EM6605 EM Microelectronic, EM6605 Datasheet - Page 16

• Manufacturer Part Number: EM6605
• Description: 4 bit Microcontroller
• Manufacturer: EM Microelectronic

7. BUZZER
The EM6605 has one 50% duty cycle output with three different frequencies which can be used to drive a
buzzer. I/O terminal PB0 is used for this function when the buzzer is enabled by setting the BUen bit to 1 .
Table 23 below shows how to select the frequency by writing to the BCF1 and BCF0 control flags in the
BEEP register.
After writing to the buzzer control register BEEP, the chosen frequency (or silence) is selected
immediately. With the BUen bit set to 1, the selected frequency is output at PB0. When the BUen is set
to 0 PB0 is used as a normal I/O terminal of PortB. The BUen bit has a higher priority over the I/O
control bit CIOPB0 in the CIOPortB register.
Table 23.Buzzer frequency selection
7.1. Buzzer Register
Table 24.Buzzer control register - BEEP
© EM Microelectronic-Marin SA, 02/99, Rev. B/243
16
Tone frequency
silence
ck[buz1] = ck[11] or ck[8] by metal option (1024 Hz *f1)
ck[buz2] = ck[12] or ck[10] by metal option (2048 Hz *f1)
ck[buz3]
Bit
3
2
1
0
Name
TimEn
BUen
BCF1
BCF0
Reset
0
0
0
0
(2667 Hz *f1)
R/W
R/W
R/W
R/W
R/W
Timer/counter enable
Buzzer enable
Buzzer Frequency control
Buzzer Frequency control
Description
BCF1
0
0
1
1
BCF0
0
1
0
1
EM6605