Bt8370/8375/8376
3.11 Transmit LIU Registers
PULSE[2:0]
Fully Integrated T1/E1 Framer and Line Interface
Select Transmit Pulse Template—Each positive or negative pulse output on XTIP/XRING is
shaped to meet the transmit pulse template according to the selected cable length and type.
(Refer to Figure 2-34, TLIU Waveform and Figure 2-41, 0 dB LBO Isolated Pulse Template for
T1/E1 isolated pulse templates.) Each time the processor writes to TLIU_CR [addr 068], the
default shape values are transferred from internal ROM into SHAPE registers [addr 060–067].
Custom shape programming for alternative cable types or pulse templates will be discussed in
a separate Bt8370/8375/8376 application note.
PULSE
000
Cable Length
0–133 Ft
Cable Type
Application
T1 DSX
T1 DSX
T1 DSX
T1 DSX
T1 DSX
E1
100 Ω Twisted Pair
100 Ω Twisted Pair
100 Ω Twisted Pair
100 Ω Twisted Pair
100 Ω Twisted Pair
75 Ω Coaxial Cable
120 Ω Twisted Pair
100 Ω Twisted Pair
001
133–266 Ft
010
266–399 Ft
011
399–533 Ft
100
533–655 Ft
101
ITU–T G.703
ITU–T G.703
Long Haul FCC Part 68
110
E1
111
T1 CSU/NCTE
AISCLK
Enable Automatic ACKI Switching—When AISCLK is active and the clock monitor reports a
loss of transmit clock [TLOC; addr 048], the transmitter clock is automatically switched to
reference ACKI instead of TCKI, and the transmitter is forced to send AIS (all ones) data. If
both AISCLK and TAIS [addr 075] are active, AIS is transmitted using ACKI clock regardless
of the clock monitor status. Set AISCLK only if the system supplies an alternate line rate clock
on the ACKI pin.
Inputs
Status
RLOS/RLOC
Transmit
TAIS AUTO_AIS
AISCLK
TLOC
CLOCK
DATA
Normal
Normal
AIS
0
0
0
0
0
0
0
1
1
0
0
X
1
1
X
0
1
0
1
0
X
X
X
0
0
0
TCKI
TCKI
ACKI
TCKI
TCKI
ACKI
TCKI
ACKI
TCKI
0
1
1
0
Normal
Normal
AIS
1
0
1
1
X
1
1
1
X
X
X
AIS
X
X
X
X
AIS
AIS
3-66
Conexant
N8370DSE
CONEXANT [ CONEXANT SYSTEMS, INC ]
