Stackable Personal Hubs
Installation and User Guide (04/01)
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4.0 OPERATION
This section details the various operational features of Magnum ST80 Personal
Hubs, including a description of the LED indicators. Stackable Personal Hubs are fully
compliant with the Ethernet Version 2/IEEE 802.3 Repeater Specification for CSMA/CD
10 Mbps operation and will function accordingly.
4.1 Functional
Operation,
Use of LED Indicators
Power On (PWR) LED
: Illuminates GREEN to show proper DC power.
Collision (COL) LED
: Illuminates YELLOW whenever a transmit collision
occurs on a port within the hub.
Link Status and Transmit (LINK/TX) LED:
Per port LEDs detect and
indicate by illuminating GREEN that there is proper connectivity on a 10BASE-
T network segment. The LED will turn off intermittently when the port
transmits a packet. In the event that connectivity is lost between the ends of that
segment or a loss of power occurs in the segment at either end, the LED is
turned off.
Note:
When port 8 is wired for up-link to another hub, the LINK LED
will normally be on when the up-link switch is set to the “X” position. With the
up-link switch off (“==”), LINK is off as the up-link is disabled. This permits
local operation of the ST80 Personal Hub with full bandwidth.
Polarity and Receive (POL/RX) LED:
Per port LEDs intermittently
illuminate GREEN to indicate that data packets are being received from the
segment. This provides a visual indication of network activity for re-assurance
of normal operation, and is also helpful in troubleshooting. If reversed polarity
is detected, the LED becomes steady GREEN (the ST80 automatically
compensates for the reversed polarity and resumes normal operation).
Partitioning and Re-connection:
Stackable Personal Hubs will automatically
partition any port where 32 consecutive collisions or 6.5 ms of continuous
transmissions occurs. Network integrity is checked every 800 ms and segment
re-connection occurs after one 512-bit packet is transmitted without error. The
status LEDs of a partitioned port indicate the partitioned state by blinking
alternately.
