Transfer notes Doctor_A altar Friends!
Before making contact with a infrared remote control, free now want to use simple words to chat, here is the wrong place to welcome corrections that:
1: The concept of the infrared does not talk, it is a physical presence. The following 38K infrared transmitting and receiving chat, mainly about programmable IR codes.
2: infrared remote
infrared remote first need to send the "light" Infrared light emitting diode, and a light receiving "received tube" (that is not triggered by infrared tubes), as well as a signal source generating 38K (which may be MCU is interrupted realize there is a lot on the market infrared encoder IC), it requires only simple external circuit can be.
To the microcontroller, in order to increase the infrared LED current, you need a driver transistor. IC infrared code need only several peripheral circuits, the specifications are provided, not to mention here.
3: infrared receiver (where there do not understand can be found in the back of the answer you want, or continue "Baidu" "Google")
necessary can look at the details of the composition of the internal infrared receiver.
Receiving a first received level of the first divided pulse as well as the head.
Level type: 38K continuous reception signal may be output continuously low level, time can be infinite. The internal amplification and pulse shaping is directly coupled, it is possible to receive and output a continuous signal.
Pulse type: 38K can only receive intermittent signal, if the received 38K continuous signal, then after a few hundred ms will remain high unless very close (within twenty to thirty centimeters). The internal amplification and pulse shaping is capacitive coupling, it is not possible to receive and output a continuous signal.
Usually the remote control pulse type, only special occasions, such as serial modulated output, since the serial data may be continuously output 0, so the flat electricity.
4: Infrared remote control in the carrier in the end what is? (Do not affect your understanding of other carriers)
first-contact infrared I saw 'carrier' is a word I felt jerky. Lot of information online have a wide variety of drawing badly,
We start from the following points described, believe and so will understand:
(1) 38K how come?
Here talk given MCU, 38K pulse signal, the duty cycle (pulse of high value than the period is the duty cycle) to determine their own, since it is 38K, then the cycle of the pulse is 1/38000 S, remember this is not the length of time the high level, the length of time a pulse is one cycle, for example, we use a 38K interrupt pulses, the duty ratio is 1/2, the interruption time we will set 1/38000/2 S interrupted once, and then separated again by reversing the interrupt level once it forms a 1/2 frequency of a pulse duty ratio of 38K.
Also i! Here I would like to talk two errors encountered when learning IR:
First, when the first contact with infrared remote control, and the Internet to download a lot of information interruption time is actually 1 / 38000S, 19K pulse is generated signals, infrared certainly not to receive, not to talk about the coding. Most of the people but also the procedures are 19K. For people new to the dizzy flicker might have passed.
Second, it's time we use a single-chip microcontroller with query mode or interrupt mode problems.
We make use of interrupt, it can produce more accurate time reference at a clock faster conditions to produce a relatively correct pulse. The use of query, if the microcontroller 51, 12M crystal, using the 38K pulse to generate the query overflow, it made a big mistake, because of the way the use of queries from this action is not a waste of time or two machine cycle, it wasted a lot of time microcontroller error ridiculously large. If you tried to interrupt with success, you may wish to try the feeling of query failed.
Although the use of query programming is a lot simpler, but more large multi-error. I'm lazy committed an error.
5: What is the 38K IR carrier signal (in fact, I want to say into what is 38K coded signal (about Detailed))
(1) infrared remember 38K is not just only accept the 38K signal, it has a frequency offset (frequency deviation around fluctuations) range, but not remember range.
(2) said driver transistor, in fact as a switching transistor, the common emitter mode. So there are two ways off, using a PNP transistor it or NPN.
Generally, we use as a PNP switch, the use of a high level when the NPN is turned on, when the power of the microcontroller, the state of all of the IO port is high, this time the trigger switch, while we can be initialized when it shutdown, but even here can actually be a problem for future design of other things may be so committed a mistake should not have committed or manage a selection PNP.
(3) then we use "0" indicates infrared tube is turned on. . . . "1" denotes infrared tube ended
state drives the infrared light emission "IO" opening 38K is a trigger signal sent from the pulse signal to the IO port, a low-level pulse is turned on, a high level is ended. We will see that, if only a 38K, then the portion of the extract as previously mentioned, we will receive the signal at the receiving end of a low level.
