Cabletron Systems SEH-34, SEH-32 Operating Specifications, General, Delay Times Start of Packets

INSTALLATION REQUIREMENTS/SPECIFICATIONS

2.4TRANSCEIVER REQUIREMENTS

When you connect an external network segment, via a transceiver, to the SEH with an EPIM-A, the following requirements must be met:

•The transceiver or Ethernet Device to which the module will be connected must meet IEEE 802.3 standards, and/or Ethernet Version 1.0 or Version 2.0 standards.

•The Signal Quality Error (SQE) test function on the transceiver must be disabled if you connect it to a repeater or to an Ethernet Version 1.0 device. In addition, some Version 2.0 equipment does not support the SQE test. Devices that do not support SQE test interpret the SQE test pulse as a collision.

2.5OPERATING SPECIFICATIONS

This section describes the operating specifications for the SEH. Cabletron Systems reserves the right to change these specifications at any time without notice.

GENERAL

Delay Times (Start of Packets):

Twisted Pair to EPIM- A	1.10 microseconds
Twisted Pair to Twisted Pair	1.00 microseconds
EPIM-A to Twisted Pair	1.00 microseconds
Delay Times (JAM):
Twisted Pair to EPIM-A	960 nanoseconds
Preamble:
Input:	Minimum of 40 bits required
Output:	64 bits min. (last 2 bits are 1, 1)

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