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baud rate calculation

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Tan

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please let me know how is baudrate calculated. for example if i need 2400 with 100mhz clock how shouls i calculate it.
 

without complete detail , members may not be able to give any feedback.
 

What details are required here?.I need to design a uart with baud rate 2400.My FPGA clock is 100MHz.so how should i calculate the value in order to get baudrate 2400.
I hope I am clear now.
 

Most UART´s need a clock at 16 times the baud rate.
In this case 2400*16 = 38400 Hz

To generate this you should divide 100 MHz by (100M / 38400) = 2604.16666...
The error you get by rounding this to the nearest integer is small.
Dividing by 2604 will give you the baudrate 2400.15
That is OK.
A baudrate difference between transmitter and receiver of up to about 1-2% is probably OK.
In some situations with a slower clock and higher baudrate it can be impossible to find an integer divisor which is close enough. You can then use a fractional divider which will give jitter on the transmitted data, but that is normally acceptable.

If you design your own UART you can have the clock different from 16 times the baudrate. It is the receiver that needs a clock higher than the baudrate.The minimum clock frequency is 3 times the baudrate. The transmitter can have a clock frequency identical to the baud rate.
 

Why should we multiple with 16 only ?

what is logic using 16 here .
 

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