Or we can understand it to be so: 38K infrared receiver only accepts signals (error range), we see a receiver transducer. Outputs a low level encountered 38K, 38K was not encountered on the pulled high.
So-called concept of "coding" than we have, we use have 38K 38K signal with no signal these two states, the use of infrared receiver to translate into a low level, a high level signal. . . . This is the most important thing.
When there is 38K. . When there is no 38K, we are all programmed to achieve. We now have the flexibility to manipulate not, some length of time is the length of time the low level of "recipient." The length of time the pulse is not the length of time the high level of the recipient. We only need to read the various combinations of high and low duration of the high and low on the receiving side to read the information provided by the transmitting side. This is called the "Agreement", the agreement is what we call good, you do so mean. The agreement made clear when what I what does it mean, you know the recipient. So there will be a variety of infrared coding, NEC / Philips IR codes are more common, and we can set our own coded according to their own needs. If you want to play with the remote control is no need to study people's infrared code protocols, own a few easy to program it. Think like NEC infrared protocol which comes to accept the head of a high level output of a few milliseconds low milliseconds is to represent "1", the high level milliseconds milliseconds is to represent the low level "0", the high level milliseconds low milliseconds is to represent the "boot code or user identification code", these are the people inside the NEC standard, we've set our own standards. I can say that the low 10ms 10ms allowed to accept on behalf of a high level, then the low 5ms 5ms another job on behalf of "1", the low 15ms 15ms after another job on behalf of "2", 25ms 25ms low another job representing a "0" of course this is only an analogy, because if the code length is too large to deal with other programs is not very flexible. Because we decoding is best not to be interrupted. Kind of like air-conditioning is rarely more than one hundred coding. less. As for the number of suitable, it considered appropriate. Encoded form also decide for themselves. Ever since, the above things and did not say "carrier" word, well below the carrier would talk about it. We "have 38K signal" in this state ( "Information") as a "1", the "signal is not the 38K" This state ( "Information") as "0", as in fact we want we can sent out 0 is the combination of the two states with 1. 1 and 0 with another meaning two states is 38K "you" with "No"
Thus 38K to bring the two information signals with a zero.
We'll 38K understood as a carrier signal, placing the signal this information, in fact, only 38K intermittent signal, if we say that the carrier is a carrier. But I prefer to call this signal as a kind of coded signal.
Well, to sum up. Infrared remote control is simple, there is no control MCU 38K infrared control signal is to use on-off signal to the microcontroller is sent to the MCU side having a length with no time to the receiver is translated into 38K has not been received with head combination calculated (decoded). Then execute the corresponding actions in accordance with the prior agreement of our code.
There is little need to add something.
That is, the first power receiver of
this very important, the receiver power supply The power supply like consistency decoded MCU, high and low output of such receiver can be compatible micro-IO identification. While a variety of receiver, some of circuit resources can not talk to 3V receiving pipe together with the MCU 5V, avoid waste. Some additional receiver intermediate supply pins is somewhat in the middle of the foot, the best time to see if the play Shunpian Mai to reserve a plurality lest they have burned after a trip.
As for learning infrared remote control, and some just need to learn coding, there is a need to study the carrier frequency. The latter is more get well. Welcome then paste ....
The following is an infrared transmitter, receiver (IR basics)
currently commercially available integrated infrared receiver, there are two: the level and type pulse type, the vast majority are impulse type, level type rarely.
Level-type, receiving 38K continuous signal may be output continuously low level, time can be infinite. The internal amplification and pulse shaping is directly coupled, it is possible to receive and output a continuous signal.
Impulse type, can only receive intermittent signals 38K, 38K continuous if the received signal, after a few hundred ms will remain high until very close (within twenty to thirty centimeters). The internal amplification and pulse shaping is capacitive coupling, it is not possible to receive and output a continuous signal. Usually the remote control pulse type, only special occasions, such as serial modulated output, since the serial data may be continuously output 0, so the flat electricity. 455K general remote controller 12 after frequency-divided output 37917HZ, referred to as 38K, 10 yards receiving bandwidth of 38 + -2K, 3 meters 35 ~ 42K. In the empty space is not reflected by the environment, it would be a distance of 10 meters or more relatively strong directivity. Indoors, if the wall is white, then in the space of 15 meters basic non-directional.
