UART & RS232

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Universal Asynchronous Transmitter Receiver

Charactercode.png
LSB first.Each character is sent as a logic low start bit, a configurable number of data bits (usually 7 or 8, sometimes 5), an optional parity bit, and one or more logic high stop bits.
RS232 is standard to control the signaling

RTS/CTS handshaking:
DTE assert Ready to send (RTS) signal to DCE ,DCE reply by asserting Clear to send (CTS) in older RS232,Still in RS-232 to RS-485 bus converter use this mechanism to check bus mastering.

DTE :data terminating Equipment (e.g. desktop)
DCE:data circuit terminating equipment


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