W925EP01 Datasheet, PDF (63/108 Pages) Winbond – 8-BIT CID MICROCONTROLLER

W925EP01/ W925EP01FG
6.12 FSK Generator
W925EP01 provides a FSK generator, which outputs the FSK signal to the DTMF pin. The FSK output
share with DTMF output pin. It can out FSK signal with 1200Hz baud rate of ITU-T V.23 or Bellcore
202 signal. A FSK transmit data register (FSKTB) specifies the desired output data. The FSK Transmit
Control Register (FSKTC) can control whether the FSK signal will be output or not. The relation timing
is shown in Figure 6-10
Enable signal
(FTE)
Latch clock
[FSF]
Data latch Flag
(FDS)
Data
(FSKTB) bit0
Interrupt occur when rising edge
Auto clear
101100
FSK Signal
(DTMF pin)
Hi-Z
1 01 1
833us
Figure 6-10 FSK Modulator
Hi-Z
0
FSK TRANSIMT CONTROL REGISTER
Bit:
7
6
5
4
FTE FTM FDS
-
Mnemonic: FSKTC
FTE: FSK transmit Enable. Enable=1, Disable=0
FTM: FSK signal Standard. Bellcore 202=1, V.23=0
FDS: FSK data sending status
LO0, LO1: FSK transmitting level option
(initial=00H)
3
2
1
0
-
-
LO1 LO0
Address: C6h
FSK output level
LO1
LO0
150mV
0
0
125mV
0
1
100mV
1
0
75mV
1
1
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Publication Release Date: Apr. 10, 2006
Revision A2