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47-706: The show originally started in 1977 at the Bloomsbury Crest, London, launching under the name of Discotek 77. In 1982, whilst still at the Bloomsbury Crest, it was renamed the BADEM Light & Sound Show to mirror the name of the fledgling trade association that had been set up for the sector - the British Association of Discotheque Equipment Manufacturers. BADEM was subsequently renamed the Professional Lighting and Sound Association (PLASA) and thus in 1984,

94-411: A multi-drop bus topology with nodes strung together in what is commonly called a daisy chain . A network consists of a single DMX512 controller – which is the master of the network — and one or more slave devices . For example, a lighting console is frequently employed as the controller for a network of slave devices such as dimmers , fog machines and intelligent lights . Each slave device has

141-504: A 25% increase in the number of audio companies exhibiting.” The 2018 show was a further success with a “4% increase in visitors with a palpable atmosphere that was reminiscent of its popular Earls Court days.” For much of its history, the show was run by an external events company, however in 2007, PLASA took the management of the event in-house and launched PLASA Events Ltd. which is still in operation. PLASA#History The Professional Lighting and Sound Association ( PLASA )

188-500: A 5-pin XLR connector on the product. In such cases all the following additional requirements shall be met: 1) The alternate connector shall not be any type of XLR connector. 2) The alternate connector shall not be any type of IEC 60603-7 8-position modular connector except as allowed in clause 7.3. 7.2 Equipment intended for fixed installation with internal connections to the data link Fixed installation products with internal connections to

235-503: A DMX512 "IN" connector and usually an "OUT" (or "THRU") connector as well. The controller, which usually has only an OUT connector, is connected via a DMX512 cable to the IN connector of the first slave. A second cable then links the OUT or THRU connector of the first slave to the IN connector of the next slave in the chain, and so on. For example, the block diagram below shows a simple network consisting of

282-400: A controller and three slaves. The specification requires a 'terminator' to be connected to the final OUT or THRU connector of the last slave on the daisy chain, which would otherwise be unconnected. A terminator is a stand-alone male connector with an integral 120  Ω resistor connected across the primary data signal pair; this resistor matches the cable's characteristic impedance . If

329-549: A hard connection between signal common and ground are permitted but their use is strongly discouraged. Several possible grounding configurations that are commonly used with EIA485 are specifically disallowed by E1.11. The original DMX512 1990 specified that where connectors are used, the data link shall use five-pin XLR style electrical connectors (XLR-5), with female connectors used on transmitting (OUT) ports and male connectors on receiving ports. The use of any other XLR-style connector

376-778: A nominal characteristic impedance of 120 Ω . Also, cables designed for EIA485 typically meet the DMX512 electrical specifications. Conversely, microphone and line-level audio cables lack the requisite electrical characteristics and thus are not suitable for DMX512 cabling. The significantly lower impedance and higher capacitance of these cables distort the DMX512 digital waveforms, which in turn can cause irregular operation or intermittent errors that are difficult to identify and correct. Cat5 cable , commonly used for networking and telecommunications, has been tested by ESTA for use with DMX512A. RJ45 connectors are used by some DMX-compatible hardware with ESTA standard or proprietary pinouts. At

423-443: A packet. However, it does require that packets be transmitted so that the leading edges of any two sequential BREAKs must be separated by at least 1204 μs, and receivers must be able to handle packets with break-to-break times as short as 1196 μs. The minimum break-to-break transmit time can be achieved by sending packets that contain at least 24 slots (by adding extra padding bytes, if necessary) or by stretching parameters such as

470-627: A revision process to develop the standard as an ANSI standard. The resulting revised standard, known officially as "Entertainment Technology—USITT DMX512-A—Asynchronous Serial Digital Data Transmission Standard for Controlling Lighting Equipment and Accessories", was approved by the American National Standards Institute (ANSI) in November 2004. It was revised again in 2008, and is the current standard known as "E1.11 – 2008, USITT DMX512-A", or just "DMX512-A". A DMX512 network employs

517-400: A secondary data pair is used, a termination resistor is connected across it as well. Although simple systems ( i.e. , systems having few devices and short cables) will sometimes function normally without a terminator, the standard requires its use. Some DMX slave devices have built-in terminators that can be manually activated with a mechanical switch or by software, or by automatically sensing

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564-520: A single OUT connector, enabling them to control only one universe, whereas large control desks (operator consoles) may have the capacity to control multiple universes, with an OUT connector provided for each universe. Many of the more modern control desks instead of featuring multiple OUT connectors have an unshielded twisted pair connector (such as Cat 5 , Cat 5e or Cat 6 ). Such cables and systems can control up to 524,288 universes of DMX512 (32,768 subnets × 16 universes per subnet) using

