Reference / Paper · 2024
Vishay Data Formats for IR Remote Control (doc 80071, Rev 2.3)
Remote-control carrier frequencies and burst timing: what an IR light-gun sensor must coexist with.
- ir remote
- carrier
- burst
- nec
- rc5
Reference / Paper · 2024
Remote-control carrier frequencies and burst timing: what an IR light-gun sensor must coexist with.
Data Formats www.vishay.com Vishay Semiconductors Data Formats for IR Remote Control Several methods of modulation have become well established. A reliable and power saving transmission method in which bursts of the carrier frequency are transmitted is called “Pulse Code Modulation” (PCM). There are three commonly used representations of one bit in remote control systems which are described in the following diagrams. In most remote control transmission systems, only small data rates are required for transmitting the control functions of home entertainment equipment. The reliability of the transmission is essential as an incorrect interpretation of a transmitted code is not permissible. Corrupted signals must be ignored. In most coding schemes, commands are repeated until the remote controlled device reacts as desired. The operator can directly observe the result of pressing a key by means of visual feedback. The “Bi Phase Coding” has one rising or falling edge in the center of each time slot (Fig. 1). In the “Pulse Distance Coding”, all bursts have the same length but the time between the bursts is different depending on the value of the bit (Fig. 2). In the “Pulse Length Code”, there are two kinds of burst lengths depending on the bit value (Fig. 3). Because IR signals are confined within a room and because there is only a short period of data transmission with each key press, there are no legal restrictions for IR transmission in the frequency band between 30 kHz and 56 kHz. "1" "1" "0" "0" "0" "0" "1" "1" 17049 Fig. 1 - BI Phase Coding (a rising edge within a time window is equivalent to a “1“, a falling edge represents a “0“) "0" "1" "0" "1" "0" "1" " 0" 17050 Fig. 2 - Pulse Distance Coding 17051 "1" " 0" "1" Fig. 3 - Pulse Length Coding The Vishay IR receiver modules were developed and optimised for use in all such carrier frequency burst transmission systems. Standard types are available for the frequencies 30 kHz, 33 kHz, 36 kHz, 38 kHz, 40 kHz, and 56 kHz. In addition to different kinds of coding and different carrier frequencies, there are further variations in the data formats; with and without pre-burst, with different numbers of bits in a command, and with different bit lengths. Almost all codes have address bits and data bits. For reliability reasons, some codes send the data twice, once inverted and once non-inverted. Usually the data command is repeatedly sent as long as the key is being pressed. There Rev. 2.3, 26-Jun-2024 are different ways to distinguish between a multiple key press and an interruption of the transmission link (e.g. to avoid the TV selecting channel “11” when channel “1” was intended). Some codes use a toggle bit, which changes its value at each key-press. Some codes send a pre- or post-burst at the beginning and/or at the end of each key press. And some codes send the data only once for each key-press. Two common data formats, the RC5 code and the NEC code, are described in more detail here. Document Number: 80071 1 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com Vishay Semiconductors THE RC 5 CODE The RC 5 standard uses a bi-phase coding (see Fig. 4) the carrier frequency fixed at 36 kHz. The transmission of a data word begins with two start bits followed by a toggle bit. The toggle bit changes its value at each new key-press. The five address bits represent the address of the device to be controlled. The six command bits contain the information to be transmitted. Each bit in the data word consists of half a bit period with no transmission and half a bit period with a burst of 32 pulses at 36 kHz. The timing is shown in the pulse diagrams. The most suitable IR receivers for receiving the RC5 code are those with “AGC6” in Cyllene 1 (TSOP9...) and Cyllene 2A (TSOP1..) receivers as well as “AGC4” in Cyllene 2C (TSOP3...) and Cyllene 2B (TSOP5...) receivers. For RC5 a band pass frequency of 36 kHz is recommended. Some examples are: TSOP13636, TSOP18636, TSOP34436, TSOP75436, TSOP36436, TSOP99636. 