Receiver must filter, white light is filtered out. It can influence reception under the following environmental conditions, and even very serious:
1, direct light receiver, resulting in a saturated photodiodes. White light in the infrared component is also very strong.
2, there is a strong infrared heat source.
3, the strobe light, such as fluorescent lamps.
4, strong electromagnetic interference, such as fluorescent lamp is started, start the motor and the like.
38K signal is preferably 1/3 duty cycle, this is the most commonly used, according to the test 1/10 duty ratio and better sensitivity. The actual modulation time to less than 50%. The best intermittent.
Receiver type, as long as the level of the received infrared 38K continuously outputs a low level, with a very cool, before the old receiver is mostly of this type, but there is a fatal weakness: poor immunity short transmission distance (less than 1m).
The pulse type integrated infrared receiver must receive a certain frequency carriers have normal output baseband signals of the 38K, 38K-carrier transmission such as a 500HZ, a pulse-type integrated infrared receiver 500HZ square wave output, and if the transmitted carrier on successive 38K there will be a key moment followed by a low to a high level phenomenon. This pulse-type integrated infrared receiver overcomes the disadvantages of conventional level receiver type: relatively longer transmission distance, stability is greatly increased, stronger anti-interference. So it has completely replaced the old type acceptance level head, not in the electronics market, such as the owner explained to you absolutely impulsive.
You can view pictures when the phone is in the infrared emission control emission state
red storm problem
, some manufacturers can not produce the red storm infrared light as a technical problem to promote, as if violence is low-tech red, no red violence is high-tech. In fact, with or without red storm just a matter of choice, not a technical problem, 700nm wavelength than the light called infrared, 900nm infrared basically no more than the red violence, the shorter the wavelength, the stronger the red storm, the higher the degree of infrared sensors. Now the market has two main infrared light, one is a slight red storm, the wavelength of about 850nm, red one is no violence, the wavelength of about 940nm. With a camera, the sensitivity wavelength of 850nm, 940nm wavelength than the sensitivity to 10 times better. So this has a slight red 850nm infrared light bursts have higher efficiency, preference should as infrared night vision surveillance.
It makes sense to say it?
Red storm is a description of the infrared light operating conditions. Working lights at work, if there is red storm will die red dots appear. If no red violence, then, does not work and the work of human eyes. No red dot
850nm and 940nm are red burst, but a little less than 940
common infrared emission wavelength of 940nm and has two kinds of wavelengths 850nm, 940nm wavelength infrared emission control is mainly used for modulation coding and signal transmission, and 850nm wavelength the security and other infrared light source, there is mainly used for receiving tube 850nm ~ 950nm generic model. The difference between the tube and the tube 850 940 is that the size of their power. 850 belongs to the high-power, which is characterized by: transmitting a short-range, high sensitivity, suitable for imaging monitoring piece. 940 belongs to the low-power, which is characterized by: transmitting distance, low sensitivity, is mainly used on the remote control
to select a launch tube 850
General machine design short distance, generally applicable to a large angle IR emission tube, 45, 60, the most versatile on the market angle, general wafer Alternatively, the best choice with 12Pcs, 14Pcs Japan and Taiwan, the market, 18Pcs, 24Pcs launch tube machine, such products generally used in the development of a distance of 5-20 meters, over 20 meters when the developing machine, it is necessary recommended in Japan and Taiwan wafer, such as 28Pcs, 36Pcs, 48Pcs, 64Pcs products, At the same time need to use a smaller angle would be better.
If you modulated waveform is active high, 38KHz receiver output must be low; the output signal of almost all of the infrared receiver is inverted.
Receiver generally have a good variety, a long time is how to tell a tripod arrangement?
