Editing Sharp PC-1403

{{More citations needed|date=December 2009}}
{{anchor|EL-5500III}}{{ Infobox Calculator
| name         = Sharp PC-1403
| image        = Sharp_pc_1403.jpg
| caption      = Sharp PC-1403 handheld BASIC computer
| type         = [[Pocket computer]] 
| entry        = [[Calculator_input_methods#Infix_notation|Infix]],  [[Calculator_input_methods#BASIC_notation|BASIC]],
| introduced   = 1986
| discontinued =
| processor    = CPU: Hitachi SC61860 (8-bit CMOS)
| frequency    = 768&nbsp;kHz
| display_type = [[LCD]] [[dot-matrix]]
| display_size = 24 characters
| prog_lang    = [[Unstructured BASIC]]
| memory_user  = 8&nbsp;KB
| memory_rom   = 72&nbsp;KB 
| ports        = 1x proprietary (11 pins)
| supply       = 2x CR2032
| power        = 0.03&nbsp;W
| weight       = 
| dimensions   = 
}}
The '''Sharp PC-1403''' was a small [[scientific calculator]] and [[pocket computer]] manufactured by [[Sharp Corporation|Sharp]]. It was the successor of the [[Sharp PC-1401]], and had better display, more RAM and better system software.

==Technical specifications==
{| class="wikitable"
| [[Image:Sharp PC-1403H front.jpg|thumb]]
| [[Image:Sharp PC-1403H rear.jpg|thumb]]
|}

* CPU: Hitachi SC61860 (8-bit CMOS) 768&nbsp;kHz
* Memory: 8&nbsp;KB [[RAM]] (6863 bytes available), 72&nbsp;KB ROM; 32&nbsp;KB RAM in '''PC-1403H''' model
* Display: Monochrome [[LCD]] 1 line with 24 5×7 characters
* Power: 6&nbsp;V DC - 2× CR2032, 0.03&nbsp;W
* Connector (11 pins) for external devices
* Integrated speaker (4&nbsp;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''.<ref name="Sharp_1986_PC-1403">{{cite book |title=SHARP Pocket Computer Model PC-1403 - Operation Manuel | publisher=[[Sharp Electronics]] / [[Sharp Corporation]] |location=Osaka, Japan |date=1986| url=http://pocketcomputerworld.free.fr/Manuals/PC-1403.pdf|archive-url=https://web.archive.org/web/20160910064809/http://pocketcomputerworld.free.fr/Manuals/PC-1403.pdf | archive-date=10 September 2016| url-status=live}}</ref> In the former, the PC-1403 would behave like a normal scientific calculator at the time with formulas entered in [[Calculator input methods#Immediate execution |algebraic logic]]. In ''RUN'' mode, [[Calculator input methods#BASIC notation|BASIC statements]] could be entered for immediate execution and print out. The latter was similar to the [[Calculator input methods#Infix notation|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 later 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 <code>DEF</code> <code>F</code> (in run mode).
 
<syntaxhighlight lang="QBasic">
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
</syntaxhighlight>

===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==
{{reflist}}

{{Sharp Corporation}}
{{Dynabook Inc.}}
{{DEFAULTSORT:Sharp Pc-1403}}
[[Category:Sharp pocket computers|PC-1403]]
[[Category:Sharp programmable calculators|PC-1403]]

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