XRT72L56 Datasheet, PDF (338/486 Pages) Exar Corporation – SIX CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

XRT72L56
SIX CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
REV. P1.1.2
áç
PRELIMINARY
FIGURE 140. 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 141. 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 Re-
ceive E3 Framer block will generate the BIP-4 Error
Interrupt to the Microprocessor. Hence, it will set bit 2
(BIP-8 Error Interrupt Status) to “1”, as depicted be-
low.
319