GMS87C4060 Datasheet, PDF (55/102 Pages) Hynix Semiconductor – 8-BIT SINGLE-CHIP MICROCONTROLLERS

PRELIMINARY
GMS81C4040/87C4060
16. Buzzer driver
The Buzzer driver circuit is shown in Figure 16-1 .
The Buzzer driver circuit consists of the 6bit counter, 6bit
comparator, Buzzer data register BUR(00EE_H). The BUR
register controls source clock and output frequency.
The more details about registers are shown Figure 16-2 .
BUR [EE_H]
BUCK BUCK
-1
-0
BU5 BU4
BU3
BU2
BU1 BU0
6
PS4
00
PS5
01
PS6 ₁₀
PS7 ₁₁
MUX
6bit Comparator
clear
6
6bit counter
clear
PWMCR2 [EB_H]
BUZS
POL2 POL1 EN7 EN6
BUR write
Output
Generator
BUZZ
Figure 16-1 Block Diagram of Buzzer driver circuit
Control
The GMS81C4040/GMS87C4060 contains a Buzzer driv-
er module.
1. Select an input clock among PS4~7 by set the
BUCK1~0 of BUR.
BUCK1
0
0
1
1
BUCK0
0
1
0
1
Clock source
PS4
PS5
PS6
PS7
2. Select output frequency by change the BU5~0.
Output frequency = 1 / (PSx * BUy *2) Hz.
x=4~7, y=5~0
See example Table 16-1 and Table 16-2.
Note: Do not select 00_H to BU5~0. It means counter stop.
3. Set BUZS bit for output enable.
4. Output waveform is rectagle clock which has 50% duty.
5. You can use this clock for the other purposes.
Buzzer data Register
ADDRESS : 0EE_H
RESET VALUE : ???? ????_b
W
W
W
W
W
W
W
W
BUR
BUCK BUCK
-1
-0
BU5 BU4
BU3
BU2
BU1 BU0
Input select
Clock Select
PWM control Register 2
PWMCR2
RW
BUZS
ADDRESS : 0EB_H
RESET VALUE : --0- 00--_b
RW RW
POL2 POL1
R50/Buzz select
0: R50
1: Buzz output
Figure 16-2 Buzzer driver Registers
Nov. 1999 Ver 1.0
PRELIMINARY
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