XR72L52 Datasheet, PDF (323/480 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
the Local Terminal Equipment Transmit E3 Framer block send the Remote Terminal an E3 frame, with the A
bit-field, set to “0”.
This procedure is illustrated in Figure 126 and Figure 127, below.
Figure 126 illustrates the Local Receive E3 Framer receiving an error-free E3 frame. In this figure, the locally
computed BIP-4 value of 0xA matches that received from the Remote Terminal, within the EM byte-field.
Figure 127 illustrates the subsequent action of the Local Transmit E3 Framer block, which will transmit an E3
frame, with the A bit-field set to “0”, to the Remote Terminal. This signaling indicates that the Local Receive E3
Framer has received an error-free E3 frame.
FIGURE 126. ILLUSTRATION OF THE LOCAL RECEIVE E3 FRAMER BLOCK, RECEIVING AN E3 FRAME (FROM THE
REMOTE TERMINAL) WITH A CORRECT BIP-4 VALUE.
Local Terminal
Transmit E3
Framer
Receive E3
Framer
0xA
Locally Calculated
BIP-4 Nibble
BIP-4 Nibble
Remote
Terminal
0xA
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