PEB22554 SIEMENS [Siemens Semiconductor Group], PEB22554 Datasheet - Page 123

• Manufacturer Part Number: PEB22554
• Description: ICs for Communications
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Semiconductor Group
Transmit Pulse-Mask 0...2 (Read/Write)
Value after RESET: 7B
XPM0
XPM1
XPM2
The transmit pulse shape which is defined in ITU-T G.703 will be output on pins XL1 and
XL2. The level of the pulse shape can be programmed via registers XPM2-0 to create a
custom waveform. In order to get an optimized pulse shape for the external transformers
each pulse shape will be internally devided into four sub pulse shapes. In each sub pulse
shape a programmed 5 bit value will define the level of the analog voltage on pins XL1/2.
Together four 5 bit values have to be programmed to form one complete transmit pulse
shape. The four 5 bit values will be sent in the following sequence:
Changing the LSB of each subpulse in registers XPM2-0 will change the amplitude of the
differential voltage on XL1/2 by approximately 80 mV.
Example: 120
Programming values for XPM0-2: 7B
XLT…
DAXLT...
7
XP12
XP30
XLLP
interface and wired as shown in figure 22.
XP04-00: First pulse shape level
XP14-10: Second pulse shape level
XP24-20: Third pulse shape level
XP34-30: Fourth pulse shape level
XPM04-00: 1B
XPM14-10: 1B
XPM24-20: 00
XPM34-30: 00
Transmit Line Tri-state
0…
1…
Disable Automatic Tristating of XL1/2
0...
XP11
XP24
XLT
H
, 03
Normal operation
Transmit line XL1/XL2 or XDOP/XDON are switched into high
Normal operation. If a short is detected on pins XL1/2 the
impedance state. If this bit is set the transmit line monitor status
information will be frozen.
transmit line monitor will set the XL1/2 outputs into a high
impedance state.
DAXLT
H
XP10
XP23
, 00
H
H
H
H
H
or 27 decimal
or 27 decimal
H
XP04
XP22
, 03
123
H
, 00
XP03
XP21
XP34
H
XP02
XP20
XP33
Operational Description E1
XP01
XP14
XP32
0
XP00
XP13
XP31
PEB 22554
(x26)
(x27)
(x28)
09.98