FDDI uses 5-bit symbols (which are designed to prevent the sequence 0000) to transmit data, 2 symbols constitute a byte. Hence the bases and offsets are in Decimal. Unlike 802.5 Token Ring, I have assumed the Frame Status is part of the frame, and the bases and offsets assume that the end of the frame (-000) is at the end of the frame status field.

FDDI (X3.139-1987) Data Frame Format

offset
base
0 1 2 3 4 5 6 7 8 9
-040 Preamble
-030
-020
-010
+000 Start Delimiter
+010 Frame Control
+020 Destination Address
+030
+040
+050
+060
+070
+080 Source Address
+090
+100
+110
+120
+130

 

+140 Info
...
-070

 

-060 Frame Check Sequence
-050
-040
-030
-020 Ending Delimiter Frame Status
-010 Frame Status Continued

FDDI (X3.139-1987) Token Frame Format

offset
base
0 1 2 3 4 5 6 7 8 9
-040 Preamble
-030
-020
-010
+000 Start Delimiter
+010 Frame Control
+020 Ending Delimter

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