Re: Help regarding UART

AN2371.pdf

2.1.1 void tpu_uart_transmit_init

baud_rate :-

    Baud rate is a measure of the number of times per second a signal 
    in a communications channel varies, or makes a transition between 
    states (states being frequencies,
    voltage levels, or phase angles). One baud is one such change. 
    Thus, a 300-baud modem's signal
    changes state 300 times each second, while a 600- baud modem's 
    signal changes state 600 times
    per second. The baud_rate value is the number of TCR1 counts per 
    bit time, and is calculated by
    the following equation:

    TCR1 counts/second
    ------------------
    number of transitions (baud/second)

Therefore baud_rate = TCR1/9600
If TCR1 counts/second is 10000000 for a 40MHz system clock
baud_rate = 10000000/9600 = 1041.667d
baud_rate = 0x411

So I don't know how they get their value of 0x01B2!
TCR1 might be different but I still can't get their answer!

Maybe Freescale could use this sentence as a get-out ...

The baud rate is set to approximately 9600 baud. The actual baud rate
depends on the clock frequency of the MCU, and the prescaler value
chosen.




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