logiUART - What is software driven TX ("break" signal) and "break" error and how to use it
What is software driven TX ('break' signal) and 'break' error and how to use it?

logiUART supports software driven TX signal ('break' signal). While BREAK bit in SW_HS Register is active, the logiUART forces the transmitter data output TX low to alert the communication terminal. The break's duration must be longer than the character's duration in order to be recognized. A software driver should assure it.

A “break” error is a break condition when the RX line stays low throughout the start, data, parity and first stop bit. Every received character is checked for a “break” error. When detected a zero character with an active associated break flag is transferred to the RX FIFO. The BREAK_DT break flag in RX_STATUS_REG is set when this data item gets to the top of the RX FIFO. Reading of the RX status register or software reset clears this status bit. Also, RD_BREAK status is set in RX_DATA_STATUS_REG. If the core is configured without the RX data status fifo (the parameter C_USE_RX_STAT is unchecked) then, if read, values from the RX_DATA_STATUS_REG register are 0. After the break condition is detected the receiver continues RX line monitoring until it returns to high condition.

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