
TMXF28155 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Preliminary Data Sheet, Rev. 1
October 2000
402
Lucent Technologies Inc.
28-Channel Framer Block Functional Description
(continued)
DS1 Transparent Framing Format
The transmit framer can be programmed to transparently transmit 193 bits of CHI system data to the line.
When configured for transparent framing, the transmit framer extracts from the receive CHI system data bit 8 of
time slot 1 and inserts this bit into the framing bit position of the transmit line data. The other seven bits of the
receive system time slot 1 are ignored by the transmit framer. The receive framer will extract the framing bit (or
193rd bit) of the receive line data and insert it into bit 8 of time slot 1 of the CHI system data. The other bits of time
slot 1 are set to 0.
Frame integrity is maintained in both the transmit and receive framer sections.
5-5989(F).ar.1
Figure 50. DS1 Transparent Frame Structure
In transparent framing mode 1, the receive framer is forced not to reframe on the receive line data. Other than bipo-
lar violations and unframed AIS monitoring there is no processing of the receive line data. The receive framer will
insert the 193rd bit of the receive line data into bit 8 of time slot 1 of the transmit system data.
Bit 8 of time slot 1 of the receive system interface is inserted as the 193rd data bit into the transmit line data.
Transparent framing mode 1 is selected by setting FRM_LNK_TRANSP (Table 456) to 1 and FRM_MODE[3:0]
(Table 457) to 1000 (non-align 193rd bit).
In transparent framing mode 2, the receive framer functions normally on receive line data. All normal monitoring of
receive line data is performed and data is passed to the transmit CHI as programmed. The receive framer will
insert the extracted framing bit of the receive line data into bit 8 of time slot 1 of the transmit system data. The
remaining bits in time slot 1 are set to 0.
Bit 8 of time slot 1 of the receive system interface is inserted in the transmit line framing bit position.
Transparent framing mode 2 is selected by setting FRM_LNK_TRANSP (Table 456) to 1 and selecting the appro-
priate framing mode with FRM_MODE[3:0] (Table 457).
TIME SLOT 1
(STUFF TIME SLOT)
32 TIME-SLOT CHI FRAME
TIME SLOT 2
TIME SLOT 3
TIME SLOT 31 TIME SLOT 32
0
0
0
0
0
0
0
F BIT
TRAMSMIT FRAMER’S
193-bit FRAME
DS1 = 125
μ
s
TIME SLOT 1
TIME SLOT 2
TIME SLOT 24
F BIT