611-436: A single bus. If more than 32 unit loads need to communicate, the network can be expanded across parallel buses using DMX splitters. Network wiring consists of a shielded twisted pair , with a characteristic impedance of 120 Ω , with a termination resistor at the end of the cable furthest from the controller to absorb signal reflections. DMX512 has two twisted pair data paths, although the specification currently only defines

658-622: A three-day residential event in Gatwick, UK for lighting technicians and developers to test the interoperability of their products. This event returns in 2019 taking place in Lille, France. DMX512 DMX512 is a standard for digital communication networks that are commonly used to control lighting and effects. It was originally intended as a standardized method for controlling stage lighting dimmers, which, prior to DMX512, had employed various incompatible proprietary protocols . It quickly became

705-600: A unidirectional EIA-485 (RS-485) differential signaling at its physical layer, in conjunction with a variable-size, packet-based communication protocol . DMX512 does not include automatic error checking and correction and therefore is not an appropriate control for hazardous applications, such as pyrotechnics or movement of theatrical rigging . However, it is still used for such applications. False triggering may be caused by electromagnetic interference , static electricity discharges, improper cable termination , excessively long cables, or poor quality cables. The DMX standard

752-424: A wide variety of devices; this version recognizes this fact. Each NULL START Code packet contains no formal data or addressing structure. The device using data from the packet must know the position of that data within the packet. Dimmer packs or racks use a group of slots to determine the levels for their dimmers. Typically a dimmer has a starting address that represents the lowest-numbered dimmer in that pack, and

799-620: Is a trade association headquartered in Eastbourne , United Kingdom . Its membership is made up of companies involved with the events and entertainments technology sector. PLASA was originally known as the British Association of Discothèque Equipment Manufacturers (BADEM), a name used between 1976 and 1983. In 2010 PLASA merged with the Entertainment Services and Technology Association . and demerged in 2015. John Simpson,

846-401: Is further recommended that receivers have a high impedance connection between signal common and ground; such ports are referred to as isolated . The standard also allows for isolated transmitter ports and non-isolated receivers. It also recommends that systems ground the signal common at only one point, in order to avoid the formation of disruptive ground loops . Grounded receivers that have

893-478: Is not compliant with the DMX standard, but may be sufficiently compatible for operation using simple adapters. Note: There is a risk of equipment damage if 3-pin XLR audio and DMX signals are plugged into each other. Note: This connector is prohibited by section 7 of ANSI E1.11 - 2008. Data 1+ and - are often swapped over. The most commonly encountered pinout is given first: Color Kinetics has their own version of

940-489: Is prohibited. The three-pin XLR connector is commonly used for DMX512, on lighting and related control equipment, particularly at the budget/DJ end of the market. However, using three-pin XLR connectors for DMX512 is specifically prohibited by section 7.1.2 of the DMX512 standard. Use of the three-pin XLR in this context firstly presents a risk of damage to the lighting equipment should an audio cable carrying 48-volt phantom power be accidentally connected, and secondly encourages

987-522: Is published by the Entertainment Services and Technology Association (ESTA), and can be downloaded from its website. Developed by the Engineering Commission of United States Institute for Theatre Technology (USITT), the DMX512 standard (for digital multiplex with 512 pieces of information ) was created in 1986, with subsequent revisions in 1990 leading to USITT DMX512/1990. In 1998 the ESTA began

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1034-611: The Art-Net IV protocol, or 65,536 universes using the sACN protocol, and the existing Ethernet in buildings. DMX512 data is transmitted over a differential pair using EIA-485 voltage levels. DMX512 electrical specifications are identical to those of the EIA-485-A standard, except where stated otherwise in E1.11 . DMX512 is a bus network no more than 400 metres (1,300 ft) long, with not more than 32 unit loads (individual devices connected) on

1081-474: The RDM extension to DMX (0xCC), and various proprietary systems. ESTA maintains a database of alternate start codes. All slots following the start code contain control settings for slave devices. A slot's position within the packet determines the device and function to be controlled while its data value specifies the control set point. DMX512 timing parameters may vary over a wide range. The original authors specified

1128-419: The data link layer , a DMX512 controller transmits asynchronous serial data at 250 kbit/s. The data format is fixed at one start bit, eight data bits (least significant first ), two stop bits and no parity . Each frame consists of: The start of a packet is signified by a break followed by a "mark" (a logical one), known as the "Mark After Break" (MAB). The break, which signals the end of one packet and

