[1] In the former, the PC-1403 would behave like a normal scientific calculator at the time with formulas entered in algebraic logic.

In RUN mode, BASIC statements could be entered for immediate execution and print out.

The latter was similar to the Direct algebraic logic employed by modern calculators.

The programming model employed was unstructured BASIC for which the PC-1403 distinguished between RUN and PRO mode.

It can be called by entering a number or an expression followed by pressing DEF F (in run mode).