114 ms The data word is repeated as long as a key is pressed Data 24.9 ms Bit length 1.78 ms Example of a data word 2 start bit 1 toggle bit 5 address bit 6 data bit 27.8 µs Burst (half bit) 868 µs (32 cycles of 36 kHz) 17052 Fig. 4 - RC 5 Transmission Code THE NEC CODE The NEC code uses bursts at a carrier frequency of 38 kHz. All Vishay receiver modules operate well with this coding scheme, but the best noise suppression with this format is gained with “AGC6” for Cyllene series and “AGC4” for all other TSOP series (e.g. TSOP13438, TSOP18438, TSOP34438, TSOP75438, TSOP95638, TSOP99638). The NEC code starts the transmission using a so called leader code, a burst with a length of 9 ms, followed by a pause of 4.5 ms and then the data word. The original purpose of this leader code was to let the internal control loops in the receiver modules settle. But such a pre-burst is not necessary for the Vishay receivers to function correctly. After transmitting the data word, only the leader code and a single bit are transmitted repeatedly for as long as a key is pressed. A special property of this code is a constant word length in combination with pulse distance modulation. Both the address and the data bits are transmitted twice, first as Rev. 2.3, 26-Jun-2024 a normal byte followed by an inverted byte. This is shown in Fig. 5. The half period burst portion of each bit contains 22 pulses, each with a width of 8.77 μs and a period of 26.3 μs. A “0” is represented by a pulse distance of 1.125 ms and a “1” by a pulse distance of 2.25 ms. 8 address bits are used to identify the device to be controlled. A further 8 bits are used for the transmission of the command data. As mentioned above, the words are always followed, without a pause, by the inverted words. E.g., the transmission of the address word “00110111” and the command data word “00011010” is performed by sending the bits: “00110111'11001000'00011010'11100101” In a special version of the NEC code, the pre-burst, including all of the address and data bits, is repeated in each 108 ms time slot for as long as the key is pressed. Document Number: 80071 2 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com “Leader code” Vishay Semiconductors Data word 67.5 ms 108 ms 108 ms Address code 4.5 ms 9 ms Address code 8 bit 8 bit 13.5 ms Data code Data code 8 bit 8 bit 27 ms 27 ms 17053 Fig. 5 - NEC Transmission Code DATA TRANSMISSION WITH THE TSDP RECEIVER MODULES Although IR receiver modules are mainly developed and used for IR remote control, they can also serve for continuous data transmission. The AGC 1 setting for example in TSDP34138 is adapted to long burst length supporting the transmission of successive zero bits in RS232. For this purpose, Vishay designed the TSDP series receivers for data transmission, with enhanced output pulse with accuracy. Three proposals for such continuous data encoding are shown below in Fig. 6, Fig. 7, and Fig. 8: Start “1” “0” “0” “1” “0” “1” “1” “0” Stop One byte in RS-232 9600 bps 104 µs (1 bit length, 6 cycles of 56 kHz) Fig. 6 - Example of a Data Transmission at 9600 bps With TSDP34156 Start “1” “0” “0” “1” “0” “1” “1” “0” Stop One byte in RS-232 2400 bps 158 µs (6 cycles of 38 kHz) Fig. 7 - Example of a Data Transmission at 2400 bps with TSDP34138 Rev. 2.3, 26-Jun-2024 Document Number: 80071 3 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com Vishay Semiconductors 107 μs (6 cycles at 56 kHz) 321 μs = “01” 464 μs = “11” 393 μs = “10” 321 μs = “01” 250 μs = “00” Fig. 8 - Example of a Data Transmission With the TSDP34156 COMPATIBILITY OF THE TSOP RECEIVER MODULES WITH DATA FORMATS Vishay offers a variety of IR receiver series in order to supply an optimised solution for