Multidrop bus

A multidrop bus (MDB) is a computer bus in which all components are connected to the electrical circuit. A process of arbitration determines which device sends information at any point. The other devices listen for the data they are intended to receive.

Multidrop buses have the advantage of simplicity and extensibility. However, modern SDRAM chips exemplify the problem of electrical impedance discontinuity. Fully Buffered DIMM is an alternative approach to connecting multiple DRAM modules to a memory controller. Since 2000, multidrop standards such as PCI and Parallel ATA are increasingly being replaced by point-to-point systems such as PCI Express and SATA.

MDB in Vending Machines

The multidrop bus used by vending machine controllers to communicate with the vending machine's components, such as a currency detector, is also called MDB (for MultiDropBus). In use since the 1980s, it is now an open standard of the National Automatic Merchandising Association, or NAMA. The devices communicate in a single-master, multiple-slave configuration using the MDB protocol, which is based on a Motorola 9-bit UART implemented as an 8-bit data value with an additional mode bit. The mode bit differentiates between ADDRESS and DATA bytes. The master sends messages containing one address byte and a variable number of data bytes. The bus "slave devices" listen for an address, and if it matches their address that slave device will process the message and respond to the master. Though 9-bit compliant UARTs are not popular in PCs, they can be found in many microcontrollers.

Drop

Drop, DROP, drops or DROPS may refer to:

Places

Computers and technology

Confectionery

Sports

Drop (Timbaland & Magoo song)

"Drop" is a hip-hop song by American hip-hop duo Timbaland & Magoo, released as the first official single from their second studio album, Indecent Proposal. The track features rapper and DJ Fatman Scoop. A music video (directed by Chris Robinson (director)) for the single was filmed in May 2001 and premiered on BET in early June 2001. Since the single was released strictly via radio airplay it did not receive a physical release till November 13, 2001, a week prior to the album's release. The track is also featured on Def Jam Fighters III.

Track listing

Charts

References

Drop (music)

A drop in popular music, especially electronic music styles, is a point in a music track where a switch of rhythm or bass line occurs and usually follows a recognizable build section and break.

The term "drop" comes from the composer or producer "dropping in" the primary rhythmic and foundational elements previously hinted at into the mix more or less at once. Related terms, typically describing certain types of drops, include "beat-up" (so named because it is a point where the producer brings up the foundational kick drum beat after having faded it down during a break or buildup) and "climax" (typically describing a single particularly striking drop heard late in the track).

Types

Many genres of EDM can have more than one drop during a track, especially if the song is built on a "dance-pop" verse/chorus with vocals; a drop of some kind is typically heard somewhere during each chorus as the high point of that verse/chorus cycle. Most genres, however, tend to emphasize a single drop as the beginning of the high point, or climax, of the entire track; in vocal subgenres this is typically the last repetition of the chorus, while in nonvocal genres it typically occurs in the last quarter of the track.