时器的"定时任务"是一个vector类型的数据[time, callback, uuid],内有会有三个值,分别是时间.函数.和uuid,很好理解,时间表示该定时任务什么时候执行,函数表示要执行的函数,uuid用于标识该"定时任务&qu…

RFID读写器的工作原理 RFID的数据采集以读写器为主导,RFID读写器是一种通过无线通信,实现对标签识别和内存数据的读出和写入操作的装置. 读写器又称为阅读器或读头(Reader).查询器(Interrogator).读出装置(Reading Device). 扫描器(Scanner).通信器(Communicator).编程/编码器(Programmer)等等. 读写器工作原理 RFID读写器的基本原理是利用射频信号与空间耦合传输特性,使电子标签与阅读器的耦合元件在射频耦合通道内进行能量传…