Acromag 900EN-S005, Руководство пользователя

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BusWorks
®
900EN-S005 Ethernet Switch User’s Manual Ethernet I/O
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Acromag, Inc. Tel:248-624-1541 Fax:248-624-9234 Email:
sales@acromag.com http://www.acromag.com
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This feature allows each port to automatically select the best common mode
of operation with another node with respect to speed/duplex and will
automatically establish a half or full duplex connection at 10Mbps or
100Mbps as required.
Auto Negotiation Controls
CONTROL REGISTER FUNCTION
Port Control 12 bit 7 Set to disable Auto-Negotiation, clear to enable.
If AN is disabled, speed and duplex are
determined by bits 6 and 5 of Port Control 12
register.
Port Control 12 bit 6 If AN is disabled, set to force speed to
100baseT, clear to force 10baseT.
Port Control 12 bit 5 If AN is disabled or if AN is enabled but failed,
set to force Full-Duplex, clear to force Half-
Duplex.
Port Control 13 bit 5 Set to restart Auto-Negotiation. Clear for normal
operation.
Port Status 0 bit 6 Read Only to determine if port auto-negotiation
is done (set), or not done (clear).
Port Control 12 Bit 3 Advertise 100baseT Full-Duplex Capability
Port Control 12 Bit 3 Advertise 100baseT Half-Duplex Capability
Port Control 12 Bit 3 Advertise 10baseT Full-Duplex Capability
Port Control 12 Bit 3 Advertise 10baseT Half-Duplex Capability
Port Status 0 Bit 3 Read for 100baseT Full-Duplex Capable.
Port Status 0 Bit 2 Read for 100baseT Half-Duplex Capable.
Port Status 0 Bit 1 Read for 10baseT Full-Duplex Capable.
Port Status 0 Bit 0 Read for 10baseT Half-Duplex Capable.
This switch will automatically learn and store up to 1024 MAC addresses
with their port number and timestamp. It will update its look-up table with a
new entry if the packet’s source address does not already exist in the look-
up table, and if the received packet has no errors and is of legal length. If
the table is already full, the last entry of the table (oldest) will be deleted first
to make room for the new entry. The switch will also monitor whether a
station has moved and will update its table with new source port information
if a received packet’s source address is already in the table, and if the
received packet has no errors and is of legal length (auto-migration). The
switch will also update the time stamp information of a record whenever the
corresponding source address appears. It will use this timestamp to
determine the age of a record and if a record is not updated for 5 minutes,
the record will be removed from the table (auto-aging). Auto-aging may also
be optionally disabled via DIP switch 1 on the board.
TERMS AND
CONCEPTS
Auto-Negotiation/
Auto-Sense
Automatic Address
Management –
Learning, Aging,
Migration