I recently found a interesting calculator. It is covered with sheet aluminum and has a green LED display it reads "Unisonic 890" on the housing. Upon putting in 4 AA batteries and turning this calculator on I noticed something unusual. I type [9] [X] [9] [=] and it reads "81", If i type [9] [/] [3] [=] it reads "3", thats normal. But typing [6] [-] [3] [=] it reads "-3"
If I type [6] [=] [3] [-] it reads "3" I only works correctly if I put in the multiplication and division algebraically and input the addition and subtraction using RPN.
What the heck? Was this calculator designed to do this? or is it broken? If it is "broken" I want to "brake" it more so the multiplication and division is RPN too!
ARUID