FI111668B - Transmission method for an infrared remote control system - Google Patents

Abstract

To transmit, from a transmitter to a receiver, signals triggered by prolonged depression of a button, the invention calls for repeat signals (R) to be transmitted while the button is kept depressed. Releasing the button triggers a separate switch signal (S). A burst/pause modulation technique is used to transmit the repeat and switch signals (R and S), the information units being defined by different burst-separation lengths. The burst separations and burst packets are chosen such that IR transmitters with only limited power supplies can be used.

Description

111668

Transmission method for infrared remote control system. Överföringsförfarande för ett infraräd-fjärrstyrningssystem

The present invention relates to a method of transferring an infrared remote control system for transmitting data strings or messages between a transmitter and a receiver, which is triggered by long and short keystrokes on a keyboard, the various keystrokes being interpreted by the receiver.

10 Seemingly continuous processes, such as sequentially traversing a sequence of discrete setpoints, are usually controlled by keystroke, for example, remotely moving the command for each step, or moving a few commands, whereby the omission of the command within a predetermined time is interpreted as start and end keystrokes.

For transferring binary coded data groups or data strings, i.e., data represented by on or off states, so-called transfer protocols are used. Then, a station transmits such data queues, for example, by means of 20 high frequency waves, and the receiving station interprets the received data queues for which it must be aware of a transmission protocol. This defines the form and content of the data transmitted from the essential parts and thus only renders it interpretable.

A number of such protocols are known and are used throughout the data transmission domain. The large number of different protocols is mainly explained by many different purposes of use, such as data transfer of computer information or transmission of pure control data for instruments. In particular, data security, integrity and transfer rate are also decisive factors which, in part, adversely affect each other.

30 The means of transmission must also be taken into account.

2 111668

The object of the invention is to find a transfer method which, with the smallest possible set of instructions, ensures a reliable transmission of a long keystroke, whereby the end of the keystroke must be identified as precisely as possible and which requires only a limited amount of energy.

This problem is solved by repeatedly transmitting a repetition signal R from the time Td is pressed from the time TE is released from the transmitter, so long as the key is released immediately generates the shift signal S and the repetition signal 10R ends, after the key has been pressed, only the exchange signal S is transmitted, whereupon this exchange signal S is transmitted immediately after the key is released, and a burst-pause modulation scheme is provided for transmitting the repetition and switching signals R and S, with burst periods of each burst the number and burst intervals TAO, OR, ... are selected such that during the breaks, despite the low voltage and capacity power source, the energy and voltage amplitude required for transmission is generated.

A preferred embodiment of the invention is characterized in that a circuit 20 is provided which in the receiving device does not interpret the absence of a repeat command to terminate a key press, but merely a break.

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Another preferred embodiment of the invention is characterized in that the first repetition signal is transmitted when the key is pressed for more than 400 ms and repeated at intervals of up to 1 second until the key is released.

A particular, preferred embodiment of the invention is characterized in that the receiver is provided with a circuit which generates a plurality of discrete control signals 30 after receiving the repetition signal, at least between the repetition signals.

3, 111668

By means of the transfer method according to the invention, it is possible to reliably control seemingly continuous processes by long pressing of the transmitter, for example for several seconds. When the playback signal is interrupted, the process is not terminated but merely interrupted and may continue when the playback signal is re-received. Thus, in the light control device, for example, due to the interruption of the transmission signal due to transient obstruction of the transceiver connection, the dimming operation which is initiated and continued by long pressing of the key is not stopped, but only interrupted. As soon as other playback signals are received, the dimmer operation continues in the original direction. When the key is released, a change signal is sent as a separate command for the light control. This shift signal indicates the end of a process that is currently in progress, for example, the described dimming operation. Thus, for example, the direction of the dimmer operation can be reversed, and the next received repetition signals produce a dimming effect opposite to the original direction. In preferred embodiments of the invention, it is arranged that 16 bursts are used per burst packet and that the break length is at least 10 times the length of the burst packet. In another preferred embodiment, four different information units having 20 different burst intervals are followed, each information unit being used to indicate the beginning or end of a data string and to indicate states 0 and 1, respectively.