Before making contact with a infrared remote control, free now want to use simple words to chat, here is the wrong place to welcome corrections that:
1: The concept of the infrared does not talk, it is a physical presence. The following 38K infrared transmitting and receiving chat, mainly about programmable IR codes.
2: infrared remote
infrared remote first need to send the "light" Infrared light emitting diode, and a light receiving "received tube" (that is not triggered by infrared tubes), as well as a signal source generating 38K (which may be MCU is interrupted realize there is a lot on the market infrared encoder IC), it requires only simple external circuit can be.
To the microcontroller, in order to increase the infrared LED current, you need a driver transistor. IC infrared code need only several peripheral circuits, the specifications are provided, not to mention here.
3: infrared receiver (where there do not understand can be found in the back of the answer you want, or continue "Baidu" "Google")
necessary can look at the details of the composition of the internal infrared receiver.
Receiving a first received level of the first divided pulse as well as the head.
Level type: 38K continuous reception signal may be output continuously low level, time can be infinite. The internal amplification and pulse shaping is directly coupled, it is possible to receive and output a continuous signal.
Pulse type: 38K can only receive intermittent signal, if the received 38K continuous signal, then after a few hundred ms will remain high unless very close (within twenty to thirty centimeters). The internal amplification and pulse shaping is capacitive coupling, it is not possible to receive and output a continuous signal.
Usually the remote control pulse type, only special occasions, such as serial modulated output, since the serial data may be continuously output 0, so the flat electricity.
4: Infrared remote control in the carrier in the end what is? (Do not affect your understanding of other carriers)
first-contact infrared I saw 'carrier' is a word I felt jerky. Lot of information online have a wide variety of drawing badly,
We start from the following points described, believe and so will understand:
(1) 38K how come?
Here talk given MCU, 38K pulse signal, the duty cycle (pulse of high value than the period is the duty cycle) to determine their own, since it is 38K, then the cycle of the pulse is 1/38000 S, remember this is not the length of time the high level, the length of time a pulse is one cycle, for example, we use a 38K interrupt pulses, the duty ratio is 1/2, the interruption time we will set 1/38000/2 S interrupted once, and then separated again by reversing the interrupt level once it forms a 1/2 frequency of a pulse duty ratio of 38K.
Also i! Here I would like to talk two errors encountered when learning IR:
First, when the first contact with infrared remote control, and the Internet to download a lot of information interruption time is actually 1 / 38000S, 19K pulse is generated signals, infrared certainly not to receive, not to talk about the coding. Most of the people but also the procedures are 19K. For people new to the dizzy flicker might have passed.
Second, it's time we use a single-chip microcontroller with query mode or interrupt mode problems.
We make use of interrupt, it can produce more accurate time reference at a clock faster conditions to produce a relatively correct pulse. The use of query, if the microcontroller 51, 12M crystal, using the 38K pulse to generate the query overflow, it made a big mistake, because of the way the use of queries from this action is not a waste of time or two machine cycle, it wasted a lot of time microcontroller error ridiculously large. If you tried to interrupt with success, you may wish to try the feeling of query failed.
Although the use of query programming is a lot simpler, but more large multi-error. I'm lazy committed an error.
5: What is the 38K IR carrier signal (in fact, I want to say into what is 38K coded signal (about Detailed))
(1) infrared remember 38K is not just only accept the 38K signal, it has a frequency offset (frequency deviation around fluctuations) range, but not remember range.
(2) said driver transistor, in fact as a switching transistor, the common emitter mode. So there are two ways off, using a PNP transistor it or NPN.
Generally, we use as a PNP switch, the use of a high level when the NPN is turned on, when the power of the microcontroller, the state of all of the IO port is high, this time the trigger switch, while we can be initialized when it shutdown, but even here can actually be a problem for future design of other things may be so committed a mistake should not have committed or manage a selection PNP.
(3) then we use "0" indicates infrared tube is turned on. . . . "1" denotes infrared tube ended
state drives the infrared light emission "IO" opening 38K is a trigger signal sent from the pulse signal to the IO port, a low-level pulse is turned on, a high level is ended. We will see that, if only a 38K, then the portion of the extract as previously mentioned, we will receive the signal at the receiving end of a low level.
