Synchronous data transfer
With synchronous data transmission , the transmission of individual bits between the transmitter and receiver is time-synchronized with a clock signal . This clock signal can be sent via its own interface line or can be recovered from the data signal by the receiver. One then speaks of " clock recovery ".
A synchronous transmission of signals exists when there is a rigid phase relationship between them over several symbol characters. A necessary condition for this is that the same clock frequencies must exist between the transmitter and receiver.
The counterpart is asynchronous data transmission , in which pauses of any length (or randomly long) can occur between individual groups of symbols, which means that there is no longer a rigid phase relationship.
Demarcation
Synchronous data transmission should not be confused with the term synchronous communication , which refers to the sequence of request and response in a transmission protocol .
literature
- Jörg Rech: Ethernet . Technologies and protocols for computer networking, 3rd updated edition, Heise Zeitschriften Verlag GmbH & Co KG, Hanover 2014, ISBN 978-3-944099-04-0 .
- Hartmut Ernst, Jochen Schmidt, Gerd Beneken: Basic course in computer science . Basics and concepts for successful IT practice - A comprehensive, practice-oriented introduction, 6th edition, Springer Fachmedien, Wiesbaden 2016, ISBN 978-3-658-14633-7 .
- Hartmut Ernst: Basics and concepts of computer science . Volume I, 2nd edition, Friedrich Vieweg Verlag, Wiesbaden 2000, ISBN 978-3-528-15717-3 .
Web links
- The serial synchronous data transmission (accessed on September 28, 2017)
- Microcomputer (accessed September 28, 2017)