With the method of the invention, reliable transmission of messages or data queues is also possible with transmitters having a weak power source. The transmitter can now refresh its energy storage during burst intervals to transmit the next burst packet with sufficient power. The energy reserve »thus no longer needs to be dimensioned so as to guarantee uninterrupted transmission power. The smaller-sized energy stores are also considerably smaller in size and weight than the large energy stores, which in particular in the hand transmitter means smaller dimensions and lower weight and thus greater comfort.

An embodiment of the invention will now be described in more detail with reference to the drawing 5. In the drawing: Fig. 1 shows a block diagram of a transmitter according to the invention; Figure 2 shows the entire address space of the transmitter; Figure 3 shows the message structure of the message to be transferred; Figure 4 shows a circuit diagram of a transmitter power supply; Figures 5 and 6 show the PPM encoding and the transmitter modulated PPM signal; Fig. 7 is a block diagram of a receiver according to the invention; Fig. 8 is a block diagram of a preamble; Fig. 9 shows a signal transmission diagram as a function of a long keystroke and corresponding light control; Fig. 10 shows a signal transfer diagram as a function of short key press 25 and corresponding on / off control.

Fig. 1 is a block diagram of transmitter 10. The transmitter 10 is, for example, an infrared transmitter for controlling the blinds of various electrical devices such as luminaires, audio devices. The transmitter 10 comprises a keypad 12, a first microprocessor 30 or an ASIC 14, a power supply 16, an address selector 18, and a transmitter stage 20.

111668 By pressing any key on the keypad 12, the power supply 16 is activated by the first control signal S1 of the keypad 12 and generates a supply voltage VS. for the microprocessor or ASIC 14 and the transmit diode S2 of the transmitter stage 20. As soon as the power supply 16 has reached the required voltage, the microprocessor or ASIC circuit 14 starts and takes the power supply 16 into control by means of a second control signal S2. The output signal T5 of the keypad 12 is read by a microprocessor or an ASIC 14 and indicates which key of the keypad 12 has been pressed.

10 The first control signal S1 and the second control signal S2 are connected to a logic OR circuit 19 formed by the third control signal S3 which activates the power supply 16.

The microprocessor or ASIC circuit 14 then generates a fourth address control signal 15 S4, which in the address selector 18 by means of the logic circuit 21 selects the device addresses A1, A2, A3, A4, ... set by the code switch 22.

The addresses are given, for example, by eight address bits, whereby the address space (see Fig. 2) is logically divided into four blocks (2 bits) each containing 20 groups of 8 bits (3 bits), each having eight hardware addresses (3 bits).

• * The transmitter 10 has a group address G, each set by a code switch 22, and within this group four device addresses can be freely selected.

25 The block address is permanently wired. The transmission of instructions between the transmitter 10 and the receiver of the control device is based on single data queues or messages (one instruction is transmitted per message), whereby the information is digitally encoded.

6, 111668

The message structure of the message is shown in Figure 3. The message has: - eight address bits - four data bits r - four data backup bits (CRC encoding) 5 - start bit SOT (Start of Telegram) - end bit EOT (End of Telegram).

The start bit SOT and the stop bit EOT are used for synchronization so that the beginning or end of the message is uniquely identified.

Each of the keys of the keyboard 12 is associated with exactly one of these device addresses. The hardware address indicated by the output signal A5 of logic circuit 21 determines the three least significant bits of the message address field (Fig. 3). At the same time, the group address G set by the code switch 22 is determined which determines the three most significant address bits of the message. The two most significant 15 bits of the address field are filled with corresponding block addresses.

Depending on the length of the keystroke 12 of the keypad, four data bits are used to represent the corresponding instructions. The other bits for data validation (CRC coding) 20 are added to the address and data field thus formed, and thus the message (Fig. 3) is formed.

Microprocessor 14 performs burst-gap modulation (Pulse Position Modulation and subsequent carrier modulation) and generates a transmitter control signal TM to control transmitter 24 connected in series with transmit diode D2. This transceiver 24 generates a transmit current IS through diode D2 which in response corresponds to generate light signals in the infrared region. Since the power source is not able to supply enough energy to generate the transmit current IS, a capacitor C1 is dimensioned for intermediate storage of energy so that the entire message can be transmitted at a minimum current IS.

7, 111668

As soon as no further messages are sent based on the key press (key released), the microprocessor or the ASIC circuit 14 switches off the power supply 16 with the second control signal S2, whereby the power consumption in standby mode can be reduced to a very small value.

