Instruction Manual

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
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The X86 received frame is aborted if:
If 7d,7E is detected. This is an abort packet sequence in X.86.
Invalid FCS is detected.
The received frame has less than 6 octets.
Control, SAPI and address field are mismatched to the programmed value.
Octet 7d and octet other than 5d,5e,7e or dd is detected.
For the transmitter if X.86 is enabled the sequence of processing is as follows:
Construct frame including start flag, SAPI, Control and MAC frame.
Calculate FCS.
Perform transparency processing - 7E is translated to 7D5E, 7D is translated to 7D5D.
Append the end flag(7E).
Scramble the sequence X
43
+1.
Note that the serial transmit and receive registers apply to the X.86 implementations with specific exceptions. The
exceptions are outlined in the serial interface transmit and receive register sections.