DS32506/DS32508/DS32512
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Register Name:
LIU.TWSCR1
Register Description:
LIU Transmit Waveshaping Control Register 1
Register Address:
n * 80h + 24h
Bit #
15
14
13
12
11
10
9
8
Name
TWSC[15:8]
Default
0
Bit #
7
6
5
4
3
2
1
0
Name
TWSC[7:0]
Default
0
and STS-1 waveforms and the overshoot, one level, undershoot, and zero level segments for the E3 waveform.
Bits 15, 14: Transmit Waveshaping Control (TWSC[15:14]).
In DS3 and STS-1 modes, this field adjusts the
width of the first of two rising-edge segments. In E3 mode this field adjusts the width of the leading edge overshoot.
DS3/STS-1 Behavior
E3 Behavior
00 - normal first rise time
normal overshoot width
01 - increase first rise time by 0.1ns
increase overshoot width
10 - decrease first rise time by 0.1ns
decrease overshoot width
11 - decrease first rise time by 0.2ns
decrease overshoot width
Bits 13, 12: Transmit Waveshaping Control (TWSC[13:12]).
In DS3 and STS-1 modes, this field adjusts the
width of the second of two rising-edge segments. In E3 mode this field adjusts the width of the pulse plateau.
DS3/STS-1 Behavior
E3 Behavior
00 - normal second rise time
normal “one level” time
01 - increase second rise time by 0.1ns
increase “one level” time by 0.15ns
10 - decrease second rise time by 0.1ns
decrease “one level” time by 0.15ns
11 - decrease second rise time by 0.1ns
decrease “one level” time by 0.3ns
Bits 11, 10: Transmit Waveshaping Control (TWSC[11:10]).
In DS3 and STS-1 modes, this field adjusts the
width of the first of two falling-edge segments. In E3 mode this field adjusts the width of the trailing edge
undershoot.
DS3/STS-1 Behavior
E3 Behavior
00 - normal first fall time
normal undershoot width
01 - increase first fall time by 0.1ns
increase undershoot width by 0.15ns
10 - decrease first fall time by 0.1ns
decrease undershoot width by 0.15ns
11 - decrease first fall time by 0.1ns
decrease undershoot width by 0.3ns
Bits 9, 8: Transmit Waveshaping Control (TWSC[9:8]).
In DS3 and STS-1 modes, this field adjusts the width of
the second of two falling-edge segments. In E3 mode this field adjusts the width of the zero after the trailing edge.
DS3/STS-1 Behavior
E3 Behavior
00 - normal second fall time
normal “zero level” width
01 - increase second fall time by 0.1ns
increase “zero level” width by 0.15ns
10 - decrease second fall time by 0.1ns
decrease “zero level” width by 0.15ns
11 - decrease second fall time by 0.2ns
decrease “zero level” width by 0.3ns
Bits 7, 6: Transmit Waveshaping Control (TWSC[7:6]).
In DS3 and STS-1 modes, this field adjusts the
amplitude of the first of two rising-edge segments. In E3 mode this field adjusts the amplitude of the leading edge
overshoot. The 11 value is a special case in which the entire pulse is made narrower.
DS3/STS-1 Behavior
E3 Behavior
00 - normal first rise amplitude
normal overshoot
01 - decrease first rise amplitude 15%
decrease overshoot amplitude 2%
10 - increase first rise amplitude 15%
increase overshoot amplitude 2%
11 - decrease pulse width by 0.15ns
decrease pulse width by 0.15ns