Using the Ethernet Port
870 USE 101 10 V..2 155
Description, Continued
Words 16, 17 High Word: Not used, always 0
Low Word: Peak Collision Detector
This field contains the number of consecutive collisions that occurred before the
frame was successfully transmitted out onto the Ethernet. Most transmitted frames
have zero collisions. Some have one collision on the first transmit attempt and
succeed on the second attempt. Some have more than one collision followed by
success. The largest number of consecutive collisions, since clear statistics
command, is stored and displayed in this field.
Receiver Errors
Words 18, 19
Framing Errors Counts the number of received frames addressed to this node that are greater than
320 bytes in length. Any such large frame has no relevance to the M1 Ethernet
adapter and therefore is skipped.
This error should not occur.
Overflow Errors Increments whenever a received frame cannot be copied into the frame buffer,
because the frame buffer is full. This situation should never occur under legal
Ethernet traffic.
Words 20, 21
CRC Errors Increments when the received packet is received under any of the following error
conditions:
lCRC error
lExtra data error
lRunt error
This counter can be made to increment by cont inuously disconnecting and
reconnecting the M1 Ethernet cable during cyclic communication.
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