em91415 ELAN Microelectronics Corp, em91415 Datasheet - Page 8

• Manufacturer Part Number: em91415
• Description: Tone/pulse Switchable Dialer With Lcd Interface And Dual-tone Melody Generator Tone/pulse Switchable Dialer With Lcd Interface And Dual-tone Melody Generator
• Manufacturer: ELAN Microelectronics Corp

* This specification are subject to be changed without notice.
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.
Operating flow chart
Truth table
Music on Hold
EM91415 series built-in a melody generator to generate dual-tone music on DTMF output pin. The music is
designed for telephone line at line holding.
<Note> : HF = Handfree
(0) On-hook, idle state
(1) Off-hook line
(2) Off-hook, HF line
(3) On-hook, HF line
(4) Off-hook, HD line
(5) On-hook, HD line
Note : F=floating (high impedance); H=logic “High”; L=logic “Low” level.
Operating state
HD = Hold
HD
HD
Hold-line State
Hand-free State
On-hook
On-hook
6
4
HF
HF
HKS=Hi
HF
HKS
H
H
H
L
L
L
HKS=Hi
HKS=Lo
Hand-free State
On-hook State
TONE/PULSE SWITCHABLE DIALER WITH LCD INTERFACE
HKS=Lo
Off-hook
1
3
F
F
F
F
F
F
PO
HD
Input/Output pin level
HF
XMUTE
HKS=Hi
HF
HKS=Lo
HF
F
F
F
F
L
L
AND DUAL-TONE MELODY GENERATOR
Hold-line State
Off-hook State
Off-hook
HD
5
2
HFO
HD
H
H
L
L
L
L
EM91415 SERIES
HDO
H
L
L
L
L
H
10.1.1997
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