each application. Guidelines for selecting the best part for each data format is given here. Basically there are six categories of IR receiver settings regarding noise suppression and data format compatibility. The summary of the features of these AGC types is listed here: • AGC1 is compatible with any coding scheme, it is optimized for continuous data transmission • AGC2 is optimized for most common remote control standard applications with typical long burst data formats • AGC3 is optimized for short burst data formats in noisy environments • AGC4 is optimized for most common remote control standard applications in very noisy environments (including dimmed LCD backlightings) • AGC5 is optimized for short burst data formats in very noisy environments • AGC6 has best sensitivity for NEC and RC5 code in Cyllene 1 (TSOP9...) series receivers and offers high robustness against smart phone interference in Cyllene 2A (TSOP1...) series receivers • AGC-S and AGC-C are optimized for Sony code. This AGC is exclusively designed for Cyllene 2C series receivers The tables below provide an overview of which IR receiver type can be used for the various data formats. CYLLENE 1 IC - COMPATIBILITY FOR DATA FORMATS NEC continuous data frames RC5 code RC6 mode 0 RCMM RECS-80 code R-2000 code (33 kHz) Mitsubishi code 38 kHz Sony code SIRCS 12 bit Sony code SIRCS 15 bit Sony code SIRCS 20 bit r-map data format 38 kHz r-step data format 38 kHz r-step data format for KB 56 kHz XMP code Cisco format 57 kHz Cisco format 37 kHz Low latency protocol - worst case frame 16 bit Low latency protocol - extended frame 24 bit Sejin 4PPM format (38 kHz or 56 kHz) MCIR code keyboard package timing MCIR code pointing device timing MCIR code remote control timing Konka TV data format 2004 RCA code 56 kHz RCA code 38 kHz Panasonic / Kaseikyo command Sharp code Toshiba format Midea Aircon format TCL Sky Mouse format Rev. 2.3, 26-Jun-2024 AGC1 yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes yes AGC2 yes yes yes no no yes yes yes yes yes no no no no yes yes yes yes no yes no no no yes yes yes no yes yes no AGC3 yes yes yes yes yes yes yes no no no yes yes yes yes no no yes no yes no yes yes yes yes no yes yes yes yes yes AGC4 yes yes yes no no yes yes no no no no no yes no no yes yes yes yes no no no no yes yes yes yes yes yes no AGC5 yes yes yes yes yes yes yes no no no yes yes yes yes no yes yes yes yes no yes yes yes yes yes yes yes yes yes yes AGC6 yes yes yes no no yes yes yes yes no no no yes no yes yes yes yes no no no no no yes yes yes yes yes yes no BEST CHOICE AGC6 AGC6 AGC4 AGC3 AGC3 AGC6 AGC6 AGC2 AGC2 AGC2 AGC5 AGC3 AGC4 AGC3 AGC2 AGC6 AGC6 AGC6 AGC4 AGC2 AGC3 AGC3 AGC3 AGC6 AGC4 AGC6 AGC6 AGC4 AGC4 AGC3 Document Number: 80071 4 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com Vishay Semiconductors CYLLENE 2A IC (Mneme Replacement) - COMPATIBILITY FOR DATA FORMATS AGC1 AGC2 AGC3 AGC4 AGC5 AGC6 BEST CHOICE NEC continuous data frames yes yes yes yes yes yes AGC4 RC5 code yes yes yes yes yes yes AGC6 RC6 mode 0 yes yes yes yes yes no AGC4 RCMM yes no yes no yes no AGC3 RECS-80 code yes no yes no yes no AGC5 R-2000 code (33 kHz) yes no yes yes yes no AGC4 Mitsubishi code 38 kHz yes no yes yes yes no AGC4 Sony code SIRCS 12 bit yes yes yes no no no AGC2 Sony code SIRCS 15 bit yes yes yes no no no AGC2 Sony code SIRCS 20 bit yes yes no no no no AGC2 r-map data format 38 kHz yes no yes no yes no AGC3 r-step data format 38 kHz yes no yes no yes no AGC4 r-step data format for KB 56 kHz yes no yes yes yes no AGC4 XMP code yes no yes no yes no AGC3 Cisco format 57 kHz yes yes no no no no AGC2 Cisco format 37 kHz yes yes yes yes yes yes AGC4 Low latency protocol - worst case frame 16 bit yes yes yes yes no yes AGC4 Low latency protocol - extended frame 24 bit yes yes yes yes no yes AGC4 Sejin 4PPM format (38 kHz or 56 kHz) yes no yes yes yes no AGC4 MCIR code keyboard package timing yes no yes yes yes no AGC3 MCIR code pointing device timing yes no yes yes yes no AGC3 MCIR code remote control