To Study the 8051 Serial Communication using Fiber optics
- Fiber Optics Digital Transmitter Module– 01
- Fiber Optics Digital Receiver Module– 01
- Plastic Fiber cable 1 meter – 01
- 8051 kit – 02
- Adapter +15V/ DC – 02
- Patch Chords – 04
- PC to PC cable – 02
Kit to Kit communication
Fiber optic digital link was used to transmit and receive the data from one place another place .In this digital link will be supporting 1Mbd speed data communication. It will be act as an optical data modem. So we can use this digital link system in various sectors. And this digital link was used RS 232 serial port for communication.
The heart of the transmitter is a light source. The major function of a light source is to convert an information signal from its electrical form into light. Today’s fiber-optic communications systems use, as a light source, either light-emitting diodes (LEDs) or laser diodes (LDS). Both are miniature semiconductor devices that effectively convert electrical signals into light. They need power-supply connections and modulation circuitry. All these components are usually fabricated in one integrated package.
Transmitting LED HFBR 1251
This type LEDs needs external Driver circuits. Here we used IC 75451 for drive the LED.
The transmission medium in fiber-optic communications systems is an optical fiber. The optical fiber is the transparent flexible filament that guides light from a transmitter to a receiver. An optical information signal entered at the transmitter end of a fiber – optic communications system is delivered to the receiver end by the optical fiber.
Model Diagram for Plastic Fiber cable
This is multi mode plastic fiber cable, in this fiber cable core diameter 1000 micron and fiber cladding index 1.402.
The key component of an optical receiver is its photo detector. The major function of a photo detector is to convert an optical information signal back into an electrical signal (Photocurrent). The photo detector in today’s fiber – optic communications systems is a semiconductor photodiode (PD). This miniature device is usually fabricated together with its electrical circuitry to from an integrated package that provides power-supply connections and signal amplification.
Receiving Photo Diode HFBR 2521
In this type Photo Diode have internal driver circuits. So no need any external driver.
Fiber Optics Digital Transmitter
Fiber Optics Digital Receiver
- ☞Connect +15V adapter to both transmitter and receiver module.
- ☞Switch (sw1) ON the transmitter Module, 8051 kits and receiver module (sw1).
- ☞Connect PC to PC cable between 8051 kit 1 to transmitter module P5 connector and receiver module P8 connecter to 8051 kit 2.
- ☞Connect the 1 m Plastic fiber cable between transmitter modules LED to receiver module Photo Diode.
- ☞Connect P7 and P9 using patch chord at transmitter module.
- ☞Connect P3 and P7 using patch chord at receiver module.
- ☞Now type the transmitter program in transmitter side kit and receiver program in receiver side8051 Kit.
8051 Transmitter Program
|8503||75 8D FD||MOV TH1,#FD|
|8506||75 98 52||MOV SCON,#52|
|8509||D2 8E||SETB TR1|
|850B||74 41||H:MOV A,#41|
|850D||B1 00||ACALL TXMT|
|850F||74 42||MOV A,#42|
|8511||D1 00||ACALL TXMT|
|8513||80 FE||SJMP 8517|
|8600||F5 99||MOV 99,A|
|8602||30 99 FD||JNB 99,8602|
|8605||C2 99||CLR 99|
8051 Receiver Program
|8500||90 87 00||MOV DPTR,#8700|
|8506||75 8D FD||MOV TH1,#FD|
|8509||75 98 52||MOV SCON,#52|
|850C||D2 8E||SETB TR1|
|850E||30 98 FB||JNB RI,850C|
|8511||E5 99||MOV A,99|
|8515||80 F5||SJMP 850C|
|8516||F5 99||MOV SBUF,A|
First execute the receiver side 8051 Kit, then transmitter side 8051 Kit.
☞Now received data verified from 8700 address in receiver side 8051 kit.
Note: You can also write c program to transmit and receive data through fiber optics digital link