
CHAPTER 6 CLOCK GENERATION FUNCTION
User’s Manual U15905EJ2V1UD
210
6.5.1
Control register
(1) Prescaler mode register (PRSM)
The PRSM register controls generation of the clock of the watch timer and A/D converter.
This register can be read or written in 8-bit or 1-bit units.
0
PRSM
0
CE
0
TODIS
BGCS1
BGCS0
Fixed to 0
Operates
Fixed to 0
CE
0
1
TODIS
X
0
1
Baud rate output
Fixed to 0
Operates
Baud rate interrupt signal (INTBRG)
fX
fX/2
fX/4
fX/8
10 MHz
100 ns
200 ns
400 ns
800 ns
4 MHz
250 ns
500 ns
1 s
2 s
BGCS1
0
1
BGCS0
0
1
0
1
Selects input clock (fBRGS)
After reset: 00H
R/W
Address: FFFFF8B0H
Cautions 1. Do not change the values of BGCS1 and BGCS0 during transmission/reception.
2. Set the PRSM register before setting the CE bit to 1.
3. Set the PRSM and PRSCM registers in accordance with the main clock frequency to be
used, so that the frequency of fBRG is 32.768 kHz.