timing yes no yes yes yes no AGC3 Konka TV data format 2004 yes yes yes yes yes yes AGC4 RCA code 56 kHz yes yes yes yes no yes AGC6 RCA code 38 kHz yes yes yes yes yes yes AGC4 Panasonic / Kaseikyo command yes no yes yes yes no AGC4 Sharp code yes no yes yes yes no AGC4 Toshiba format yes yes yes yes yes yes AGC4 Midea Aircon format yes yes yes yes yes yes AGC4 TCL Sky Mouse format yes no yes no yes no AGC3 Rev. 2.3, 26-Jun-2024 Document Number: 80071 5 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com Vishay Semiconductors CYLLENE 2B IC (Methone Replacement) - COMPATIBILITY FOR DATA FORMATS AGC1 AGC2/8 AGC3 AGC4 AGC5 BEST CHOICE NEC continuous data frames yes yes yes yes yes AGC4 RC5 code yes yes yes yes yes AGC4 RC6 mode 0 yes yes yes yes yes AGC4 RCMM yes no yes no yes AGC3 RECS-80 code yes no yes no yes AGC3 R-2000 code (33 kHz) yes yes yes yes yes AGC4 Mitsubishi code 38 kHz yes yes yes yes yes AGC4 Sony code SIRCS 12 bit yes yes yes no no AGC2 Sony code SIRCS 15 bit yes yes yes no no AGC2 Sony code SIRCS 20 bit yes yes no no no AGC2 r-map data format 38 kHz yes no yes no no AGC3 r-step data format 38 kHz yes no yes yes yes AGC4 r-step data format for KB 56 kHz yes yes yes yes no AGC4 XMP code yes no yes no yes AGC3 Cisco format 57 kHz yes yes yes yes no AGC4 Cisco format 37 kHz yes yes no no no AGC2 Low latency protocol - worst case frame 16 bit yes yes yes yes no AGC4 Low latency protocol - extended frame 24 bit yes yes yes yes no AGC4 Sejin 4PPM format (38 kHz or 56 kHz) yes yes yes yes no AGC4 MCIR code keyboard package timing yes yes yes yes yes AGC3 MCIR code pointing device timing yes yes yes yes yes AGC3 MCIR code remote control timing yes yes yes yes yes AGC3 Konka TV data format 2004 yes yes yes yes yes AGC4 RCA code 56 kHz yes yes yes yes yes AGC4 RCA code 38 kHz yes yes yes yes no AGC4 Panasonic / Kaseikyo command yes yes yes yes yes AGC4 Sharp code yes yes yes yes yes AGC4 Toshiba format yes yes yes yes yes AGC4 Midea Aircon format yes no yes yes yes AGC4 TCL Sky Mouse format yes no yes no yes AGC3 Rev. 2.3, 26-Jun-2024 Document Number: 80071 6 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000 Data Formats www.vishay.com Vishay Semiconductors CYLLENE 2C IC (Aether Replacement) - COMPATIBILITY FOR DATA FORMATS AGC1 AGC2 AGC3 AGC4 AGC5 AGCS BEST CHOICE NEC continuous data frames yes yes yes yes yes yes AGC4 RC5 code yes yes yes yes yes yes AGC4 RC6 mode 0 yes yes yes yes yes yes AGC4 RCMM yes no yes no yes no AGC3 RECS-80 code yes no yes no yes no AGC3 R-2000 code (33 kHz) yes yes yes yes yes yes AGC4 Mitsubishi code 38 kHz yes yes yes yes no yes AGC4 Sony code SIRCS 12 bit yes yes yes no no yes AGCS Sony code SIRCS 15 bit yes yes no no no yes AGCS Sony code SIRCS 20 bit yes yes no no no yes AGCS r-map data format 38 kHz yes no yes no yes no AGC3 r-step data format 38 kHz yes no yes no yes no AGC3 r-step data format for KB 56 kHz yes no yes no yes no AGC3 XMP code yes no yes no yes no AGC3 Cisco format 57 kHz yes yes yes yes no yes AGC4 Cisco format 37 kHz yes yes no no no no AGC2 Low latency protocol - worst case frame 16 bit yes yes yes yes no yes AGC4 Low latency protocol - extended frame 24 bit yes yes yes yes no yes AGC4 Sejin 4PPM format (38 kHz or 56 kHz) yes no yes no yes yes AGC3 MCIR code keyboard package timing yes yes no no no yes AGC2 MCIR code pointing device timing yes no yes no no no AGC3 MCIR code remote control timing yes no yes no yes no AGC3 Konka TV data format 2004 yes no yes no no no AGC3 RCA code 56 kHz yes yes yes yes yes yes AGC4 RCA code 38 kHz yes yes yes yes yes yes AGC4 Panasonic / Kaseikyo command yes yes yes yes no no AGC4 Sharp code yes yes yes yes yes yes AGC4 Toshiba format yes yes yes yes yes yes AGC4 Midea Aircon format yes yes yes yes yes yes AGC4 TCL Sky Mouse format yes yes yes yes yes yes AGC4 NEC continuous data frames yes no yes no yes no AGC3 Rev. 2.3, 26-Jun-2024 Document Number: 80071 7 For technical questions, contact: [email protected] THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000