PC-BASED CANDLE IGNITOR
Here is a simple but very interesting pc based electronics project for computer student. Lighting candle using PC, which lets you to light up candle by pressing simple enter key. The project PC based candle ignitor seems most useful at the time of occasion like birthday, anniversary etc. for giving surprise.
The whole circuit of PC based candle ignitor is dividing two main parts, Hardware and Software.
Hardware:- The hardware section of PC based candle ignitor is built and fabricated around most popular and versatile IC, timer IC (555) configured as monostable multivibrator. A 25 pin ‘D’ type male parallel port is used for interface between computer and driver circuit section. Where transistor T1 is connected to pin 2 of parallel poet through resistor R1. Output of transistor T1 is connected to trigger pin pin2 of IC1 through coupling capacitor C3. The output of IC1 is given to the base of transistor T2 through resistor R4, where transistor T2 is used as relay driver.
Software:- The software written for this project is in “C” language in order to make the project PC based candle ignitor simple and easy. As shown in below code the address 378H of parallel port LPT1 is used.
/* PROGRAMME TO LIGHT PC-BASED CANDLE */
cprintf("By DREAMLOVER TECHNOLOGY, WWW.ELECTRONICSPROJECT.ORG");
cprintf("Press enter to light up the "CANDLE" ");
Working of the circuit
Whenever the key “ENTER” is pressed Data bit D0 is send from computer to circuit through pin 2 of parallel port. The high output from computer is inverted by transistor T1 in order to trigger IC1. Further, high output is obtained from pin 3 and given to base of transistor T2 through resistor R4 for about 50 second in order to energized relay RL1 where, relay is used as switch of heating coil.
Resistors (all ¼-watt, ± 5% Carbon)
R1, R4 = 1 KΩ
R2 = 2.7 KΩ
R3 = 10 KΩ
VR1 = 1 MΩ
C1 = 47 µF/16V
C2 = 0.01 µF
C3 = 0.1 µF
IC1 = NE555 (Timer IC)
T1, T2 = BC548
D1 = 1N4001
RL1= 6V, 100W, 1C/O Relay
25 pin “D” type parallel port