em78p811 ELAN Microelectronics Corp, em78p811 Datasheet - Page 27

• Manufacturer Part Number: em78p811
• Description: 8-bit Micro-controller
• Manufacturer: ELAN Microelectronics Corp

* RB ( DTMF Register )
. Bit 0 - Bit 3 are row-frequency tone.
. Bit 4 - Bit 7 are column-frequency tone.
. Initial RB is equal to HIGH.
. Except below values of RB ,the other values of RB are not effect. If RB is set by ineffective value, the DTMF output
will be disable and there is no tone output.
. Bit 7 ~ 0 are all "1" , turn off DTMF power .
VII.11 LCD Driver
totally. LCD block is made up of LCD driver , display RAM, segment output pins , common output pins and LCD
operating power supply pins.
register . LCD control register.
timing for different duty and display access. RE register is a command register for LCD driver, the LCD display( disable,
enable, blanking) is controlled by LCD_C and the driving duty and bias is decided by LCD_M and the display data is
stored in data RAM which address and data access controlled by registers RC and RD.
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* This specification is subject to be changed without notice.
bit 3~0
1110
1101
1011
0111
Column freq
bit 7~4
The CALLER ID IC can drive LCD directly and has 60 segments and 16 commons that can drive 60*16 dots
Duty , bias , the number of segment , the number of common and frame frequency are determined by LCD mode
The basic structure contains a timing control which uses the basic frequency 32.768KHz to generate the proper
Row freq
699.2Hz
771.6Hz
854Hz
940.1Hz
ROW
Register
COLUMN
Register
1
4
7
*
1203Hz
1110
SYSTEM CLOCK
Fig17. DTMF Block Diagram
DTMF high-freq
selection
DTMF low-freq
selection
Low frequency generator
High frequency generator
2
5
8
0
1331.8Hz
1101
26
3
6
9
#
1472Hz
1011
Sine wave
generator
Sine wave
generator
A
B
C
D
1645.2Hz
0111
Adder
DTMF tone
output
8-bit OTP Micro-controller
EM78P811