Casio Micro-Mini M-800  
Written by Accutron on 2017-03-10  

Measuring only 62mm in its largest dimension, the Casio Micro-Mini M-800 is an early example of an ultra-miniature four-function calculator. The 'matchbox' form factor of the M800 was a novel but short-lived design approach. While the front-facing dimensions of the M-800 are impractically small, the calculator is 14mm thick, accommodating two stacked PCBs and a button cell. The M-800 and its matchbox siblings were quickly superseded by ultra-thin 'credit card' calculators, primarily made possible by the introduction of solar power and coin cells.

The M-800 was manufactured in no less than five different finishes. The exampled pictured here is a mottled silver variation.


Casio Micro-Mini M-800 handheld four-function calculator.


Micro-Mini M-800, internal construction. The M-800 is based on a NEC D870G single-chip calculator.

This article is part of the [Electronic Calculators] exhibit.

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