Atari Calculator#

the Atari Calculator is an advanced programmable calculator that supports both RPN and ALG arithmetic.

Disk Image: Atari Calculator/Calculator.atr(info)
Handbook: Atari Calculator/Atari_Calculator_Manual_Optimized.pdf(info)
http://strotmann.de/~cas/download/atari/Atari_Calculator_Manual_Original.pdf.gz