Difference between revisions of "Serial line"

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* [[asynchronous serial line]]s, in which the format is self-[[clock]]ing (i.e. the start location of each character can be inferred from the data stream), and
 
* [[asynchronous serial line]]s, in which the format is self-[[clock]]ing (i.e. the start location of each character can be inferred from the data stream), and
 
* [[synchronous serial line]]s, where each character starts immediately after the previous one, and is therefore not self-clocking
 
* [[synchronous serial line]]s, where each character starts immediately after the previous one, and is therefore not self-clocking
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Both serial line [[protocol]]s requires two signal levels: idle (mark, high), and asserted (space, low). (The polarity is a legacy from telegraphy, where the line was held high in order to show that the line was not broken, and that the transmitter was functional.)
  
 
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[[Category: Communication Basics]]
 
[[Category: Communication Basics]]

Latest revision as of 16:11, 21 March 2020

A serial line is a means of transmitting data in bit serial fashion, often over a communication link such as a telephone line. There are two principal forms:

Both serial line protocols requires two signal levels: idle (mark, high), and asserted (space, low). (The polarity is a legacy from telegraphy, where the line was held high in order to show that the line was not broken, and that the transmitter was functional.)