Mentality of designing of electric fan of infrared remote-control command

Description: The electric fan with remote control underwent extensive research and development in the Pearl River Delta area of Guangdong during the early 1990s. It utilizes a specialized mask chip that serves as the primary management chip. A systematic scheme for receiving and transmitting has been developed using a single-chip computer. The infrared remote control circuit has become a popular design, utilizing an external line remote launch based on Fructus Citri tangerinae. The receiving system employs the 89C2051 microcontroller as the demodulator for the remote control, along with 51 assembly codes. The main program encompasses launching, receiving, command calling, and the procedure for receiving, including a regular interrupt program. This design facilitates the creation of application software.

The electric fan control system consists of two main components: the remote controller and the electric fan control panel. To enable remote operation of the electric fan, an external infrared remote controller is employed. The infrared remote controller typically includes a transmission unit and a receiving unit. The transmission unit consists of a circuit board and the 80C2051 microcontroller. The receiving unit is based on the 89C51 microcontroller and is compatible with MCS-8051 products. It features 2KB of programming flash memory, capable of 1000 write/erase cycles, and operates within a voltage range of 2.7V to 6V. The system exhibits a static behavior of 0Hz to 24MHz, has two levels of program storage encryption, 128 bytes of internal RAM, 15 programmable I/O pins, and six interrupt sources. It also includes a programmable serial UART interface, direct LED drive and output, an analog comparator, low power consumption idle mode, and a power-down feature.

The modulation process utilizes a CD40106 to buffer and amplify the digital signal carrier at 38KHz, which is then used to drive the infrared transmitting tube via a 8050 transistor, enabling the emission of infrared light. The transmission unit includes a keyboard matrix, code modulation, and an infrared sender. The 89C2051 chip modulates the key press signals onto the 38KHz carrier signal, which is amplified through a transistor before transmission. The infrared signal is encoded using a systematic code format, which includes a base-minus-one’s complement data code. The P1 port of the 89C2051 forms a matrix keyboard, generates timer interrupts with T1, and drives P3.3 to produce a rectangular wave at 38KHz, serving as the fundamental wave for infrared modulation.

The logic for the transmitted data is processed through P3.0 and subsequently enhanced by the 40106, which drives the infrared transmitting tube. The system enters a low power consumption mode after 10 seconds of inactivity, while pressing any key on the remote control interrupts this state, waking the CPU to resume normal operation. The specialized chip for the telecontrolled ejector can be categorized into two main classes based on the coding format. This design incorporates a relatively simple decoding scheme, exemplified by the uPD6121G from NEC, Japan, to form the transmitting circuit. Upon pressing a key on the projector, a unique remote control signal is transmitted, with variations in key presses corresponding to different coding schemes. This remote control signal exhibits characteristics such as pulse width modulation and serial encoding.The electric fan of remote control is to do a large amount of research and development and production in Pearl River Delta area of Guangdong in initial stage of the 1990s, and there is specialized mask chip that serves as top management chip, I have done the systematic scheme of receiving and emissive corollary use with the one-chip computer now. The infrared remote control circuit has already become the fashion of a kind of design circuit now, has introduced the outside line remote launch of Fructus Citri tangerinae, principle of the receiving system briefly now, provide an ingenious implement method that is used 89C2051 as the receiving system demoder of remote control, and 51 intact assembler codes. The main programs of schematic diagram and programming including being launched, received, calling order, receiving the procedure course of the procedure, regular interrupt program, thus finish this main point designed and consult the plot course of the procedure block-diagram, can write the application software.

The electric fan control system of remote control is divided into two major parts: Report controller and electric fan control panel, describe respectively as follows. In order to be able to be far away from the control electric fan of the distance, adopt the report controller outside Fructus Citri tangerinae.

Infrared report controller launch and the intersection of receiving and two part make up usually, radiating portion form by the intersection of one piece and the intersection of plane and 80C2051, etc. The receiving unit is formed by one-chip computer 89C51, etc. And MCS-8051 products compatibility, 2KB very heavy programming flash memory, survivability: 1000 is written / erased for cycle, 2.

7V and operated thed working range of 6V, the whole static behavior: 0Hz 24MHz, two-stage encrypts the programm store, 128* 8 internal RAMs, 15 programmable I/O lead wire, 6 interrupt sources, programmable serial UART passways, direct LED drive and output, analog comparator, low consumption idler and power down way on-chip 3 Modulate some: Adopt CD40106 to buffer and enlarge and have a facelift. The carriers of digital signal and 38K sent get along with, modulates it together, have a facelift and buffer and enlarge, is enlarged and driven the infrared transmitting tube by 8050, make it radiate infrared light.

1 The radiating portion includes keyboard matrix, code modulation, infrared sender. Use 89C2051 chip to modulate the key set signal in the carrier signal of 38KHz to amplify through the triode, transmit out. It is encoded into that infrared: Whole code =Guide yard systematic code systematic base-minus-one`s complement data code data base-minus-one`s complement.

P1 mouth of 89C2051 forms the matrix type keyboard, produces timer interrupt with T1, drive P3. 3 to produce the rectangular wave of one 38K, as the fundamental wave of ultrared modulation. Last logic what has been sent data and P3. 0 and after, it have a facelift 40106, being driven transmitting tubes infrared not to be launched triode. 3Enter alert status 10 seconds later when there is no key according to down time, prolong, the system is in the low power consumption mode.

When it is pushed that there are key sets, INT0 stops cutting off, wakes CPU up at the same time and carries on the working condition. The special purpose chip of the telecontrolled ejector is numerous, can be divided into two big classes according to the coded format, here we extensive in order to to use, decode relatively easy one, prove, uPD6121G of NEC, Japan of Israel, make up transmitting circuit, prove the code principle for example now.

After the key set of the projector is pushed, there is remote control yard that is sent out, keys pressed are different too in different remote control coding. This kind of remote control yard has the following characteristics: 1Adopt the intersection of pulse width and modulating serial yar