
425
Chapter 12
Asynchronous Serial Interface A (UARTA)
User’s Manual U16702EE3V2UD00
12.6 Dedicated Baud Rate Generator
The dedicated baud rate generator consists of a source clock selector and 8-bit programmable
counters, and generates a serial clock for transmission/reception by UARTAn. The output of the dedi-
cated baud rate generator can be selected as the serial clock on a channel by channel basis.
8-bit counters are provided separately for transmission and reception.
(1)
Configuration of baud rate generator
Figure 12-16:
Configuration of Baud Rate Generator
Remarks: 1.
n = 0 to 1
2.
f
XX
: Internal system clock
(a) Base clock
The clock selected by the UAnCKS3 to UAnCKS0 bits of the UAnCTL1 register is supplied to the
8-bit counter when the UAnPWR bit of the UAnCTL0 register is 1. This clock is called the base
clock, and its frequency is called f
XCLK
. When the UAnPWR bit is 0, the base clock is fixed to the
low level.
(b) Generation of serial clock
A serial clock can be generated in accordance with the setting of the UAnCTL1 and UAnCTL2 reg-
isters (n = 0 to 1).
The base clock is selected by using the UAnCKS3 to UAnCKS0 bits of the UAnCTL1 register.
The division ratio of the 8-bit counter can be selected by using the UAnBRS7 to UAnBRS0 bits of
the UAnCTL2 register.
Clock
(f
XCLK
)
Selector
UAnPWR
8-bit counter
Match detector
Baud rate
UAnCTL2:
UAnBRS7 to UAnBRS0
1/2
UAnPWR, UAnTXEn (or UAnRXE)
UAnCTL1:
UAnCKS3 to UAnCKS0
f
XX
f
XX
/2
f
XX
/4
f
XX
/8
f
XX
/16
f
XX
/32
f
XX
/64
f
XX
/128
f
XX
/256
f
XX
/512
f
XX
/1024
ASCKAn
electronic components distributor
Содержание V850E/RS1
Страница 6: ...6 User s Manual U16702EE3V2UD00 Downloaded from Elcodis com electronic components distributor...
Страница 206: ...206 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 232: ...232 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 366: ...366 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 402: ...402 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 684: ...684 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 766: ...766 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 798: ...798 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 832: ...832 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 834: ...834 User s Manual U16702EE3V2UD00 MEMO Downloaded from Elcodis com electronic components distributor...
Страница 848: ...848 User s Manual U16702EE3V2UD00 Downloaded from Elcodis com electronic components distributor...
Страница 852: ...Downloaded from Elcodis com electronic components distributor...