Or we can understand it to be so: 38K infrared receiver only accepts signals (error range), we see a receiver transducer. Outputs a low level encountered 38K, 38K was not encountered on the pulled high.
So-called concept of "coding" than we have, we use have 38K 38K signal with no signal these two states, the use of infrared receiver to translate into a low level, a high level signal. . . . This is the most important thing.
When there is 38K. . When there is no 38K, we are all programmed to achieve. We now have the flexibility to manipulate not, some length of time is the length of time the low level of "recipient." The length of time the pulse is not the length of time the high level of the recipient. We only need to read the various combinations of high and low duration of the high and low on the receiving side to read the information provided by the transmitting side. This is called the "Agreement", the agreement is what we call good, you do so mean. The agreement made clear when what I what does it mean, you know the recipient. So there will be a variety of infrared coding, NEC / Philips IR codes are more common, and we can set our own coded according to their own needs. If you want to play with the remote control is no need to study people's infrared code protocols, own a few easy to program it. Think like NEC infrared protocol which comes to accept the head of a high level output of a few milliseconds low milliseconds is to represent "1", the high level milliseconds milliseconds is to represent the low level "0", the high level milliseconds low milliseconds is to represent the "boot code or user identification code", these are the people inside the NEC standard, we've set our own standards. I can say that the low 10ms 10ms allowed to accept on behalf of a high level, then the low 5ms 5ms another job on behalf of "1", the low 15ms 15ms after another job on behalf of "2", 25ms 25ms low another job representing a "0" of course this is only an analogy, because if the code length is too large to deal with other programs is not very flexible. Because we decoding is best not to be interrupted. Kind of like air-conditioning is rarely more than one hundred coding. less. As for the number of suitable, it considered appropriate. Encoded form also decide for themselves. Ever since, the above things and did not say "carrier" word, well below the carrier would talk about it. We "have 38K signal" in this state ( "Information") as a "1", the "signal is not the 38K" This state ( "Information") as "0", as in fact we want we can sent out 0 is the combination of the two states with 1. 1 and 0 with another meaning two states is 38K "you" with "No"
Thus 38K to bring the two information signals with a zero.
We'll 38K understood as a carrier signal, placing the signal this information, in fact, only 38K intermittent signal, if we say that the carrier is a carrier. But I prefer to call this signal as a kind of coded signal.
Well, to sum up. Infrared remote control is simple, there is no control MCU 38K infrared control signal is to use on-off signal to the microcontroller is sent to the MCU side having a length with no time to the receiver is translated into 38K has not been received with head combination calculated (decoded). Then execute the corresponding actions in accordance with the prior agreement of our code.
There is little need to add something.
That is, the first power receiver of
this very important, the receiver power supply The power supply like consistency decoded MCU, high and low output of such receiver can be compatible micro-IO identification. While a variety of receiver, some of circuit resources can not talk to 3V receiving pipe together with the MCU 5V, avoid waste. Some additional receiver intermediate supply pins is somewhat in the middle of the foot, the best time to see if the play Shunpian Mai to reserve a plurality lest they have burned after a trip.
As for learning infrared remote control, and some just need to learn coding, there is a need to study the carrier frequency. The latter is more get well. Welcome then paste ....
The following is an infrared transmitter, receiver (IR basics)
currently commercially available integrated infrared receiver, there are two: the level and type pulse type, the vast majority are impulse type, level type rarely.
Level-type, receiving 38K continuous signal may be output continuously low level, time can be infinite. The internal amplification and pulse shaping is directly coupled, it is possible to receive and output a continuous signal.
Impulse type, can only receive intermittent signals 38K, 38K continuous if the received signal, after a few hundred ms will remain high until very close (within twenty to thirty centimeters). The internal amplification and pulse shaping is capacitive coupling, it is not possible to receive and output a continuous signal. Usually the remote control pulse type, only special occasions, such as serial modulated output, since the serial data may be continuously output 0, so the flat electricity. 455K general remote controller 12 after frequency-divided output 37917HZ, referred to as 38K, 10 yards receiving bandwidth of 38 + -2K, 3 meters 35 ~ 42K. In the empty space is not reflected by the environment, it would be a distance of 10 meters or more relatively strong directivity. Indoors, if the wall is white, then in the space of 15 meters basic non-directional.
