XRT72L50 Datasheet, PDF (321/471 Pages) Exar Corporation – SINGLE CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

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XRT72L50
SINGLE CHANNEL DS3/E3 FRAMER WITH HDLC CONTROLLER
REV. 1.2.1
FIGURE 128. ILLUSTRATION OF THE LOCAL RECEIVE E3 FRAMER BLOCK, RECEIVING AN E3 FRAME (FROM THE
REMOTE TERMINAL) WITH AN INCORRECT BIP-4 VALUE.
Local Terminal
Transmit E3
Framer
Receive E3
Framer
BIP-4 Nibble
Remote
Terminal
0xA
Locally Calculated
0xB
BIP-4 Nibble
FIGURE 129. ILLUSTRATION OF THE LOCAL RECEIVE E3 FRAMER BLOCK, TRANSMITTING AN E3 FRAME (TO THE
REMOTE TERMINAL) WITH THE A BIT-FIELD SET TO “1”
Local Terminal
Value = 1
Transmit E3
Framer
Receive E3
Framer
A Bit
Remote
Terminal
In additional to the FEBE bit-field signaling, the Receive E3 Framer block will generate the BIP-4 Error Interrupt
to the Microprocessor. Hence, it will set bit 2 (BIP-4 Error Interrupt Status) to “1”, as depicted below.
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