pef22504 Infineon Technologies Corporation, pef22504 Datasheet - Page 88

• Manufacturer Part Number: pef22504
• Description: Quad E1/t1/j1 Line Interface Component For Long- And Short-haul Applications Pef 22504 E, Pef 22504 Ht, Version 2.1
• Manufacturer: Infineon Technologies Corporation

is necessary. So switching between both channels on line side is possible using only one signal as it is shown in
Figure
If XLT or XLT is configured, the value of the register bit XPM2.XLT and the value of XLT are logically ored to control
the transmit line side. (That means if XPA is configured as low active then the line side is in tristate mode for
tristate = XPM2.XLT or not(XPA).
Because the register bit XPM2.XLT and the Multi Function Port XPA exist individually for every channel, switching
on the line side in transmit direction can be done between channels of different or of the same QuadLIU
This enables a simple application using only one common board signal for switching between two channels were
both transmit channels are working in parallel (see
is switched into transmit line tristate mode.
The receive system interface pins RDO, RSIG, SCLKR and RFM can be set by software into tristate mode
constantly using the register bit SIC3.RRTRI. In this mode “tristate” means high impedance against V
No internal pull up or pull down resistor is present.
Combined hardware and software controlling of the tristate mode can be done by a hardware signal if a Multi
Function Port is configured as RTDMT input . It is proposed that the Multi Function Port RPA be used for RTDMT,
if this is the case then the PC1.RPC1(3:0) register bits must be programed, see
the value of the register bit SIC3.RRTRI and the value of RTDMT are logically exored.
This enables a simple application using only one common board signal for switching between two channels. While
one of them is driving the system receive interface, the other one is switched into tristate mode.
An overview about the tristate configurations of RDO, RSIG, SCLKR and RFM is given in
Table 17
SIC3.RRTRI /
SIC3.RRTRI exor RTDMT
if RTDMT is selected on
Multi Function Port
1
0
0
Switching between both channels can be done on the system side in the receive direction by using the register bit
SIC3.RRTRI and with or without selection of the Multi Function Port as RTDMT. If the RTDMT function is selected,
the values of RTDMT and SIC3.RRTRI are logically exored. If in one channel SIC3.RRTRI is set, RTDMT is active
low because of the logical exor, and if in the other channel SIC3.RRTRI is cleared, RTDMT is active low because
of the logical exor. So switching between both channels on the system side in the receive direction is possible
using only one board signal.
For application using RLM for protection switching the XLT, XLT and RTDMT Multi Function Ports operate in
conjunction with the SIC3.RRTRI bits. Switching between channels can be done together on the system and the
line side with only one common board signal, connected to XPA (XLT, XLT) and RPA (RTDMT), as shown in
Figure 27
level channel 1 is in stand-by and channel 2 is active.
Different line impedances require different resistor values as shown in
that LIM0.RTRS and GPC1.MPAS must be always ´0´.
If both channels are configured identically and supplied with the same system data and clocks, the transmit path
can be switched from one channel to the other without causing a synchronization loss at the remote end.
Data Sheet
27.
and
Tristate Configurations for the RDO, RSIG, SCLKR and RFM Pins
Table
17: If this signal has low level channel 1 is active and channel 2 is in stand-by, if it has high
X
0
1
SIC3.RTRI
Figure
88
Constant tristate (without
pull up and pull down
resistor)
Never tristate
Tristate during inactive
channel phases (with pull
up resistor
27). While one of them is driving the line, the other one
Pins RDO and RSIG
Table
16. Both switches are always off so
Table
Pins SCLKR and RFM
Constant tristate (without
pull up and pull down
resistor)
Never tristate
Never tristate
34. If RTDMT is configured
Functional Description
Table
Rev. 1.3, 2006-01-25
17.
QuadLIU
PEF 22504
DD
TM
and V
device.
TM
SS
: