The Sharp PC-1403 was a small scientific calculator and pocket computer manufactured by Sharp. It was the successor of the Sharp PC-1401, and had better display, more RAM and better system software.
Manufacturing started in 1986.
It is possible to convert the 1403 to a 1403H by removing the 8 K RAM and soldering in a 32 K RAM. An inverter IC is needed for this, too.
Calculations could be performed in two modes CAL and RUN.[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. The later being used to enter and edit program and the former being used to execute them.
Here is a sample program that computes the factorial of an integer number from 0 to 69. It can be called by entering a number or an expression followed by pressing DEF F (in run mode).
10 "F" AREAD N ''allows to start the program with <expression> DEF F20 F=1 ''Set start value of F to 130 FOR I=1 TO N ''counts I from 1 to N40 F=F*I ''calculates F=F*I50 NEXT I ''repeats loop from line 4060 PRINT STR$ N+"!=";F ''print result - i.e. 5!=120.70 END ''end of programIt is possible to write machine language programs into memory using the POKE command and starting them with the CALL command.