Maxim DS33R11 specifications 19 X.86 Encoding and Decoding, Laps Encoding of MAC Frames Concept

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver

9.19 X.86 Encoding and Decoding

X.86 protocol provides a method for encapsulating Ethernet Frame onto LAPS. LAPS provides HDLC type framing structure for encapsulation of Ethernet frames. LAPS encapsulated frames can be used to send data onto a SONET/SDH network. The DS33R11 expects a byte synchronization signal to provide the byte boundary for the X.86 receiver. This is provided by the RBSYNC pin. The functional timing is shown in Figure 12-4. The X.86 transmitter provides a byte boundary indicator with the signal TBSYNC. The functional timing is shown in Figure 12-3. Note that in some cases, additional logic may be required to meet RSYNC/TSYNC sychronization timing requirements when operating in X.86 mode.

Figure 9-12. LAPS Encoding of MAC Frames Concept

IEEE

802.3MAC Frame

LAPS

Rate Adaption

SDH

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