XR88C681CP Datasheet, PDF (54/99 Pages) Exar Corporation – CMOS DUAL CHANNEL UART (DUART)

XR88C681
D.3.1 Timer Mode:
Please note that of the two C/T Modes, the Timer Mode is
the only mode which is relevant to the function of Bit Rate
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D.5 Clock Select Registers, CSRA and CSRB
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