Uart1 Baud Rate - Fujitsu MB90895 Series Hardware Manual

15.5

UART1 Baud Rate

One of the following can be selected as the UART1 transmit/receive clock.
• Dedicated baud rate generator
• Internal clock (16-bit reload timer output)
• External clock (clock input to SCK1 pin)
I Select of UART1 Baud Rate
The UART1 baud rate select circuit comprises as shown in .The clock input source can be selected from
among the following three types:
G
Baud rate by dedicated baud rate generator
• When using the dedicated baud rate generator incorporated into UART1 as a clock input source, set the
CS2 to CS0 bits in the serial mode register (SMR1) to "000
baud rate can be selected from six types.
G
Baud rate by internal timer
• When using the internal clock supplied from the 16-bit reload timer as a clock input source, set the CS2
to CS0 bits in SMR1 bit 5 to 3 to "110
• The baud rate is the value at which the frequency of the clock supplied from the 16-bit reload timer as it
is in the clock synchronous mode, and the value at which the frequency of the supplied clock is divided
by 16 in the clock asynchronous mode.
• Any baud rate can be selected according to the setting values of the 16-bit reload timer.
G
Baud rate by external clock
• When using the external clock supplied from the clock input pin (SCK1) in the UART1 as the clock
input source, set the CS2 to CS0 bits in SMR1 bit 5 to 3 to "111
• The baud rate is the value at which the external clock is supplied in the clock synchronous mode and the
value at which the frequency of the input clock is divided by 16 in the clock asynchronous mode.
" to "101
B
".
B
B
CHAPTER 15 UART1
" according to the baud rate.The
B
".
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