Fujitsu MB90390 Series, Hardware Manual

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CHAPTER 20 UART2, UART3
20.4.7 Baud Rate Generator Register 0 and 1 (BGR02/03 and
BGR12/13)
The baud rate generator registers 0 and 1 (BGR02/03 and BGR12/13) set the division
ratio for the serial clock. Also the actual count of the transmission reload counter can
be read.
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Bit Configuration of Baud Rate Generator Register (BGR02/03 and BGR12/13)
Figure 20.4-8 shows the bit configuration of the baud rate generator register (BGR02/03 and BGR12/13).
Figure 20.4-8 Bit Configuration of Baud Rate Generator Register (BGR02/03 and BGR12/13)
The baud rate generator register sets the division ratio of the serial clock. The BGR12/13 and BGR02/03
correspond to the upper byte and lower byte, respectively, and writing of counter reload value and reading
of transmission reload counter value is allowed.
Also, both registers can be read or written via byte or word access.
When writing reload value other than "0" to baud rate generator register, the reload counter starts counting.
15 b it 14 1 3 12 11 10 9 8 7 6 5 4 3 2 1 0
Initi a l v a l u e
0 0 0 0 0 0 0 0
B
R/W R/W R/W R/W R/W R/W R/W
b it7 to b it0
BGR7 to BGR0
B au d r a te Gener a tor Regi s ter 02,0 3
write Write b it 7 to 0 of relo a d v a l u e to co u nter
re a d Re a d b it 7 to 0 of tr a n s mi ss ion relo a d co u nter
b it14 to b it 8
BGR14 to BGR 8
B au d r a te Gener a tor Regi s ter 12,1 3
write Write b it 14 to 8 of relo a d v a l u e to co u nter
re a d Re a d b it 14 to 8 of tr a n s mi ss ion relo a d co u nter
b it15
Undefined b it
"0" i s re a d.
R/W : Re a d ab le a nd writ ab le
R
-
: Re a d onl
:
y
R/W R/W R/W R/W R/W R/W R/W R/W
0 0 0 0 0 0 0 0
B
BGR0 3 : 00 3 51E
H
BGR1 3 : 00 3 51F
H
Addre ss :
R
re a d
BGR02: 00 3 5DE
H
BGR12: 00 3 5DF
H
Undefined b it