MT8841
TIP/RING
PWDN
2 sec
channel seizure Mark state
checksum
First Ringing
500ms
(min)
Input FSK
Data
200ms
(min)
Second
Ringing
OSC2
CD *
DATA
tPU
tIAL
High (Input Idle)
tPD
tIAH
High (Input Idle)
DCLK
DR *
* with external pull-up resistor
Figure 9 - Input and Output Timing (Bellcore CND Service)
TIP/RING
DATA
start
stop
start
stop
start
stop
b7 1 0 b0 b1 b2 b3 b4 b5 b6 b7 1 0 b0 b1 b2 b3 b4 b5 b6 b7 1 0 b0 b1 b2
tIDD
start
b7
stop
b0 b1 b2 b3 b4 b5 b6 b7
start
b0 b1 b2 b3 b4 b5 b6 b7
stop
start
b0 b1 b2
stop
DCLK
DR *
tCRD
* with external pull-up resistor
Figure 10 - Serial Data Interface Timing
5-19