Advanced Troubleshooting - Leviton LumaCAN NPRPT-002 Guide D'installation

The repeaters works with a philosophy of store-and-forward. Each port
maintains a receive buffer and a transmit buffer for every other port. When
data comes in from the network, it is placed into a receive buffer corresponding
to the port that received the data. The repeater will then take the data from the
receive buffer and place it in the transmit buffer of all other ports. Each port
then will transmit data out of the transmit buffer. If a transmit buffer is full for any
port, data in the receive buffer will not be placed into any transmit buffer until
the buffer begins to empty. If the transmit buffer continues to be full causing the
receive buffer to eventually become full, any additional packets will be lost and
consequently packet loss will occur.
Ordinarily, buffer's will never become full. However, in cases of extreme loading
and poorly architected networks, problems may occur. To troubleshoot buffer
capacity problems, codes are transmitted to the USB port.
By connecting to the USB port and using a terminal program as described in
the section "Software Update", you can observe the following codes being
transmitted by the repeater indicating buffer full messages:
Transmit Buffer Full
Code Appearance: "ATBF"
• The first character, "A", is the port from which data was received
letter (A-F).
• The second character. "T" indicates a transmit buffer is full.
• The third character, "B", indicates the transmit buffer that is full (A-F).
• The fourth character, "F" indicates the buffer is full.
For example, a code of "ATBF" indicates that port A received a message that
is being held in the receive buffer because the transmit buffer for port B is full.
Receive Buffer near capacity
If a transmit buffer remains full for an extended period of time and the
receive buffer begins filling up, a code is transmitted once the receive
buffer is filled to 90% or above as follows:
Code Appearance: "FR+90"
• The first character, "F", is the receive port letter ( A-F).
• The second character, "R" indicates a receive buffer.
• The third character is a "+" sign indicating at or above.
• The fourth and fifth characters "90" indicate a percentage. At the
time of this writing, only 90 would ever be displayed.
For example, a code of "FR+90" indicates that port F's receive buffer is
90% (or greater) full.
Receive Buffer Full
Code Appearance: "BRF"
• The first character is the receive port letter (A-F).
• The second character, "R", indicates that it's a receive buffer.
• The third character, "F", indicates the buffer is full.
For example, a code of "BRF" indicates that port B's receive buffer is full.

ADVANCED TROUBLESHOOTING

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