Installation guide

Page 2-1
SPECIFICATIONS/REQUIREMENTS
CHAPTER 2
SPECIFICATIONS AND REQUIREMENTS
2.1 SPECIFICATIONS
Listed below are the electrical and physical specifications of the
MR9. Cabletron Systems reserves the right to change these
specifications at any time without notice.
General Specifications
Delay times (any segment in to all segments out)
Start of packet: 700 ns
Collision to JAM: 700 ns
Preamble
Input: 40 bits minimum to 64 bits maximum.
Output: 64 bits minimum (last 2 bits are 1,1).
JAM output: JAM pattern (1,0) is sent to all
segments when one segment detects a
collision.
Minimum packet
repeated: 96 bits including preamble. Packet
fragments are extended using the
JAM data pattern (1,0).
FAULT protection: Segment disconnect occurs after 32
consecutive collisions, or when a
segment’s collision detector is on for
longer than 2 to 3 ms. FAULT
protection resets after one packet is
transmitted onto the FAULTed
segment without causing a collision.