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Note:
For more information on programming the Prescaler and Baud Rate Generator, consult
the XR17D158 datasheet.
The Baud Rate Generator divisor can be calculated by one of the following equations depending
on sampling of receiver of 8 or 16:
Divisor = (INPUT_CLOCK / PRESCALER) / (DESIRED_BAUD_RATE x 16)
or
Divisor = (INPUT_CLOCK / PRESCALER) / (DESIRED_BAUD_RATE x 8)
For example, if one wants to use a baud rate of 115.2K, Prescale divisor of 4, and receiver
sampling of 16, the Baud Rate Generator divisor would be:
(14745600 / 4) / (115200 x 16) = 2
If the desired baud rate can not be expressed as a whole number divisor, it may be necessary to
use a different input clock. This can be done with a User Oscillator. A user-specified oscillator
can be installed in U3. The max frequency for the user oscillator is 50 MHz and the max baud
rate for the chip is 6.25 Mbps. Alternatively, RTD can preinstall several common oscillator
frequencies.
