1. Introduction
This manual provides essential instructions for the proper setup, operation, and maintenance of your Casio FX-5800P Scientific Programmable Calculator. Designed for advanced mathematical and scientific computations, this calculator offers a wide range of functions and programmability to assist users in various academic and professional fields. Please read this manual thoroughly to ensure optimal performance and longevity of your device.

Image 1.1: Front view of the Casio FX-5800P Scientific Programmable Calculator, displaying its screen and key layout.
2. Setup
2.1 Battery Installation
The Casio FX-5800P calculator operates on one standard AAA battery. To install or replace the battery:
- Locate the battery compartment cover on the back of the calculator. This cover is designed for easy access without fully opening the back panel.
- Slide the cover off in the direction indicated by the arrow.
- Insert one AAA battery, ensuring the positive (+) and negative (-) terminals are correctly aligned as shown inside the compartment. If a plastic strip is present, remove it before inserting the battery.
- Replace the battery compartment cover, ensuring it clicks securely into place.
2.2 Initial Power On and Reset
After installing the battery, do not immediately power on the calculator. First, perform a reset to prevent potential malfunctions:
- Locate the small 'P' button on the back of the calculator.
- Using a thin, pointed object (like a paperclip), gently press the 'P' button. This will reset the calculator to its factory default settings.
- You may now press the ON button to power on the calculator.
2.3 Display Contrast Adjustment
If the display is too dim or too dark, adjust the contrast:
- Press SHIFT then MODE SETUP to enter the setup menu.
- Navigate to the contrast setting (refer to the on-screen menu or the full user manual for exact navigation).
- Use the arrow keys to adjust the contrast to a comfortable level.
3. Operating Instructions
The Casio FX-5800P offers 664 functions, 26 to 2398 variables, 40 scientific constants, and 128 built-in formulas. Its natural input system allows you to enter equations as they appear in textbooks.
3.1 Basic Operations
- Power On/Off: Press ON to turn on. Press SHIFT then OFF (AC) to turn off.
- Input: Enter numbers and operations using the keypad. The display shows expressions as you type.
- Execute: Press EXE to execute a calculation.
- Correction: Use the left/right arrow keys to move the cursor and DEL to delete characters.
3.2 Advanced Functions
The calculator supports a wide array of advanced calculations:
- Programmability: Utilize the 28KB program memory for Basic-like programming (e.g., IF statements) to automate repetitive calculations.
- Data Transmission: Connect two FX-5800P calculators using a 3-pin cable for data exchange.
- Scientific Constants & Formulas: Access 40 scientific constants and 128 built-in formulas directly.
- Calculus: Perform probability, permutation, combination, and random number calculations.
- Statistics: Conduct list-based statistics, standard deviation, and regression analysis.
- Equations: Solve systems of linear equations (2 or 3 unknowns) and polynomial equations (2nd or 3rd degree).
- Matrices: Perform matrix calculations.
- Complex Numbers & Trigonometry: Handle complex number calculations and trigonometric functions.
- Fractions: Automatic fraction calculations are supported.
- Value Tables: Generate numerical and recursive value tables.

Image 3.1: The Casio FX-5800P calculator positioned on a desk alongside engineering blueprints and drafting tools, illustrating its use in professional environments.
4. Maintenance
4.1 Cleaning
To maintain the calculator's appearance and functionality:
- Wipe the exterior with a soft, dry cloth.
- For stubborn dirt, slightly dampen the cloth with water and a mild detergent, then wipe dry immediately.
- Avoid using strong solvents, abrasive cleaners, or spraying liquids directly onto the calculator.
4.2 Battery Replacement
Refer to Section 2.1 for detailed instructions on replacing the AAA battery. Replace the battery promptly when the display becomes dim or erratic.
4.3 Storage
When not in use, store the calculator in its slide-on hard case to protect it from dust, scratches, and impacts. While the cover is designed for protection, handle it with care as it may be thin. Avoid exposing the calculator to extreme temperatures, humidity, or direct sunlight for prolonged periods.
5. Troubleshooting
If you encounter issues with your Casio FX-5800P, try the following solutions:
- Calculator does not turn on: Check if the battery is correctly installed and has sufficient charge. Replace the battery if necessary.
- Display is dim or unreadable: Adjust the display contrast (refer to Section 2.3). If the issue persists, replace the battery.
- Calculator behaves erratically or freezes: Perform a full reset by pressing the 'P' button on the back of the calculator (refer to Section 2.2). Note that this will clear all memory and settings.
- Calculation errors: Double-check your input and ensure the correct mode is selected for your calculation type. Refer to the operating instructions for specific function usage.
If these steps do not resolve the problem, please contact Casio customer care for further assistance.
6. Specifications
| Feature | Detail |
|---|---|
| Model Number | FX-5800P |
| Type | Scientific Programmable Calculator |
| Display | Dot Matrix, Natural Display, 4 lines x 16 characters |
| Functions | 664 Functions |
| Variables | 26 to 2398 |
| Scientific Constants | 40 |
| Built-in Formulas | 128 |
| Program Memory | 28 KB |
| Power Source | 1 x AAA Battery |
| Dimensions (LxWxH) | 16.3 x 8.1 x 1.5 cm |
| Weight | 150 g |
| Material | Plastic |
| Color | Black |
| Country of Origin | China |
| Included Components | 1 Calculator, 1 Warranty Card, 1 Warranty Term Sheet, 1 User Manual |

Image 6.1: The Casio FX-5800P calculator with its key dimensions (length and width) indicated, providing a visual reference for its size.
7. Warranty and Support
7.1 Manufacturer Warranty
Your Casio FX-5800P Scientific Programmable Calculator comes with a 3 Years All India Manufacturer Warranty. Please retain your warranty card and proof of purchase for any warranty claims.
7.2 Customer Support
For any warranty, service-related issues, or technical assistance, please reach out to Casio customer care. Contact information can typically be found on the Casio India website or on the warranty term sheet included with your product.
Manufacturer: Casio India Co Pvt Ltd, A-41, 1st Floor, MCIE, Mathura Road, New Delhi-110044
Importer: Imported By - Casio India Co Pvt Ltd, A-41, 1st Floor, MCIE, Mathura Road, New Delhi-110044







