Panasonic EB-GD30, Техническое руководство

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BASEBAND OVERVIEW
MCUK991001G8 Section 6 Issue 1
Technical Guide – 25 – Revision 0
6.2.11 Buzzer
The volume level of the buzzer is defined by the 6 bit PWM register setting in GEMINI I/O. The buzzer tone is then
superimposed on this level using software.
Timer 1 in GEMINI is used to time the period between switching the buzzer on and off to make the tone. For more complex
buzzer ringing tones, the buzzer volume level can also be altered after each time-out of Timer 1.
Figure 6.10: Buzzer Control Circuit
6.2.12 Timers
The two 16 bit general purpose timers can be used either as auto-reload or one-shot timers to provide interrupts to the
ARM CPU. A prescaler and 16 bit register define the timer clock duration. The Timer unit receives a 928 kHz clock signal from
the GEMINI clock module. A combination of the prescaler and timer register gives a time range of 1.078 µs to 9.039 s.
6.2.13 USART
The serial port is compatible with an Intel 8251 and has six pins.
Timer Function Setting
1 Buzzer Timer Tone frequency
2 Watch Dog Timer 40 ms
USART Pin Assignments
Signal Name Pin No. Function I/O
TXD 113 UART serial data Tx O
RXD 111 UART serial data Rx I
DTR 114 Used as I/O pin O
DSR 110 Used as I/O pin I
TXE 115 Used as I/O pin O
RXE 116 Used as I/O pin O
VBAT
GEMINI
U503
CHARGING ASIC
U401
BUZZER
LS900
10148-1
BU
120
BUZZ
22
BUZZOUT
19