AM79C983AKCW AMD [Advanced Micro Devices], AM79C983AKCW Datasheet - Page 43

• Manufacturer Part Number: AM79C983AKCW
• Manufacturer: AMD [Advanced Micro Devices]

Short Events
Address:
Short Events is a read-only attribute that counts the
number of instances where activity is detected with a
duration less than the ShortEventMaxTime (74-82 bit
times). This attribute is a 32-bit counter with a minimum
rollover time of 16 hours.
Runts
Address:
Runts is a read-only attribute that counts the number of
instances where activity is detected with a duration
greater than the ShortEventMaxTime (74-82 bit times,
but less than the minimum valid frame time (512-bit
times, or 64 bytes). This attribute is a 32-bit counter
with a minimum rollover time of 16 hours.
Note: Runts usually indicate collision fragments, a
normal network event. In certain situations associated
with large diameter networks, a percentage of runts
may exceed ValidPacketMinTime.
Collisions
Address:
Collisions is a read-only attribute that counts the num-
ber of instances where a carrier is detected on the port,
and a collision is detected. This attribute is a 32-bit
counter with a minimum rollover time of 16 hours.
Byte 0
Byte 1
Byte 2
Byte 3
Byte 0
Byte 1
Byte 2
Byte 3
Byte 0
Byte 1
Byte 2
Byte 3
bit 7
bit 31
bit 31
bit 31
D Port Read
MSB
D Port Read
bit 7
MSB
D Port Read
bit 7
MSB
1110 0101
1110 0110
1110 0111
P R E L I M I N A R Y
bit 0
bit 24
bit 0
bit 24
bit 0
bit 24
LSB
LSB
LSB
Am79C983A
Late Events
Address:
Late Events is a read-only attribute that counts the
number of instances where a collision is detected after
the LateEventThreshold (480-565 bit times) in the
frame. This event will be counted both by the Late
Events attribute, as well as the Collisions attribute. This
attribute is a a 32-bit counter with a minimum rollover
time of 81 hours.
Very Long Events
Address:
Very Long Events is a read-only attribute that counts
the number of times the transmitter is active in ex-
cess of the MAU Jabber Lockup Protection (MJLP)
Timer (4 ms - 7.5 ms). This attribute is a 32-bit
counter with a minimum rollover time of 198 days.
Data Rate Mismatches
Address:
Data Rate Mismatches is a read-only attribute that
counts the number of occurrences where the frequency
or data rate of the incoming signal is detectably differ-
ent from the local transmit frequency. To be counted,
the incoming packet must be at least 512 bytes and not
in collision. The attribute is a 32-bit counter with a min-
imum rollover time of 80 hours.
Note: The rate at which the Data Rate Mismatches
attribute will increment will depend on the magnitude of
the difference between the received signal clock and
the local transmit frequency.
Byte 0
Byte 1
Byte 2
Byte 3
Byte 0
Byte 1
Byte 2
Byte 3
Byte 0
Byte 1
Byte 2
Byte 3
D Port Read
bit 7
bit 31
D Port Read
bit 7
bit
MSB
D Port Read
bit 7
bit 31
MSB
MSB
31
1110 1000
1110 1001
1110 1010
bit 0
bit 24
bit 0
bit
bit 0
bit 24
LSB
LSB
LSB
24
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