<architecture> Not synchronised by a shared signal such as clock or semaphore, proceeding independently.
1. <operating system> A process in a multitasking system whose execution can proceed independently, "in the background". Other processes may be started before the asynchronous process has finished.
2. <communications> A communications system in which data transmission may start at any time and is indicated by a start bit, e.g. EIA-232. A data byte (or other element defined by the protocol) ends with a stop bit. A continuous marking condition (identical to stop bits but not quantized in time), is then maintained until data resumes.
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Nearby terms: asymmetrical modulation « Asymmetric Digital Subscriber Line « Asymmetric Digital Subscriber Loop « asynchronous » Asynchronous Balanced Mode » Asynchronous Communications Interface Adapter » asynchronous logic