XRT72L50 Datasheet, PDF (424/471 Pages) Exar Corporation – SINGLE CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

XRT72L50
SINGLE CHANNEL DS3/E3 FRAMER WITH HDLC CONTROLLER
REV. 1.2.1
áç
FIGURE 184. ILLUSTRATION OF THE LOCAL RECEIVE E3 FRAMER BLOCK, RECEIVING AN E3 FRAME (FROM THE
REMOTE TERMINAL) WITH A CORRECT EM BYTE.
Local Terminal
Transmit E3
Framer
Receive E3
Framer
EM Byte
0x5A
0x5A
Locally Calculated
EM Byte
Remote
Terminal
FIGURE 185. ILLUSTRATION OF THE LOCAL RECEIVE E3 FRAMER BLOCK, TRANSMITTING AN E3 FRAME (TO THE
REMOTE TERMINAL) WITH THE FEBE BIT (WITHIN THE MA BYTE-FIELD) SET TO “0”
Local Terminal
FEBE bit
x0xxxxxx
Transmit E3
Framer
Receive E3
Framer
MA Byte
Remote
Terminal
However, if the locally computed BIP-8 value does not match the EM byte of the corresponding E3 frame, then
the Receive E3 Framer block will do the following.
411