first programmable handheld calculator, 1974.
the hp65 is a very fine machine and well made. it has 100 steps of
merged keystroke program, 9 registers, conditional branches and
subroutines making it more powerful than many modern machines.
the 65 has a built-in magnetic card reader/writer. programs can be
stored on magnetic cards. there is no continuous memory. the right side of
the machine has two small slots. push a card into the bottom slot and it
is pulled through by a small motor and read into the machine. the program
is then ready to use. the card is then removed and slotted into the upper
slot which slides across the front of the machine above the letters A
through E. the front side of the card shows the program definition of
a comprehensive set of supplementary libraries are available as pacs of
magnetic cards. some from third parties.
using the mag cards is way cool. as a means to load up program
libraries it totally blows anything else away. the magnetic card libraries
are themselves tiny. a small plastic box holds something like 40 cards
plus some blanks.
unfortunately the nameplate is missing from the front of this