Appendix
D
D1
Error Counters
Error counters can provide you with a statistical summary of your
network’s activity. At each Data Highway II interface (except the
1779-KP5 Data Highway II/Data Highway Plus interface), a set of
counters is stored in memory to keep track of that node. You can access
these counters by using the following command format:
TNS
CMD
06
USER
NODE
LINK
FNC
01
SIZE
ADDR
STS
00
Enter the Link, Node,
and User components
of the destination
address.
Enter a 00 hex in
the Status byte.
Enter 01 hex in
the Function
Code byte.
Set this byte equal to
four times the number
of counters that you
will read. You can't
read more than 61
counters.
Set the Command
byte to 06 hex.
Increment the
Message
Transaction code.
Set this equal to
four times the first
counter number that
you want to read,
low byte first.
Each counter takes up four bytes. There are:
508 Counter Bytes (127 Counters) in the 1779-KP2 and 1779-KP3
320 Counter Bytes (80 Counters) in the 1779-KFL and 1779-KFM
Be sure that the sum of the values in the address (starting counter byte)
and size (the number of counter bytes to be read) fields does not exceed
the number of available counter bytes in the interface you are reading
from. If it does, you will receive an error.
Chapter Objectives