ds21ft40 Maxim Integrated Products, Inc., ds21ft40 Datasheet - Page 36

• Manufacturer Part Number: ds21ft40
• Description: Ds21ft40 Four X Three 12 Channel E1 Framer
• Manufacturer: Maxim Integrated Products, Inc.

CRC4 SYNC COUNTER
The CRC4 Sync Counter increments each time the 8 ms CRC4 multiframe search times out. The counter
is cleared when the framer has successfully obtained synchronization at the CRC4 level. The counter can
also be cleared by disabling the CRC4 mode (CCR1.0=0). This counter is useful for determining the
amount of time the framer has been searching for synchronization at the CRC4 level. ITU G.706 suggests
that if synchronization at the CRC4 level cannot be obtained within 400 ms, then the search should be
abandoned and proper action taken. The CRC4 Sync Counter will rollover.
SR1: STATUS REGISTER 1 (Address=06 Hex)
(MSB)
RSA1
SYMBOLS
RDMA
RSLIP
RUA1
RLOS
RSA1
RSA0
RRA
RCL
RDMA
POSITION
SR1.7
SR1.6
SR1.5
SR1.4
SR1.3
SR1.2
SR1.1
SR1.0
RSA0
NAME AND DESCRIPTION
Receive Distant MF Alarm. Set when bit–6 of timeslot 16 in
Receive Remote Alarm. Set when a remote alarm is received
Receive Carrier Loss. Set when 255 (or 2048 if CCR3.0=1)
Receive Signaling All Ones / Signaling Change. Set when
over a full MF, the content of timeslot 16 contains less than
three zeros. This alarm is not disabled in the CCS signaling
mode. A change in the contents of RS1 through RS16 from
one multiframe to the next will cause RSA1 and RSA0 to be
set.
frame 0 has been set for two consecutive multiframes. This
alarm is not disabled in the CCS signaling mode.
Receive Signaling All Zeros / Signaling Change. Set when
over a full MF, timeslot 16 contains all zeros. A change in the
contents of RS1 through RS16 from one multiframe to the next
will cause RSA1 and RSA0 to be set.
Receive Side Elastic Store Slip. Set when the elastic store has
either repeated or deleted a frame of data.
Receive Unframed All Ones. Set when an unframed all ones
code is received at RPOS and RNEG.
at RPOS and RNEG.
consecutive zeros have been detected at RPOS and RNEG.
Receive Loss of Sync. Set when the device is not
synchronized to the receive E1 stream.
RSLIP
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RUA1
RRA
RCL
RLOS
(LSB)
DS21FT40