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.
Technical specifications
CPU: SC61860 (8-bit CMOS) 768 kHz Memory: 8 KB RAM (6863 bytes available), 72 KB ROM; 32 KB RAM in PC-1403H model Display: Monochrome LCD 1 line with 24 5×7 characters Power: 6 V DC - 2× CR2032, 0.03 W Connector (11 pins) for external devices Integrated speaker (4 kHz beep only) Contrast adjustment wheel Software: Simple BASIC interpreter; calculator mode Matrix calculations
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.
Calculator Calculations could be performed in two modes CAL and RUN. 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.
Programming The programming model employed was unstructured BASIC for which the PC-1403 distinguished between RUN and PRO mode. The latter being used to enter and edit program and the former being used to execute them.
Programming example 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 F 20 F=1 ''Set start value of F to 1 30 FOR I=1 TO N ''counts I from 1 to N 40 F=F*I ''calculates F=F*I 50 NEXT I ''repeats loop from line 40 60 PRINT STR$ N+"!=";F ''print result - i.e. 5!=120. 70 END ''end of program
Machine language programming It is possible to write machine language programs into memory using the POKE command and starting them with the CALL command.
See also Sharp pocket computer character sets
References