XR72L52 Datasheet, PDF (447/480 Pages) Exar Corporation – TWO CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

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TWO CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
XRT72L52
REV. 1.0.1
FIGURE 192. ILLUSTRATION OF THE SIGNALS THAT ARE OUTPUT VIA THE RECEIVE OVERHEAD OUTPUT INTERFACE
(FOR METHOD 1).
RxOHClk
RxOHFrame
RxOH
FA1, Bit 7
FA1, Bit 6
FA1, Bit 5
FA1, Bit 4
FA1, Bit 3
Terminal Equipment should sample
the “RxOHFrame” and “RxOH” signals
here.
Recommended Sampling Edges
6.3.4.2 Method 2 - Using RxOutClk and the RxOHEnable signals
Method 1 requires that the Terminal Equipment be able to handle an additional clock signal, RxOHClk. Howev-
er, there may be a situation in which the Terminal Equipment circuitry does not have the means to deal with this
extra clock signal, in order to use the Receive Overhead Data Output Interface. Method 2 involves the use of
the following signals.
• RxOH
• RxOutClk
• RxOHEnable
• RxOHFrame
Each of these signals are listed and described in Table 86.
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