Reversing Sinclair's amazing 1974 calculator hack

This is a pretty amazing interactive simulation and supporting explanation of how this little RPN calculator worked.

Link to simulator


Clever Sinclair! Thanks for sharing!


Awesome ! Really great work :D


That is great web page and should be required reading for those that turn out today's GUI PC bloatware.

I have a Sinclair Scientific that I won on Ebay last year for about 15 GBP. First off, I was surprised at how small it is, having only ever seen magazine adverts for it previously. The design is intriguingly minimalistic and, above all, thoughtful. It manages to transcend the cheap build quality.

If it had a couple of digits more accuracy and a deeper stack I wouldn't leave the house without it in my pocket!

I also have a Sinclair Scientific Programmable and that is just plain nasty.


Great read, thanks so much for sharing

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