5

The circuit of the power supply 16 is shown in Figure 4.

Only one battery 26 with a low voltage (1.5 V cell) is used to power the transmitter 10. However, a higher voltage is required for controlling the infrared transmission diode D2 and the microprocessor 10 or the ASIC circuit 14. This is accomplished by connecting in series with the battery 26 a magnetic dc / dc converter 28 which converts a small supply voltage VB to a higher voltage level VS. Through the input 30 of the third control signal S3, a control circuit 32 is activated, by which the transistor T1 is switched on and a current IL starts to flow through the coil L15. The coil L stores an amount of energy proportional to the current. If the transistor T1 is now switched non-conductive, the coil accumulates energy which flows through diode D4 to capacitor C1, whereby voltage begins to form across capacitor C1. By repeatedly turning the transistor T1 on and off, energy packets are transferred to capacitor C1, whereby voltage 20 gradually increases. This is continued until the desired voltage VS. is generated across capacitor C1. The control circuit 32 detects the achievement of the desired voltage and interrupts the periodic switching on and off of the transistor T1, and in particular, until the control voltage UR drops below a predetermined value. The periodic switching on and off is achieved by an oscillator, whereby the coil L can be used as a frequency forming component. The oscillator is built into the control circuit 32.

When the infrared transmitter 10 is activated, the voltage converter 28 is activated.

The voltage of the battery 26 is thus converted to the desired higher voltage level VS, and is preferably stored in capacitor C1 as an energy store. After a specified period of time, the message to be transmitted is transmitted by the wired transmitter 24 and the infrared diode D2, whereupon the capacitor C1 is again partially discharged. This can be achieved, for example, by using a 1.5 V cell as an energy source. Thus, the IR transmitters 10 may be constructed smaller than hitherto, or provide more space for transmission electronics. There are also fewer replaceable batteries.

The message transfer method is schematically illustrated in Figures 5, 6.

10 Transmitter 10 now has a limited source of power (1.5V battery; Type AAA), which requires the transmission method to be selected so that the battery 26 can meet the required range (approx. 20m) and lifetime (approx. 3 years under normal operating conditions). .

15 The message is transmitted by burst-break modulation method. For this transfer, the individual bits are encoded in the microprocessor 14 by the Pulse Position Modulation (PPM) method and then modulated by a carrier. In this coding, the information is included in the distance between two pulses (TAO, OR in Figure 5).

20

In total, four different distances are used: EOT, "0", "1" and SOT. Because the unmodulated PPM method is broadband, individual pulses are modulated on a carrier (447.5 kHz), and in particular by transmitting 16 cycles per pulse. Such a pulse packet is called a burst having a burst length TB (32 [mu]). The modulated PPM signal (Figure 6) is called the BPM signal (Burst Position Modulation). This coding and modulation method is very energy efficient since energy is consumed only during burst phases and the distances between bursts (TAO, TB, OR, TB, etc.) can be used to at least partially charge the temporary energy storage, especially when burst intervals are much larger than burst lengths.

9111668

End bit EOT: 14 * TB

Bit 0: 19 * TB

Bit 1: 24 * TB

Start bit SOT: 29 * TB.

, 5

For example, a burst packet having a length of TB has 16 periods, i.e., the IR transmission diode D2 emits 16 short light flashes. After a time interval of TAO, another burst packet is retransmitted. Burst intervals TAO, OR are selected such that transmitter 10 has sufficient time, namely, 10 TAO - TB, to transmit the remaining burst packet to generate the remaining energy unless it has a constant energy reserve. Thus, a transmitting device with a weak energy source can be used to transmit such infrared signals, because it does not continuously transmit a weak signal, but only a burst of a stronger signal, limited in time. Thus, in particular, the dimensions and weight of the transmitting device can be reduced, since the energy source usually forms the heaviest and most inflexible element of hand transmitters in particular.

The receiver 36 (Fig. 7) thus interprets the burst intervals between the received burst bursts 20, recognizes the different messages, and, according to said coding, passes it further to the interpretation circuit 38.

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The receiver 36 comprises a receiving diode D1, which converts the infrared signals into a current, a preamplifier 40 which processes the received weak current signals 25 so that they can be further processed by the second microprocessor 42 of the subsequent interpretation circuit 38.

