E0C5250
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E0C5250 Timing Chart
Bellcore on-hook data transfer
INP/INN
#RDRC
#IRQ
PDWN
MODE
Ring detection
Power-down
after receiving last data
Power-down due to timeout
1st RING
FSK
data transfer
2nd RING
FSK/read mode
Ring detection
Carrier detection
No carrier
#DET
SDI
Receive data
SDO
Serial clock
#SCLK
OSC4
Bellcore off-hook data transfer
CPE→Off-Hook
CPE→Receiver muted
CPE→Receiver muting released
INP/INN
#RDRC
#IRQ
PDWN
MODE
#DET
SDI
SDO
SAS
CAS
ACK
FSK data transfer
DTMF D transmitted from CPE
Power-on state maintained when receiver
is off-hook to detect CAS tone
CAS/write mode
CAS tone detection
Control data bits written
Placed in CAS mode
after receiving last data
FSK/read mode
Carrier detection
FSK mode must be set to prevent failure in carrier detection after sending ACK
Receive data
Serial clock
Serial clock
#SCLK
OSC4
9
SEIKO [ SEIKO EPSON CORPORATION ]
