This instructable is part of my Book playing with parallel port . in this instructable we will going to learn about Turbo c communication with parallel port . lets start ..

part to be required

1.LED (Light Emitting Diode)

2.Jumper wires

3.Bread board

4.Parallel Port

Step 1: Make Circuit With Parallel Port and Leds

with help of soldering iron. solder Leds on parallel port pins make a pcb circuit as per 2d diagram shown in schematic diagram,

Step 2: Program for Blink 7 Leds in Sequnce

plug parallel port to pc and run below program in turbo c compiler .

#include <stdio.h>


#include <math.h>

void main()


int i;









Step 3: Explore More

Make your own Clickable Mouse GUI with Turbo c to Control DC and Stepper motor . Learn to make Motor driven circuit , prototype design with parallel port . Buy Book now Available in Kindle store

What you will learn
1. Development of GUI for controlling 7 led in different sequence.

2. Development of GUI for Controlling Dc motor.

3. Development of GUI for Controlling Stepper motor.

4. Making of Motor driven circuit.

5. Making of prototype to control output device with turbo c and parallel port.


<p>When you drive LEDs, they require current limiting resistors to keep from damaging the port IC, which is usually a 74xx244, 245 or LSI port IC. Without them, the circuit works initially because it is using the IC's internal pullup resistor to limit the current, but they aren't designed to dissipate that amount of power for very long. There are alternative LEDs that I recommend to everyone: HLMP-1600. These are T-1 red LED which have built-in current limiting resistors. They are ideal for protoboard use so you don't have to run wires from an IC to the resistor, then more wires to the LED. They work very well with 5V TTL outputs as well as 3V3 circuits, while protecting them. </p><p>Also, TTL, LS and AS outputs tend to be much more suited for sinking current, rather than sourcing current. [e.g. | TTL output |-----|&lt;|------[ R330 ]------- +5V ] The logic seems 'inverted' as the LED comes on at logic low, but this works really great for opto-isolators, which then protect your computer's parallel port upwards of 5Kv of isolation from your real-world circuitry. A MOC3020 opto triac can be used to switch a full power triac at 120 or 220 Vac for motors, lamps, Christmas light strings, etc.</p><p>Thanks for the project, and best wishes!</p>

About This Instructable



Bio: Mechatronics engineer Author ( Arduino + Visual Basic 6.0: Make your own software to control Arduino Robots ) Twitter account @ujashpatel
More by ujash patel:Make Electromagnetic /magnetic Field Detector with arduino PLAYING WITH PARALLEL PORT (MAKE YOUR OWN GUI WITH TURBO C TO CONTROL YOUR ROBOT Control Arduino with visual basic 6.0 
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