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At the receiver 36, the infrared signal (light burst packet) is converted by a receiving diode D1 to a current burst. To filter this current burst 30, a bandpass filter 44 (Fig. 8) can be used which is capable of sufficiently attenuating any interference outside the carrier frequency but which nevertheless passes the bursts. Most infrared interference frequencies are in the frequency range of about 40 kHz (e.g., pre-switching devices, etc.). The preamplifier 40 (FIG. 8) is designed such that the received signals are first filtered and then amplified. After amplification, the number of cycles of the received signal is calculated by pulse counter 46, and if the required number of pulses is received, a single receiving pulse S5 is output to another microprocessor or ASIC circuit 42, which then interprets the distances between these pulses.

In addition, the receiver 36 interpreter circuit 38 includes two code switches 48 for determining the device address AI (3 least significant bits). The second microprocessor 42 reads these addresses when receiving the instruction message and compares the address field with the address set in the receiver 36. If the addresses are the same, the instruction is stored for further processing, otherwise it is rejected.

At the same time, the data backup bit is used to examine the instruction message for a possible transmission error. The received message is rejected if it is found to be incomplete.

The interpreter circuit 38 further includes a memory 50 (RAM / EEPROM) for storing status information 20 for controlling the control unit 52. Through the so-called Mode inputs, the microprocessor 42 is informed of the type of control unit 52 to be controlled, whereby it calls the corresponding program from the program memory 54 (ROM). Thus, a single microprocessor 42 can generate a plurality of different control signals S6 for different control units 52 (e.g., a phase-25 switch, a relay, etc.), and particularly depending on the Mode inputs.

Fig. 9 shows a diagram of transmitting a long keypress of a transmitter via infrared transmission of messages, using a limited power source in the transmitter to control continuous and seemingly continuous processes with only one key.

The 12 keys (e.g., T1) of the keypad of the transmitter 10 are pressed at TD and subsequently released again at TE, as shown in FIG. 9 in the upper diagram.

5 If the keystroke lasts longer than TW (TW is 400 ms), the keystroke is interpreted as "long" and from this moment (from the first microprocessor 42), repetition signals R (or HOLD commands) are transmitted until the key is released at TE. In this connection, an exchange signal S (or a TOGGLE command) is transmitted from microprocessor 42, and transmission of the repetition signals R 10 stops. At the same time, releasing the key causes the steering direction to change direction. For example, longer key presses may be used to control a seemingly continuous process such that the output control signal S7 of the control unit 52 of the receiver 36 is changed by a small amount AS in short periods ΔΤ, such as to dim the lights.

Due to the limited power source (battery) in transmitter 10, the repetition signal distances TR need to be selected sufficiently large (low power consumption and thus longer battery life), and on the other hand the end of keystroke on receiver 36 must be identified as accurately as possible. . To this end, when the key is released, a change signal S is transmitted, and the receiver 36 interprets this to terminate the key press. Thus, the distance TR between the repeat commands can be set to a large (800 ms). The time steps ΔΤ for the control variables are small (about 60 ms) compared to the distance 25 of the repetition commands R, and yet the final value can be set accurately, since the shift signal is immediately sent when the key is released.

The error in transmitting the repetition signal R at the receiver 36 is not interpreted as a stop of the key press 30, which would also result in a change of direction, but is interpreted as an interruption whereby the period TT until the interruption is detected is 12111668 longer than the distance TR When such a break is detected at TU, the control signal S7 is no longer changed until a repeat signal R is received again, and in this case no change in direction is detected. The absence of a stop switch signal S is interpreted as a break, i.e. a subsequent long key press on the transmitter 10 is interpreted in the receiver 36 to resume the original key press.

Fig. 10 shows a transmission transmission chart for a short key press of less than 400 ms. A switching signal S is transmitted from the microprocessor or the ASIC circuit 14 10, which in the receiver performs either an on or off (EIN / AUS) depending on whether the current state was off (AUS) or on (EIN).

The HALTEN function is used to establish a logical connection between the transmitter 15 10 and the receiver 36 and serves for long keystroke (> 400 ms) transmission.

A short key press produces a change signal S or a switch message, a long key press produces a repetition signal R or a repeat word 20 man followed by a switch message S when the key is released.

