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DS21354 & DS21554
48 of 117
CCR5: COMMON CONTROL REGISTER 5 (Address=AA Hex)
[Repeated here from section 6 for convenience]
(MSB)
(LSB)
LIRST
RESALGN
TESALGN
RCM4
RCM3
RCM2
RCM1
RCM0
SYMBOL
POSITION
NAME AND DESCRIPTION
LIRST
CCR5.7
Line Interface Reset.
RESALGN
CCR5.6
Receive Elastic Store Align.
TESALGN
CCR5.5
Transmit Elastic Store Align.
RCM4
CCR5.4
Receive Channel Monitor Bit 4.
MSB of a channel decode that deter-
mines which receive channel data will appear in the RDS0M register. See
Section 9 for details.
RCM3
CCR5.3
Receive Channel Monitor Bit 3.
RCM2
CCR5.2
Receive Channel Monitor Bit 2.
RCM1
CCR5.1
Receive Channel Monitor Bit 1.
RCM0
CCR5.0
Receive Channel Monitor Bit 0.
LSB of the channel decode.
RDS0M: RECEIVE DS0 MONITOR REGISTER (Address=AB Hex)
(MSB)
(LSB)
B1
B2
B3
B4
B5
B6
B7
B8
SYMBOL
POSITION
NAME AND DESCRIPTION
B1
RDS0M.7
Receive DS0 Channel Bit 1.
MSB of the DS0 channel (first bit received).
B2
RDS0M.6
Receive DS0 Channel Bit 2.
B3
RDS0M.5
Receive DS0 Channel Bit 3.
B4
RDS0M.4
Receive DS0 Channel Bit 4.
B5
RDS0M.3
Receive DS0 Channel Bit 5.
B6
RDS0M.2
Receive DS0 Channel Bit 6.
B7
RDS0M.1
Receive DS0 Channel Bit 7.
B8
RDS0M.0
Receive DS0 Channel Bit 8.
LSB of the DS0 channel (last bit received).
10 SIGNALING OPERATION
The DS21354/554 contains provisions for both processor based (i.e., software based) signaling bit access
and for hardware based access. Both the processor based access and the hardware based access can be
used simultaneously if necessary. The processor based signaling is covered in Section 10.1 and the
hardware based signaling is covered in Section 10.2. When referring to signaling, the Voice Channel
numbering scheme is used.
10.1 Processor Based Signaling
The Channel Associated Signaling (CAS) bits embedded in the E1 stream can be extracted from the
receive stream and inserted into the transmit stream by the framer. Each of the 30 voice channels has four
signaling bits (A/B/C/D) associated with it. The numbers in parenthesis () are the voice channel
associated with a particular signaling bit. The voice channel numbers have been assigned as described in
the ITU documents. Please note that this is different than the channel numbering scheme (1 to 32) that is
used in the rest of the data sheet.