PC COTROL STEPPER MOTOR is our major project. This project is also known as hotel management system. In this project we can control any type of appliance by using our PC. This project is very important for PC communication with machinery. With the help of this project we can control the all our factory machines with our PC without the need of any control panel there will a small control panel for control of different switches. We need to make a small program in gauges or other lain this program we will control the appliances with parallel port moreover we will use wireless technology. For wireless system, we will use RF technology. We will attached RF txer and RF rxer with the PC’s Parallel port and RF Rxer with different relays and Devices .we will use optocoupler at the end of PC parallel port.
We know that today is the world of automation. There is increasing competition making it necessary to make it necessary to use reliable, low cost and accurate automatic system. With the help of this project we can control the all our factory machines with our PC without the need of any control panel there will a small control panel for control of different switches. We need to make a small program in C_++. In this program we will control the appliances with parallel port moreover we will use wireless technology. For wireless system, we will use RF technology. We will attach RF txer and RF rxer with the PC’s Parallel port and RF Rxer with different relays and Devices .we will use optocoupler at the end of PC parallel port.
| Interfacing to the IBM-PC Parallel Printer Port |
First component of this project is opto-coupler. IN this project we use IC 817 as a opto coupler. 817 is a 4 pin IC. Pin no 1 and 2 is input pin and pin 3 and 4 is the output pin. Pin no 1 is connected to the input signal and pin no 4 is acts as an output pin. When high signal is connected on the pin no 1 then Internal infra red led connected to the pin no 1 is switch on and so focus on the photodiode connected inside the optocoupler. Now due to this optocoupler is on and negative output is available on the pin no 3. This negative output is connected to the inverter IC. Note that in this project we use four optocoupler circuits to control the four output circuit. So when all the signal is coming then four output from the optocoupler is connected to the inverter circuit. We use an inverter in this project because we require a positive output at a result. Inverter in this project converts the negative voltage into positive voltage.
Pin no 1 of the IC 4049 (inverter) is connected to the positive supply. Pin no 8 of the circuit is connected to the negative supply. Pin no 3, 5, 7,9,11 is the input pins of this ic. Pin no 2,4,6,10,12 is the output pin no this ic. Signal from the optocoupler is connected to the pin no 3,5,7,9 and output is available on the pin no 2, 4,6,10. At the input point of inverter we connect four resistances on each point to give a reverse voltage on the input pinsHere NPN transistor works as a switch in this project. Now when positive signal is connected to the base of NPN transistor, then NPN is on and relay connected to the collector point is also on. PARALLEL PORT OPERATION
The original IBM-PC’s Parallel Printer Port had a total of 12 digital outputs and 5 digital inputs accessed via 3 consecutive 8-bit ports in the processor’s I/O space.
- 8 output pins accessed via the DATA Port.
- 5 input pins (one inverted) accessed via the STATUS Port.
- 4 output pins (three inverted) accessed via the CONTROL Port.
- The remaining 8 pins are grounded.
