Datasheet
13
UNI-DS6
MikroElektronika
page
9. Piezo buzzer
Due to a built-in piezo buzzer, the UNI-DS6 development system is capable of emitting audio signals� In order to enable
the piezo buzzer to operate properly it is necessary to generate a voltage signal of specic frequency. Remember, when
writing code for voltage signal generation, that the piezo buzzer’s resonant frequency is 3�8kHz� Other frequencies in
the range between 20Hz and 20kHz can also be used, but the best performance is provided with frequencies ranging
between 2kHz and 4kHz� To establish connection between the piezo buzzer and the microcontroller, it is necessary to
place jumper J14 in adequate position� If jumper J14 is placed in the RC1 position the RC1 MCU pin is used for signal
generation, Figure 9-2� Otherwise place jumper J14 in the RA4 position in order to use the RA4 MCU pin for signal
generation, Figure 9-3�
VCC-5V
BUZZER
R22
PZ1
10K
R23
1K
Q1
BC846
RC1
RA4
J14
RA4 RE4
RE2
RA12
RB4 RF12
RB12 RG4
RC4 RG12
RC12 RH4
RD4 RJ4
RD12
USB-VBUS
RA6
RA14 RF6
RB6 RF14
RB14 RG6
RC6 RG14
RC14 RH6
RD6 RJ6
RD14
#RX232A
#TX232A
#SCL
#SDA
#SS1#
#SCK1
#MISO1
#MOSI1
USB-DP
RA0 RE0
RA8 RF0
RE6
RB0 RF8
RB8 RG0
RC0 RG8
RC8 RH0
RD0 RJ0
RD8
RA2
RA10 RF2
RF4
RB2 RF10
RB10 RG2
RC2 RG10
RC10 RH2
RD2 RJ2
RD10
RA5
RA13
RB5 RF13
RB13 RG5
RC5 RG13
RC13 RH5
RD5 RJ5
RD13
RA7
RA15 RF7
RF5
RF3
RB7 RF15
RB15 RG7
RC7 RG15
RC15 RH7
RD7 RJ7
RD15
#RX232B
#TX232B
#CS1#
#CS2#
#SS2#
#SCK2
#MISO2
#MOSI2
USB-DN
RA1 RE1
RA9 RF1
RE7
RE5
RE3
RB1 RF9
RB9 RG1
RC1 RG9
RC9 RH1
RD1 RJ1
RD9
RA3
RA11
RB3 RF11
RB11 RG3
RC3 RG11
RC11 RH3
RD3 RJ3
RD11
VCC-SW VCC-5V
CN20 CN21
Figure 9-4: Piezo buzzer connection schematic
Figure 9-1: Piezo buzzer
Figure 9-3: Signal generation via RA4Figure 9-2: Signal generation via RC1