HD404889_03 Datasheet, PDF (147/197 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 Series
Port mode register 2 (PMR2: $00A):
Port mode register 2 (PMR2) is a 4-bit write-only register used to switch the R1₂/BUZZ pin function as
shown in figure 30.
Port mode register 2 (PMR2) is reset to $0 by an MCU reset.
BUZZ
Timer B
overflow
Timer C
overflow
1/2
(toggle)
φ_PER
1/2
1/3
1/4
Synchro-
nization
circuit
Data bus
Clock line
Signal line
Buzzer
mode
register
Figure 93 Buzzer Output Circuit
Rev.6.00, Sep.08.2003, page 147 of 197