1175-424: The 2016 show would move back to West London and be hosted at Olympia . During its time at ExCeL PLASA had been hosted during the month of October - prior to this the show was typically held during September. Upon its move to Olympia, the show moved back to September. The show has remained at Olympia since 2016 and in 2017 celebrated its 40th anniversary “with an increase in visitor numbers, a sold-out show floor and

1222-575: The BREAK, MAB, Interslot, or Interpacket times. Most data is sent with the default Null Start Code of 00h. Quoting from the standard: 8.5.1 NULL START code A NULL START Code identifies subsequent data slots as a block of un-typed sequential 8-bit information. Packets identified by a NULL START Code are the default packets sent on DMX512 networks. Earlier versions of this standard assumed that only dimmer class data would be sent using NULL START Code packets. In practice NULL START Code packets have been used by

1269-505: The PLASA Governing Body Chair at the time, said "This has been a difficult period for PLASA but it is also an opportunity for us to refocus. PLASA has a chance to reassess its role in this industry, its relationships and communications with its members, and the future directions of its commercial activities." Also during this time PLASA Show was relocated to Earls Court and CEO Matthew Griffiths left his post. Peter Heath took

1316-472: The RJ-45 connector for DMX, which predates the 2008 official inclusion in the DMX512 standard. The pinout specifically for Color Kinetics LED lighting products is: The standard cables used in DMX512 networks employ XLR5 connectors , with a male connector on one end and a female connector on the other end. The cable's male connector attaches to the transmitting, female jack (OUT), and its female connector attaches to

1363-410: The absence of a connected cable. A DMX512 network is called a "DMX universe". Each OUT connector on a DMX512 controller can control a single universe. A DMX512 universe is made up of 512 channels, with each channel containing a value between 0 and 255. Each slave device in the chain can "look at" a different set of channels in order to be controlled by the master controller. Smaller controllers may have

1410-554: The addressing increases from there to the highest-numbered dimmer. As an example, for two packs of six dimmers each, the first pack would start at address 1 and the second pack at address 7. Each slot in the DMX512 packet corresponds to one dimmer. DMX does not mandate a method of 16-bit encoding for Null Start Code packets; however, many parameters of moving lights make use of encoding larger than 8-bit numbers. To control these parameters more accurately, some fixtures use two channels for parameters that require greater accuracy. The first of

1457-451: The conductor pairing scheme used by Category 5 (Cat5) twisted pair patch cables. The avoidance of pins 4 and 5 helps to prevent equipment damage, if the cabling is accidentally plugged into a single-line public switched telephone network phone jack. In the early days of digital lighting control, several equipment manufacturers employed various connectors and pinouts for their proprietary digital control signals. The most common of these

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1504-493: The data link may use the 5-pin XLR connector, but shall not use any other XLR connector. When use is made of the 5-pin XLR connector, the requirements of 7.1 and 7.1.1 shall apply. When a non-XLR connector is used, this Standard makes no other restriction or stipulation on connector choice. The contact (pin) numbering on the alternate connector should match numbering for the standard 5-Pin XLR The 8P8C modular connector pinout matches

1551-411: The development of a UK National Rigging Certificate, which launched in 2007 for individuals working in the entertainments rigging industry. Each year, PLASA hands out PLASA Awards for Innovation and Sustainability Award. The PLASA Awards for Innovation aim to emphasise this focus on true innovation. The procedure ensures that all nominated products are vetted to show that they offer something new to

1598-496: The industry. PLASA has been a part of the European Ecodesign Coalition which includes prominent industry bodies from across Europe. The purpose of the coalition has been to campaign against Ecodesign lighting regulations and propose exemptions for stage lighting. In 2018 PLASA collaborated with Hamish Dumbreck of JESE Ltd, Peter Willis of Howard Eaton Lighting and Wayne Howell of Artistic Licence to present Plugfest,

1645-420: The last slot of the packet and the break (MBB) can be as long as desired. A maximum-sized packet, which has 512 channels (slots following the start code), takes approximately 23 ms to send, corresponding to a maximum refresh rate of about 44 Hz. For higher refresh rates, packets having fewer than 512 channels can be sent. The standard does not specify the minimum number of slots that can be sent in

1692-424: The late 2000s when users of radio microphones and similar devices complained that their equipment would be rendered unusable as a result of proposed plans to auction the radio spectrum utilised by many of such devices as part of the digital television switchover . After merging with ESTA , PLASA took on the role of maintaining the industry standards for DMX512 and RDM . PLASA have also been responsible for

