Preliminary Information
MT8843
TIP/RING
1st Ring
A
B
Ch. seizure
C
Mark
D
Data Packet
E
F
2nd Ring
TRIGout
Note 4
PWDN
Note 1
Note 3
Note 1
OSCout
FSKen
Note 2
t
CP
t
CA
CD
DR
DCLK
..101010..
A = 2sec typical
B = 250-500ms
C = 250ms
D = 150ms
E = feature specific
Max C+D+E = 2.9 to 3.7sec
F
≥
200ms
Data
DATA
Figure 17 - Input and Output Timing for Bellcore On-hook Data Transmission Associated with
Ringing, e.g., CID
Notes:
This on-hook case application is included because a CIDCW (off-hook) CPE should also be capable of receiving on-hook data
transmission (with ringing) from the end office. TR-NWT-000575 specifies that CIDCW will be offered only to lines which subscribe to
CID.
1) The CPE designer may choose to enable the CNIC2 only after the end of ringing to conserve power in a battery operated CPE. CD is not
activated by ringing.
2) The CPE designer may choose to set FSKen always high while the CPE is on-hook. Setting FSKen low prevents the FSK
demodulator from reacting to other in-band signals such as speech, CAS or DTMF tones.
3) The microcontroller in the CPE powers down the CNIC2 after CD has become inactive.
4) The microcontroller times out if CD is not activated.
5-39
MITEL [ MITEL NETWORKS CORPORATION ]
