Introduction: AriCalculator - a Homemade Handheld Calculator

Picture of AriCalculator - a Homemade Handheld Calculator

The AriCalculator is a DIY calculator or a general purpose handheld device.

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It is battery powered and runs on a NXP S12G240 microcontroller (16-bit, 240k flash, 11k RAM). The device has 38 input keys and a 128x64 pixel LCD display with a backlight option. Three interfaces connect the calculator to the outside world: A BDM debug interface, giving direct access to the microcontrollers on-chip memories and debug features.A USB port, offering a FTDI virtual com port (VCP). This port is under software control and intended to serve as a programming interface.A general purpose SPI port, intended for hardware extensions.The hardware of the of the AriCalculator is already in its third revision. PCB and enclosure have been manufactured by Seeedstudio's Fusion services. The calculator's software is under development. Further information is available here:

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Step 1: Order PCB and Enclosure

Picture of Order PCB and Enclosure

Order the PCB. Fusion compliant Gerber files is available HERE .

Order the laser cut enclosure parts. The SVG source .Available HERE

Step 2: Order Components and Assemble the Hardware

Picture of Order Components and Assemble the Hardware

Order the PCB components as listed in the bill of materials.

Assemble the PCB according to the schematic and assembly plan.

Assemble the enclosure.

Step 3: Upload Software Onto the Calculator

Picture of Upload Software Onto the Calculator

Upload the available software (under development) onto the calculator using a BDM interface such as USBDM or the Mini-BDM-Pod.