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FALC
56
PEF 2256 H/E
Operational Description E1
User’s Manual
Hardware Description
197
DS1.1, 2003-10-23
E1 Initialization
For a correct start up of the primary access interface a set of parameters specific to the
system and hardware environment must be programmed after reset goes inactive. Both
the basic and the operational parameters must be programmed
before
the activation
procedure of the PCM line starts. Such procedures are specified in ITU-T and ETSI
recommendations (e.g. fault conditions and consequent actions). Setting optional
parameters primarily makes sense when basic operation via the PCM line is guaranteed.
Table 48
gives an overview of the most important parameters in terms of signals and
control bits which are to be programmed in one of the above steps. The sequence is
recommended but not mandatory. Accordingly, parameters for the basic and operational
set up, for example, can be programmed simultaneously. The bit FMR1.PMOD should
always be kept low (otherwise T1/J1 mode is selected).
PC(4:1)
00
H,
00
H
00
H,
00
H
00
H
00
H
Input function of ports RP(A to D): SYPR,
Input function of ports XP(A to D): SYPX
SCLKR, SCLKX, RCLK configured to inputs,
XMFS active low, CLK1 and CLK2 pin configuration
The activity level of port XMFS can be selected to be active
high or active low by programming PC5.CXMFS. This bit
must not be set, if XMFS is not enabled as an input. XMFS
input selection is done by programming one of the
Transmit Multifunction Ports, using registers
PC4(4:1).XPC(3:0).
Note: XMFS must not be used together with SYPX on
different Multifunction Ports.
PC5
PC6
Table 48
Initialization Parameters (E1)
Configuration
Basic Set Up
Master clocking mode
Register Setting
GCM(8:1) according to external MCLK
clock frequency
FMR1.PMOD = 0
LIM0, LIM1, XPM(2:0)
E1 mode select
Specification of line interface and clock
generation
Line interface coding
Loss-of-signal detection/recovery
conditions
FMR0.XC(1:0), FMR0.RC(1:0)
PCD, PCR, LIM1, LIM2
Table 47
Register
Initial Values after Reset (E1)
(cont’d)
Reset Value
Meaning