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FALC
56
PEF 2256 H/E
T1/J1 Registers
User’s Manual
Hardware Description
381
DS1.1, 2003-10-23
XDOS
Transmit Data Out Sense
0 =
Output signals XDOP/XDON are active low. Output XOID is
active high (normal operation).
1 =
Output signals XDOP/XDON are active high. Output XOID is
active low.
Note: If CMI coding is selected (FMR0.XC(1:0) = 01) this bit has to
be cleared.
The transmit frame marker XFM is independent of this bit.
DCIM
Digital Clocking Interface Mode
0 =
Default T1/J1 data operation.
1 =
Selects Synchronization interface mode. A 1.544-MHz receive
clock signal must be applied on RL1/RL2. The transmit clock
signal must be derived from the clock connected to SCLKX
(CMR1.DXSS = 1). The recommended XPM programming
values are:
XPM0 = EF
H
, XPM1 = BD
H
, XPM2 = 07
H
RLM
Receive Line Monitoring
0 =
Normal receiver mode
1 =
Receiver mode for receive line monitoring;
the receiver sensitivity is increased to detect resistively
attenuated signals of -20 dB (short-haul mode only)
LL
Local Loop
0
=
Normal operation
1
=
Local loop active. The local loop-back mode disconnects the
receive lines RL1/RL2 or RDIP/RDIN from the receiver. Instead
of the signals coming from the line the data provided by system
interface is routed through the analog receiver back to the
system interface. The unipolar bit stream is transmitted
undisturbedly on the line. Receiver and transmitter coding must
be identical. Operates in analog and digital line interface mode.
In analog line interface mode data is transferred through the
complete analog receiver.
MAS
Master Mode
0
=
Slave mode
1
=
Master mode on. Setting this bit the DCO-R circuitry is
frequency synchronized to the clock (1.544, 2.048 MHz or
8
kHz, see IPC.SSYF, LIM1.DCOC) supplied by SYNC. If this
pin is connected to V
SS
or V
DD
(or left open and pulled up to V
DD