GMS81508B HYNIX [Hynix Semiconductor], GMS81508B Datasheet - Page 58

• Manufacturer Part Number: GMS81508B
• Description: HYUNDAI MICRO ELECTRONICS 8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: HYNIX [Hynix Semiconductor]

HYUNDAI MicroElectronics
15. BUZZER FUNCTION
The buzzer driver block consists of 6-bit binary counter,
buzzer register, and clock source selector. It generates
square-wave which has very wide range frequency (500Hz
~ 250kHz at f
A 50% duty pulse can be output to R55/BUZ pin to use for
piezo-electric buzzer drive
of Buzzer driver by setting the bit 5 of PMR5 (address D1
“1”.
mode (the bit 5 of R5DD=1).
Example: 2.4kHz output at 8MHz.
X means don’t care
DEC. 1999 Ver 1.04
At this time, the pin R55 must be defined as output
PMR5
XIN PIN
LDM
LDM
LDM
XIN
-
= 8MHz) by user software.
-
R5DD,#XX1X_XXXXB
BUR,#9AH
PMR5,#XX1X_XXXXB
W
. Pin R55 is assigned for output port
W
-
128
16
32
64
ADDRESS: 0D1
RESET VALUE: --00 ----
R54/WDTO Selection
0: R54
1: WDTO (Output)
R55/BUZ Selection
0: R55 port (Turn off buzzer)
1: BUZ port (Turn on buzzer)
MUX
-
Figure 15-1 Block Diagram of Buzzer Driver
00
01
10
11
-
Figure 15-2 PMR5 and Buzzer Register
2
[0EC
-
H
]
H
6-bit binary
6-BIT COUNTER
BUR
Internal bus line
Compare data
H
B
) to
6
Comparator
R55 port data
BUR
The bit 0 to 5 of BUR determines output frequency for
buzzer driving.
Equation of frequency calculation is shown below.
f
f
Divide Ratio: Prescaler divide ratio by BUCK[1:0]
BUR: Lower 6-bit value of BUR. Buzzer period value.
The frequency of output signal is controlled by the buzzer
control register BUR.The bit 0 to bit 5 of BUR determine
output frequency for buzzer driving.
BUZ
XIN
: Oscillator frequency
: Buzzer frequency
BUCK1 BUCK0
W
F/F
2
W
W
[0D1
f
BUZ
H
0
1
W
]
PMR5
=
-------------------------------------------------------------
2
W
DivideRatio
ADDRESS: 0EC
RESET VALUE: Undefined
Port selection
W
BUR[5:0]
Buzzer Period Data
Source clock select
00: 16
01:
10:
11: 128
GMS81508B/16B/24B
f
XIN
W
32
64
R55/BUZ PIN
W
BUR
H
55