Receiver must filter, white light is filtered out. It can influence reception under the following environmental conditions, and even very serious:
1, direct light receiver, resulting in a saturated photodiodes. White light in the infrared component is also very strong.
2, there is a strong infrared heat source.
3, the strobe light, such as fluorescent lamps.
4, strong electromagnetic interference, such as fluorescent lamp is started, start the motor and the like.
38K signal is preferably 1/3 duty cycle, this is the most commonly used, according to the test 1/10 duty ratio and better sensitivity. The actual modulation time to less than 50%. The best intermittent.
Receiver type, as long as the level of the received infrared 38K continuously outputs a low level, with a very cool, before the old receiver is mostly of this type, but there is a fatal weakness: poor immunity short transmission distance (less than 1m).
The pulse type integrated infrared receiver must receive a certain frequency carriers have normal output baseband signals of the 38K, 38K-carrier transmission such as a 500HZ, a pulse-type integrated infrared receiver 500HZ square wave output, and if the transmitted carrier on successive 38K there will be a key moment followed by a low to a high level phenomenon. This pulse-type integrated infrared receiver overcomes the disadvantages of conventional level receiver type: relatively longer transmission distance, stability is greatly increased, stronger anti-interference. So it has completely replaced the old type acceptance level head, not in the electronics market, such as the owner explained to you absolutely impulsive.
You can view pictures when the phone is in the infrared emission control emission state
red storm problem
, some manufacturers can not produce the red storm infrared light as a technical problem to promote, as if violence is low-tech red, no red violence is high-tech. In fact, with or without red storm just a matter of choice, not a technical problem, 700nm wavelength than the light called infrared, 900nm infrared basically no more than the red violence, the shorter the wavelength, the stronger the red storm, the higher the degree of infrared sensors. Now the market has two main infrared light, one is a slight red storm, the wavelength of about 850nm, red one is no violence, the wavelength of about 940nm. With a camera, the sensitivity wavelength of 850nm, 940nm wavelength than the sensitivity to 10 times better. So this has a slight red 850nm infrared light bursts have higher efficiency, preference should as infrared night vision surveillance.
It makes sense to say it?
Red storm is a description of the infrared light operating conditions. Working lights at work, if there is red storm will die red dots appear. If no red violence, then, does not work and the work of human eyes. No red dot
850nm and 940nm are red burst, but a little less than 940
common infrared emission wavelength of 940nm and has two kinds of wavelengths 850nm, 940nm wavelength infrared emission control is mainly used for modulation coding and signal transmission, and 850nm wavelength the security and other infrared light source, there is mainly used for receiving tube 850nm ~ 950nm generic model. The difference between the tube and the tube 850 940 is that the size of their power. 850 belongs to the high-power, which is characterized by: transmitting a short-range, high sensitivity, suitable for imaging monitoring piece. 940 belongs to the low-power, which is characterized by: transmitting distance, low sensitivity, is mainly used on the remote control
to select a launch tube 850
General machine design short distance, generally applicable to a large angle IR emission tube, 45, 60, the most versatile on the market angle, general wafer Alternatively, the best choice with 12Pcs, 14Pcs Japan and Taiwan, the market, 18Pcs, 24Pcs launch tube machine, such products generally used in the development of a distance of 5-20 meters, over 20 meters when the developing machine, it is necessary recommended in Japan and Taiwan wafer, such as 28Pcs, 36Pcs, 48Pcs, 64Pcs products, At the same time need to use a smaller angle would be better.
If you modulated waveform is active high, 38KHz receiver output must be low; the output signal of almost all of the infrared receiver is inverted.
Receiver generally have a good variety, a long time is how to tell a tripod arrangement?
Respectively by mechanical methods which measure the resistance of the two legs, the legs to find the minimum value of one wherein the bars do not move at this time table, the answer out: the red bar is connected to Vcc, black bar table is a ground contact Oh do not say another foot is the signal pin (IR) up.
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