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FALC
56
PEF 2256 H/E
Functional Description T1/J1
User’s Manual
Hardware Description
160
DS1.1, 2003-10-23
5.4.2
Transmit Line Interface (T1/J1)
The analog transmitter transforms the unipolar bit stream to ternary (alternate bipolar)
return to zero signals of the appropriate programmable shape. The unipolar data is
provided on pin XDI and the digital transmitter.
Similar to the receive line interface three different data types are supported:
Figure 54
Transmitter Configuration (T1/J1)
Table 40
Parameter
Characteristic Impedance [
]
R
1
(
±
1%) [
]
t2 : t1
Ternary Signal
Single-rail data is converted into a ternary signal which is output on pins XL1 and
XL2. Selection between B8ZS or simple AMI coding with zero code suppression (B7
stuffing) is provided. B7 stuffing can be disabled on a per time slot basis (Clear
Channel capability). Selected by FMR0.XC1/0 and LIM1.DRS = 0.
Dual-rail data PCM(+), PCM(-) at multifunction ports XDOP and XDON with 50% or
100% duty cycle and with programmable polarity. Line coding is done in the same
way as in ternary interface mode. Selected by FMR0.XC1 = 1 and LIM1.DRS = 1.
Unipolar data on port XOID is transmitted in NRZ (non return to zero) with 100% duty
cycle or in CMI code with or without (SIC3.CMI) preprocessed by B8ZS coding to a
fiber-optical interface. Clocking off data is done with the rising edge of the transmit
clock XCLK (1544 kHz) and with a programmable polarity. Selection is done by
FMR0.XC1 = 0 and LIM1.DRS = 1.
Recommended Transmitter Configuration Values (T1/J1)
T1
100
2
1)
1 : 2.4
J1
110
1)
This value refers to an ideal transformer without any parasitics. Any transformer resistance or other parasitic
resistances have to be taken into account when calculating the final value of the output serial resistors.
F56V2_Transmtter_1
XL1
XL2
R
1
Line
t
2
t
1
R
1