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Claims (5)

13 111668 A method of transmitting an infrared remote control system for transmitting data strings or messages between a transmitter (10) and a receiver (36), each transmission being triggered by keystrokes on the keyboard (12), the various keystrokes on the keyboard (12) being interpreted by a receiver from the down time (TD) to its down time (TE), a repetition signal (R) is repeatedly transmitted from the transmitter (10), as long as the key is pressed for a minimum time (TW), immediately releasing the key generates transmission of the shift signal (S) and repetition signal (R). ends by holding down a short, non-TW key, only the shift signal (S) is transmitted, whereupon this shift signal (S) is transmitted immediately after the key is released, and that for repetition and switch signals (R) and (S) to the transmitter ( 10) has been arranged 15th burst-pause modulation method, wherein the number of burst cycles and burst intervals TAO, OR, ... of each burst packet of length TB are selected such that during the breaks, despite the low voltage and capacity power supply (26), the energy and voltage amplitude required for transmission is generated. 20 A transmission method according to claim 1, characterized in that there is an ♦ <: arranged circuit which in the receiver (36) interprets not the end of a key press but merely the interruption of the absence of a repetition signal (R) transmitted after more than 400 ms. every 1 s until the key is released. > • · Transmission method according to claim 1, characterized in that 16 cycles are used per burst packet, whereby four different information units having four different burst intervals are needed, so that 30 information units at each start and end of 14111668 and states 0 and 1 are respectively available. and that the burst interval is at least 10 times the burst packet length. Transmission method according to claim 1, characterized in that the voltage converter necessary for generating the transmission energy is a magnetic converter to which a capacitor (C1) is connected for the intermediate storage of energy. Transmission method according to claim 1, characterized in that after receiving the repeat signal (R), the receiver (36) generates a plurality of discrete control signals (S7) at least between the repeat signals. * · * • «15 111668 1. Överföringsförfarande för ett infrarött-fjärrstyrningssystem för överföring av data sequencer eller telegram mellan en sändare (10) och en mottagare 5 (36), flowing Överföring ut medsapps (12), knapp knapptryckningarna pä knappsatsen (12) tolkas med mottaga-ren, kännetecknat av, att det fränididpointten (TD) for nedtryckning av en knapp account tidpunkten (Te) for dess släppande av knappen upprepat sänds en upprepningssignaler (R) frän sän your account vida att knappen ned-10 trycks en minimitid (TW), varvid släppandet av knappen genast genererar en växlingssignal (S) och sedandet av upprepningssignalen (R) avslutas, att det genom att en kort, tiden TW icke-överskridande tid ned-tryckt about the band Växlingssignalerna (S), the colors denna växlingssignal (S) geneva sänds efter släppande av knappen, och att det för överföring av upprep-15 nings- och växlingssignalerna ( R) och (S) anordnats et skur-pause-modu-lationsförfarande i sändaren (10), color skurperiodernas antal i shade skur-packet med längden TB och skurmellanrummen TAO, THAI, ... express, att det under pauserna, trots en strömkälla (26) med læg spänning och capacity, bildas den Energi och spänningsamplitud som behövs för överföringen. 20 2. Överföringsförfarande enligt patentkrav 1, kännetecknat av att det an- «? ordnats en krets, som i mottagaren (36) vid avsaknad av en upprepningssig- nal (R), wobble sänds efter en knapptryckning länre än 400 ms och upprepas med interval av högst 1 s tills knappen släpps, inte tolkar detta säsom 25 knapptry sorry to avbrott. . * 3. Överföringsförfarande enligt patentkrav 1, kännetecknat av att det används 16 perioder per skurpaket, varvid man behöver ha account förfogande fyra olika informationsenheter med fyra olika skuravständ för att shadow informa-30 tionsenhet skall beteckna dataektens 111668 ställa tillständen O och 1, och att skuravständen är minst 10 gänger skurpa-ketets längd. 4. Överföringsförfarande enligt patentkrav 1, kännetecknat av att den för 5 genereringen av överföringsenergin uvändän späningsomvandlaren en magnetisk omvandlare, som kopplats account en capacitor (Cl) for mellanlag-ring av Energin. 5. Överföringsförfarande enligt patentkrav 1, kännetecknat av att mottaga-10 ren (36) efter mottagande av en upprepningssignal (R7) generator et antal discret styrsignaler (S7) ätminstone under upprepningssignalernas tidsinter-Vall. * · 1 of ·