Digi NS9215 - Manual (Page 387)

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S E R I A L C O N T R O L M O D U L E : U A R T
Baud rate generator
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B a u d r a t e g e n e r a t o r
The baud rate clock is generated by dividing the system reference clock by a
programmable divisor; use this formula:
BR = CLK
ref
/ (BRD x 16)
The default reference clock for the UARTs is the system reference clock input on
x1_sys_osc. The UART reference clock optionally can be input on GPIO_A[3].
Baud rates
This table shows the baud rates achieved with CLK
ref
set to 29.4912:
UART Interrupt Enable register
(0x104) ETBEI 0x1 Enable the Transmitter Holding
Register Empty Interrupt. enables the
Wrapper to write a transmit character
to the UART.
Wrapper Configuration register TX FLOW
Software 1 TX Enabled
RXEN 1 Enable Wrapper receive function
TXEN 1 Enable Wrapper transmit function
Control register Field Value Comment
Divisor Baud rate
1 1,843,299
2 921,600
4 460,800
8 230,400
16 115,200
32 57,600
48 38,400
64 28,800
96 19,200
128 14,400
192 9,600
384 4,800
768 2,400