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CHAPTER 20 LIN-UART
20.7.1 Operation in Asynchronous Mode (Op. Modes 0 and 1)
When LIN-UART is used in operation mode 0 (normal mode) or operation mode 1
(multiprocessor mode), the asynchronous transfer mode is selected.
■ Operation in Asynchronous Mode
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Transfer data format
Generally each data transfer in the asynchronous mode operation begins with the start bit (low-level) and
ends with at least one stop bit (high-level). The direction of the bit stream (LSB first or MSB first) is
determined by the BDS bit of the Serial Status Register (SSR). The parity bit (if enabled) is always placed
between the last data bit and the (first) stop bit.
In operation mode 0 the length of the data frame can be 7 or 8 bits, with or without parity, and 1 or 2 stop
bits.
In operation mode 1 the length of the data frame can be 7 or 8 bits with a following address-/data-selection
bit instead of a parity bit. 1 or 2 stop bits can be selected.
The calculation formula for the bit length of a transfer frame is:
Length = 1 + d + p + s
(d = number of data bits [7 or 8], p = parity [0 or 1], s = number of stop bits [1 or 2]
Figure 20.7-1 shows the data format in the asynchronous mode.