w925e625 ETC-unknow, w925e625 Datasheet - Page 66

• Manufacturer Part Number: w925e625
• Description: 8-bit Cid Microcontroller
• Manufacturer: ETC-unknow

Notes:
1. In a CPE where AC power is not available, the designer may choose to switch over to line power when the CPE goes
2. The FSKE bit may be set low to prevent the alert tone, speech or other FSK in-band noise decoded by FSK
3. The exchange will have already disabled the speech path to the distant customer in both transmission directions.
4. The FSKE should be set high as soon as the CPE has finished sending the acknowledge signal ACK.
5. The FSKE may be set low after the last byte (check sum) has been decoded or FCD has become inactive.
6. In an unsuccessful attempts where the exchange does not send the FSK signal, the CPE should disable FSKE, un-mute
Tip/Ring
FDATA
ALGO
off-hook and use battery power while on-hook.
demodulator and give false data when the dual tone alert signal is expected. If the FSKE pin can not controlled by
micro-controller, the FSKE bit must always placed in high state and the micro controller must give up the FSK decoded
data when the FSK signal is not expected.
the handset and enable the keypad after this interval.
FSKE
FCLK
CIDF
ASE
FCD
FDR
Note 1
CPE goes off-hook
Note 2
t REC
Note 3
Figure 6-30 Input and Output Timing of BT Loop State (Off-hook) Data Transmission
Start Point
A
CAS
B
CPE mutes handset & disables keypad
C
t ABS
CPE sends
ACK
D
Note 4
E
- 66 -
Mark
F
Message
Data
...
...
G
CPE unmutes handset and
Note 5
A = 40 - 50mS
B = 80 - 85mS
C <= 100mS
D = 65 - 75mS
E = 5 - 100mS
F = 40 - 75mS
G = depends on data length
H <= 100mS
H
enable keypad
W925E/C625