Introduction: Sinclair Scientific Calculator Simulator With Arduino Uno

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The goal of this project is to run the following simulator http://righto.com/sinclair on an Arduino Uno with TFTLCD, Touch Screen and SD Card Module resembling the original Sinclair Scientific Calculator.

You might find all history of the original device and its hacking story in Mr. Ken Shirriff's amazing blog.

In the 1970s, calculators were the most advanced technological devices available to everyone. But scientific calculators were very rare and valuable.
You might try this simulator to experience a feeling of those days.

Step 1: Materials Required

  1. Arduino Uno or compatible.

  2. TFTLCD Shield with Touch Screen and SD Card module for Arduino Uno.

  3. Micro SD Card.

Step 2: Combine Arduino Uno With TFTLCD Shield

Before attaching the shield to Arduino Uno, check the pin out of the shield is matching the part given in the picture above.

If there is any difference, you need to arrange the pin definitions in the sketch according to your shield.

Attach TFTLCD Shield to the Arduino Uno.

Step 3: Prepare the SD Card

Copy "CalFace0.bmp" file to the root folder of the SD Card on your PC.

(The library supports the FAT16 and FAT32 filesystems, but use FAT16 formatted SD Card when possible.)

Bitmap file is given in the next step.

Insert SD Card to the slot on the shield.

Step 4: Download Software and Libraries

Download software and copy to your Arduino working directory.

"C:\Users\"YourUserName"\Documents\Arduino\"

Libraries are also included in this package. If necessary, copy libraries to your working library folder.

"C:\Users\"YourUserName"\Documents\Arduino\libraries\"

"CalFace0.bmp" file is in the "CalculatorFace" folder.

Attachments

Step 5: Compile and Upload the Simulator Software

Step 6: Using the Simulator

  • Touch the left side of the "Power Switch" to run the simulator in slow speed.(Default mode) Blue dot at the top left corner of the screen is indicating the slow speed. All calculation steps are visible in this mode.
  • Touch the right side of the "Power Switch" to run the simulator in full speed which is compatible with the real hardware. Green dot at the top left corner of the screen indicates the full speed.

    Calculation steps are not visible in this mode. Splitting of the Power Switch area seems odd but compatible with the remaining of the keypad.

  • Blue dot on the top right corner indicates that numeric entry is accepted.
  • Grey dot on the top right corner indicates that function entry is accepted and calculation is in progress.
  • If SD Card is not inserted, LCD will display red color in full screen.
  • If "CalFace0.bmp" file is not present on the SD Card, LCD will display blue color in full screen.

Step 7: Quick Start Guide

This sheet is a reproduction of the original "Quick Start Guide" provided with Sinclair Scientific Calculator.

Complete "Operating Instructions" manual is available on the Internet. Just search with Google.

Step 8: Using Different Devices/libraries

If you want use different LCDTFT and Touch Screen devices with SPI/I2C interfaces, you might make your adaptations. I included my comments and cautions in the header section of the "SinclairScientificCalc.ino" file. Please read that section.

Have fun.