Clicking your left mouse button on this FLASH Demo link will launch a short (approximately two minute) demonstration of the DIY Calculator expalaining what it is and what it's for.

Note: Make sure your computer's sound system is turned ON when you play this demonstration.

If you have a slow connection and/or if the above presentation doesn't run smoothly, then click your right mouse button on this AVI Demo link, select the "Save Target As" (or similar option) to save the file diycalc-demo.avi to a temporary folder on your system, and then double-click on this file (or use your Windows Media Player) to open and play the movie.

Note: Make sure your computer's sound system is turned ON when you play this demonstration.

This simple introductory DIY Calculator demo program first appeared as an article in the October 2005 issue of the electronics and computing hobbyist magazine Everyday Practical Electronics (EPE).

As discussed in this Introducing the Virtual DIY Calculator article, we provide step-by-step instructions on creating a simple program to read the '0' through '9' and 'A' through 'F' buttons from the calculator's keypad and present these values to the calculator's main display.

Note: If you haven't already purchased our book How Computers Do Math which is accompanyied by a CD-ROM containing the virtual DIY Calculator, you can access a free copy of the DIY Calculator software from the Download page on this site.

In version 4.0.7 of the DIY Calculator we introduced a Workbench utility that comprises two banks of 8-bit switches, a bank of 8-bit light-emitting dfiodes (LEDS), and several different flavors of 7-segment displays.

In addition to discussions as to how switch input devices and LED-based output devices would function in the real world, this Workbench 101 document provides a series of step-by-step labs that guide you through reading from the switches and controlling the various displays.

Note: If you haven't already purchased our book How Computers Do Math which is accompanyied by a CD-ROM containing the virtual DIY Calculator, you can access a free copy of the DIY Calculator software from the Download page on this site.

In order to get a better feel for how the DIY Calculator performs its magic, this demo provides step-by-step instructions showing you how to create and run a program from the ground up. The program we’ve chosen to implement is one that will generate a sequence of pseudo-random numbers in the range 0 through 7. Furthermore, we’re going to include the ability to specify a “seed” value to act as a starting point.

There are many different techniques for generating pseudo-random numbers. One of the simplest methods is to use the concept of a Linear Feedback Shift Register (LFSR), which is the approach we adopt in this LFSR-based Demo.

Note: If you haven't already purchased our book How Computers Do Math which is accompanyied by a CD-ROM containing the virtual DIY Calculator, you can access a free copy of the DIY Calculator software from the Download page on this site.