EMM-E6 Ethernet User's Guide

APPENDIX A: EMM-E6 SPECIFICATIONS
A-2 EMM-E6 User’s Guide
A.2 REPEATER FUNCTIONALITY
Delay Times
(port x in to port x out)
Start of Packet: 1,450 ns max.
Collision to JAM: 1,550 ns max.
Preamble
Input: Minimum of 40 bits to a max. of 64 bits
required.
Output: 64
bits min. (last 2 bits = 1, 1).
JAM Output: If a collision occurs on one of the segments, a
pattern of 1,0 is sent to the other segments.
Minimum Packet Repeated: 96 bits including preamble. (Packet
fragments are extended using the JAM [1,0]
data pattern.)
FAULT Protection: Each segment will disconnect itself from the
other segments if 32 consecutive collisions
occur, or the collision detector of a segment is
on for longer than approximately 2.4 ms. This
FAULT protection will reset automatically
after one packet is transmitted onto the
FAULT protected segment without causing a
collision.
CH1Book Page 2 Wednesday, March 20, 1996 7:48 AM