1739-473: The primary method for linking controllers (such as a lighting console ) to dimmers and special effects devices such as fog machines and intelligent lights . DMX512 has also expanded to uses in non-theatrical interior and architectural lighting, at scales ranging from strings of Christmas lights to electronic billboards and stadium or arena concerts. It can now be used to control almost anything, reflecting its popularity in all types of venues. DMX512 uses

1786-771: The receiving, male jack (IN). Cabling for DMX512 was removed from the ANSI E1.11 standard and a separate cabling standards project was started in 2003. Two cabling standards have been developed, one for portable DMX512 cables (ANSI E1.27-1 – 2006) and one for permanent installations (draft standard BSR E1.27-2). This resolved issues arising from the differences in requirements for cables used in touring shows versus those used for permanent infrastructure. The electrical characteristics of DMX512 cable are specified in terms of impedance and capacitance, although there are often mechanical and other considerations that must be considered as well. Cable types that are appropriate for DMX512 usage will have

1833-819: The role of CEO in April of 2016. In the same year PLASA Show move back to the West London venue London Olympia. Since then, PLASA Show has steadily regained popularity with the 2018 edition of the show being the “busiest and most vibrant show in recent history”. PLASA's activities include lobbying , organising trade show events (including the PLASA Show ), publishing both technical and industry news products (such as Lighting & Sound International and Lighting & Sound America ), developing industry standards and developing industry certification schemes. PLASA performed lobbying of Ofcom and other British Government entities in

1880-657: The show became the PLASA Light and Sound Show. In 1985, it relocated to the Novotel in Hammersmith , then to Olympia 2 in 1988, where it stayed until 1992 before transferring to the larger Earls Court 2 . It made the move from Earls Court 2 to Earls Court 1 in 1996 and in 2007 opened the doors back to Earls Court 2 and occupied both halls. In 2013 the show moved to the ExCeL exhibition centre. It stayed here for 3 years, announcing that

1927-450: The standard this way to provide the greatest design flexibility. Because of this, however, it was difficult to design receivers that operated over the entire timing range. As a result of this difficulty, the timing specification of the original 1986 standard was changed in 1990. Specifically, the MAB, which was originally fixed at 4 μs, was changed to 8 μs, minimum. The E1.11 (2004) standard relaxed

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1974-418: The standard. Other form-factors of connectors are permitted on equipment where the XLR and RJ-45 would not fit or are considered inappropriate, for example on equipment intended for permanent installation. From ANSI E1.11 - 2008 section 7: 7.1.2 Concession for use of an alternate connector (NCC DMX512-A) A concession to use an alternate connector is available only when it is physically impossible to mount

2021-569: The start of another, causes receivers to start reception and also serves as a frame (position reference) for data bytes within the packet. Framed data bytes are known as slots . Following the break, up to 513 slots are sent. The first slot is reserved for a "Start Code" that specifies the type of data in the packet. A start code of 0x00 ( hexadecimal zero) is the standard value used for all DMX512 compatible devices, which includes most lighting fixtures and dimmers. Other start codes are used for Text packets (0x17), System Information Packets (0xCF), for

2068-407: The transmitter and receiver timing specifications. This relaxed the timing requirements for systems using controllers built to DMX512-A (E1.11); however, a significant number of legacy devices still employ transmit timing near the minimum end of the range. Maximum times are not specified because as long as a packet is sent at least once per second, the BREAK, MAB, inter-slot time, and the mark between

2115-433: The use of cable following analog audio specifications for DMX, which can lead to signal degradation and unreliable operation of the DMX network. DMX512-A (ANSI E1.11-2008) defined the use of eight-pin modular ( 8P8C , or "RJ-45") connectors for fixed installations where regular plugging and unplugging of equipment is not required. Note: Several manufacturers used other pinouts for RJ-45 connectors prior to this inclusion in

2162-429: The use of one of the twisted pairs. The second pair is undefined but required by the electrical specification. The E1.11 (DMX512 2004) electrical specification addresses the connection of DMX512 signal common to earth ground. Specifically, the standard recommends that transmitter ports (DMX512 controller OUT port) have a low impedance connection between signal common and ground; such ports are referred to as grounded . It

2209-465: Was the three-pin XLR connector (also called cannon jack in some countries). When DMX512 was ratified, many of these manufacturers then issued firmware updates to enable the use of DMX512 control on their existing equipment by the use of a simple adapter to and from the standard 5-pin XLR style connector. As the electrical specification currently only defines a purpose for a single wire pair, some equipment manufacturers continue to use it. Such equipment

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