A multidrop bus (MDB) is a
computer bus in which all components are connected to the electrical circuit. A process of
arbitration
Arbitration is a form of alternative dispute resolution (ADR) that resolves disputes outside the judiciary courts. The dispute will be decided by one or more persons (the 'arbitrators', 'arbiters' or ' arbitral tribunal'), which renders the ...
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, but their differing electrical characteristics make them relatively unsuitable for high frequency or high bandwidth applications.
In computing
Since 2000, multidrop standards such as
PCI and
Parallel ATA are increasingly being replaced by
point-to-point systems such as
PCI Express
PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common m ...
and
SATA
SATA (Serial AT Attachment) is a computer bus interface that connects host adapter, host bus adapters to mass storage devices such as hard disk drives, optical drives, and solid-state drives. Serial ATA succeeded the earlier Parallel ATA (PATA) ...
. 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.
For vending machines
MDB/ICP
MDB/ICP (formerly known as MDB) is a multidrop bus computer networking protocol used within the vending machine industry, currently published by the American
National Automatic Merchandising Association.
ccTalk
The ccTalk multidrop bus protocol uses an
TTL-level asynchronous serial protocol. It uses address randomization to allow multiple similar devices on the bus (after randomisation the devices can be distinguished by their serial number). ccTalk was developed by CoinControls, but is used by multiple vendors.
See also
*
Bus network topology
*
EIA-485
*
1-Wire
*
Open collector
External links
IBM Journal of Research and Development
{{DEFAULTSORT:Multidrop Bus
Computer buses