EM91401 SERIES
TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE
AND DUAL-TONE MELODY GENERATOR
SDO (Serial Data Output) function
The SDO is serial data output which format is same as UART protocol. SDO function is designed to drive LCD
driver and voice synthesizer. So the dialing numbers can be display on LCD screen with EM32100 (or EM32116
). The SDO signal consists of two start bits, six data bits and two stop bits. Each bit time is about 3.9 ms (256 Hz)
and output sequences are following by start bits, data bits (LSB to MSB) and stop bits.
1
0
1
bit 0
bit2
data bits
bit3
bit4
bit5
0
bit1
stop bits
start bits
ready
SDO Keypad Encoded table:
♦ Digital key (b5,b4=0,0)
keypad
output
1
2
3
4
5
6
7
8
9
0
“*”/T
#
P
*/”T”
b3,b2,b1,b0 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110
Display
1
2
3
4
5
6
7
8
9
0
P
♦ Function key (b5,b4=1,0)
keypad
F
output
b3,b2,b1,b0
Display
1111
clear all display
Keypad,SDO format and LCD display reference table:
Keypad
bit5
bit4
bit3
bit2
bit1
bit0
Display
1
0
0
0
0
0
1
1
2
3
4
5
6
7
8
9
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
1
1
1
1
0
0
0
0
1
1
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
2
3
4
5
6
7
8
9
0
0
“*”/T
#
P
P
*/”T”
F
clear all display
LOCK function
The EM91401 serial provides the LOCK function to inhibit toll dialing operation. Connecting a resistor on COL1
* This specification are subject to be changed without notice.
10.1.1997
8
ELAN [ ELAN MICROELECTRONICS CORP ]
