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Create a basic flowchart - Visio. Create a flowchartStart Visio.Click the Flowchart category.Double-click Basic Flowchart.For each step in the process that you are documenting, drag a flowchart shape onto your drawing.Connect the flowchart shapes by holding the mouse pointer over the first shape, and then clicking the small arrow that appears that points to the shape you want to connect to.

Create a basic flowchart - Visio

If the second shape is not directly across from the first shape, click and hold the small arrow, drag it to the second shape, and drop the connector in the middle of the second shape.To add text to a shape or connector, select it, and then type. When you are finished typing, click on a blank area of the page.To change the direction of a connector's arrow, select the connector, and then, on the Shape tab, in the Shape Styles group, click Line, point to Arrows, and select the arrow direction and style that you want. Fix alignment and spacing What the flowchart shapes represent What the flowchart shapes represent Create a flowchart 1. 2.

Flowchart Maker & Online Diagram Software. Untitled. Introduction to Counter/Timers Counter/timer hardware is a crucial component of most embedded systems.

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Introduction to Watchdog Timers. Introduction to Watchdog Timers For those embedded systems that can't be constantly watched by a human, watchdog timers may be the solution.

Introduction to Watchdog Timers

Most embedded systems need to be self-reliant. It's not usually possible to wait for someone to reboot them if the software hangs. Some embedded designs, such as space probes, are simply not accessible to human operators. If their software ever hangs, such systems are permanently disabled. A watchdog timer is a piece of hardware that can be used to automatically detect software anomalies and reset the processor if any occur. Figure 1 shows a typical arrangement. Kicking the dog The process of restarting the watchdog timer's counter is sometimes called "kicking the dog.

" A simple example is shown in Listing 1. Listing 1: Kicking the dog uint16 volatile * pWatchdog = (uint16 volatile *) 0xFF0000; main(void) { hwinit(); for (;;) { *pWatchdog = 10000; read_sensors(); control_motor(); display_status(); } } Software anomalies Karate lessons Dog days 1. Sign in or Register. Embedded Software in C for an ARM Cortex M. Embedded Software in C for an ARM Cortex M Jonathan W.

Embedded Software in C for an ARM Cortex M

Valvano and Ramesh Yerraballi (1/2015) Chapter 1: Program Structure A sample program introduces C C is a free field language Precedence of the operator determines the order of operationComments are used to document the software Preprocessor directives are special operations that occur first Global declarations provide modular building blocks Declarations are the basic operations Function declarations allow for one routine to call another Compound statements are the more complex operations Global variables are permanent and can be shared Local variables are temporary and are private Source files make it easier to maintain large projects Chapter 2: Tokens ASCII characters Literals include numbers characters and strings Keywords are predefined Names are user defined Punctuation marks Operators Chapter 3: Literals include numbers characters and strings. Serial Communication. Favorited Favorite 37 Introduction Embedded electronics is all about interlinking circuits (processors or other integrated circuits) to create a symbiotic system.

Serial Communication

In order for those individual circuits to swap their information, they must share a common communication protocol. Hundreds of communication protocols have been defined to achieve this data exchange, and, in general, each can be separated into one of two categories: parallel or serial. Parallel vs. Parallel interfaces transfer multiple bits at the same time. An 8-bit data bus, controlled by a clock, transmitting a byte every clock pulse. 9 wires are used. Serial interfaces stream their data, one single bit at a time. Example of a serial interface, transmitting one bit every clock pulse. Think of the two interfaces as a stream of cars: a parallel interface would be the 8+ lane mega-highway, while a serial interface is more like a two-lane rural country road.

Parallel communication certainly has its benefits. Asynchronous Serial. How to Read a Schematic. Favorited Favorite 39 Overview Schematics are our map to designing, building, and troubleshooting circuits.

How to Read a Schematic

Understanding how to read and follow schematics is an important skill for any electronics engineer. This tutorial should turn you into a fully literate schematic reader! We’ll go over all of the fundamental schematic symbols: Chapter 6: Parallel I/O ports. How to Use C's volatile Keyword. By Nigel Jones The proper use of C's volatile keyword is poorly understood by many programmers.

How to Use C's volatile Keyword

This is not surprising, as most C texts dismiss it in a sentence or two. This article will teach you the proper way to do it. Have you experienced any of the following in your C or C++ embedded code? Code that works fine--until you enable compiler optimizations Code that works fine--until interrupts are enabled Flaky hardware drivers RTOS tasks that work fine in isolation--until some other task is spawned If you answered yes to any of the above, it's likely that you didn't use the C keyword volatile. Declaration - Why is volatile needed in C?