IDT82P2282
DUAL T1/E1/J1 LONG HAUL / SHORT HAUL TRANSCEIVER
75
August 20, 2009
Figure 27. E1 To T1/J1 Format Mapping - Continuous Channels Mode
In the Transmit Clock Slave mode, the timing signal on the TSCKn
pin and the framing pulse on the TSFSn pin to input the data on the
TSDn pin are provided by the system side. When the TSLVCK bit is set
to ‘0’, each link uses its own TSCKn and TSFSn; when the TSLVCK bit
is set to ‘1’ and both two links are in the Transmit Clock Slave mode, the
two links use the TSCK[1] and TSFS[1] to input the data. The signaling
bits on the TSIGn pin are per-channel aligned with the data on the TSDn
pin.
In the Transmit Clock Slave mode, the data on the system interface
is clocked by the TSCKn. The active edge of the TSCKn used to sample
the pulse on the TSFSn is determined by the FE bit. The active edge of
the TSCKn used to sample the data on the TSDn and TSIGn is deter-
mined by the DE bit. If the FE bit and the DE bit are not equal, the pulse
on the TSFSn is ahead. The data rate of the system side is 1.544 Mb/s
or 2.048 Mb/s. When it is 2.048 Mb/s, the TSCKn can be selected by the
CMS bit to be the same rate as the data rate on the system side (2.048
MHz) or double the data rate (4.096 MHz). If both two links use the
TSCK[1] and TSFS[1] to input the data, the CMS bit of the two links
should be set to the same value. If the speed of the TSCKn is double the
data rate, there will be two active edges in one bit duration. In this case,
the EDGE bit determines the active edge to sample the data on the
TSDn and TSIGn pins. The pulse on the TSFSn pin is always sampled
on its first active edge.
In the Transmit Clock Slave mode, the TSFSn can indicate each F-
bit or the first F-bit of every SF/ESF/T1 DM/SLC-96 multi-frame. The
indications are selected by the FSTYP bit. The active polarity of the
TSFSn is selected by the FSINV bit. If the pulse on the TSFSn pin is not
an integer multiple of 125
s, this detection will be indicated by the
TCOFAI bit. If the TCOFAE bit is enabled, an interrupt will be reported by
the INT pin when the TCOFAI bit is ‘1’.
3.18.1.3
Transmit Multiplexed Mode
In the Transmit Multiplexed mode, since the demultiplexed data
rate on the system side (2.048 Mb/s) should be mapped to the data rate
in the line side (1.544 Mb/s), 3 kinds of schemes should be selected by
the MAP[1:0] bits. The schemes per G.802, per One Filler Every Four
CHs and per Continuous CHs are the same as the description in
In the Transmit Multiplexed mode, one multiplexed bus is used to
transmit the data to both two links. The data of Link 1 to Link 2 is byte-
interleaved input from the multiplexed bus. When the data on the multi-
plexed bus is input to two links, the sequence of the data is arranged by
setting the channel offset. The data to different links from one multi-
plexed bus must be shifted at a different channel offset to avoid data
mixing.
In the Transmit Multiplexed mode, the timing signal on the MTSCK
pin and the framing pulse on the MTSFS pin are provided by the system
side and common to allboth two links. The signaling bits on the MTSIG
pin are per-channel aligned with the corresponding data on the MTSD
pin.
In the Transmit Multiplexed mode, the data on the system interface
is clocked by the MTSCK. The active edge of the MTSCK used to sam-
ple the pulse on the MTSFS is determined by the FE bit. The active
edge of the MTSCK used to sample the data on the MTSD and MTSIG
is determined by the DE bit. The FE bit and the DE bit of the two links
should be set to the same value respectively. If the FE bit and the DE bit
are not equal, the pulse on the MTSFS is ahead. The MTSCK can be
selected by the CMS bit to be the same rate as the data rate on the sys-
tem side (8.192 MHz) or double the data rate (16.384 MHz). The CMS
bit of the two links should be set to the same value. If the speed of the
MTSCK is double the data rate, there will be two active edges in one bit
duration. In this case, the EDGE bit determines the active edge to sam-
ple the data on the MTSD and MTSIG pins. The pulse on the MTSFS pin
is always sampled on its first active edge.
In the Transmit Multiplexed mode, the MTSFS can indicate each F-
bit of the first link or the first F-bit of every SF/ESF/T1 DM/SLC-96 multi-
frame of the first link. The indications are selected by the FSTYP bit. The
active polarity of the MTSFS is selected by the FSINV bit. The FSTYP
bit and the FSINV bit of the two links should be set to the same value. If
the pulse on the MTSFS pin is not an integer multiple of 125
s, this
detection will be indicated by the TCOFAI bit. If the TCOFAE bit is
enabled, an interrupt will be reported by the INT pin when the TCOFAI
bit is ‘1’.
1.544
Mb/s
2.048
Mb/s
CH1
CH2
CH3
F
CH23
CH1
CH2
CH24
TS0
TS2
TS1
TS23
TS24
TS0
TS1
TS2
TS24
the 8th bit
CH24
TS3
TS25~TS31
the 8th bit
F
F CH1
discarded