The second packet was a TEST packet (CTRL = F3) containing 3 bytes in the Protocol Data Unit. Since its DSAP (BC) was also not linked to a program, the packet was logged as an orphan.

This example illustrates two received packets logged to the event log file of the destination node (LU = 82).

Example 3. Bad Packet Entry in Event Log File

NM> RE,08–00–09–00–02–5A<RETURN>

 

 

 

 

 

 

TIME

DATE

ERR#

LU

DA

SA

LEN DSAP

SSAP CTRL

12:15 PM 15

OCT.

85 02

82

08000900025A

080009000230

05AA

A8

A4

03

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More...(’a’ to abort)

In Example 3, an Unnumbered Information packet (CTRL = 03) sent from Station Address 08"00"09"00"02"30 to Station Address 08"00"09"00"02"5A was logged. The packet was sent from a program whose SAP is A4 hex, to a program whose SAP is A8 hex (SSAP and DSAP are A4 and A8, respectively). This packet was logged with a packet length error (02 hex), presumably due to a mismatch between the length field (05AA bytes) and the actual packet length.

This example illustrates a received packet logged to the event log file of the destination node (LU = 82).

Example 4. Trace Packet Entry in Event Log File

NM> RE,08–00–09–00–02–30<RETURN>

 

 

 

 

 

 

TIME

DATE

ERR#

LU

DA

SA

LEN DSAP

SSAP CTRL

12:15 PM 15

OCT.

85 20

62

08000900025A

080009000230

00BA

0C

A4

03

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More...(’a’ to abort)

In Example 4, an entry shows that an Unnumbered Information packet (CTRL = 03) was transmitted from a program with SAP A4 on node 08"00"09"00"02"30, to a program with SAP 0C on node 08"00"09"00"02"30. The packet was logged because the transmit packet retry limit was exceeded due to collisions (ERR# = 20). (This example was generated by removing the 50"ohm terminators on the LAN cable.)

This example illustrates a transmit trace packet logged to the event log file of the source node (LU = 62).

Using Node Manager 5%51