![]() If you have RS232 equipment that will probably be sending something like -12 V for a 1-bit, and +12 V for a 0-bit. That is, a 1-bit is HIGH and a 0-bit is LOW. The bits shown here (logic-level) are not inverted. The only real way to recover from this is to have a large enough gap, from time to time, (eg. If you start listening to serial data in the middle of a stream, it is quite possible that a 0-bit in the middle of the stream will be interpreted as a start bit, and then the receiver will interpret everything after that incorrectly. In the "olden days" this was so that slow electromechanical equipment could process the previous byte (eg. This basically just lengthens the time between bytes. Therefore you can't have both 9 data bits and a parity bit. In the case of 9 data bits (as used in the SeaTalk protocol) the parity bit is re-purposed as a 9th data bit. The parity bit is sent before the stop bit. This can help the receiver detect if the data arrived correctly or not.
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