Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 160)

Error Reporting
Chapter 7
7Ć5
30 A command rung syntax error has been detected in RUN mode after the prescan. This
means that either the communication zone has been altered by onĆline editing, hardware
problems, or a highway download operation, or that it has been moved by a gap or
ungap of a rung before the zone, or by changing the data table size.
31 This will not be generated by Revision F (1771ĆKA). Previous modules generated this
code if the start bit scanner detected a hard error on the PCĆtoĆmodule cable.
32 The data block of a read or write command is too large to fit in one Data Highway
message. This error causes the module to enter an error state.
33 An invalid command code was detected by the start bit scanner. This has the same
cause as Error 30. This error causes the module to enter an error state.
34 An invalid station address was detected by the start bit scanner. See Error 30. This
error causes the module to enter an error state.
35 The KA attempted to send an unprotected write or bit control command while the DIP
switch that enables unprotected commands was off. This can only occur at runĆtime if
the DIP switch that controls this option was changed without removing power from the
module.
36 The start bit was turned off after a message was sent but before the done bit, local error,
or remote error bit was set. This is the situation that causes the local error to turn on,
then off for 85 ms after the start bit is reset. The error code word is set before the local
error bit turns on.
37 The start bit was timed out by the automatic module timer before a reply message
arrived. This happens for one of the following reasons:
• Noise on the highway causes loss of a message. In this case the message
probably will succeed if it is retried.
• The remote station powered down or was disconnected from the highway while it
was processing the message. If the message is retried, it should get a 92 error.
• The timeout is too short. The minimum recommended timeout value is 2 seconds.
With a resolution of 1 second this allows the actual timeout to occur as soon as
1 second or as late as 2 seconds.
• A highway loading peak caused the timeout to be exceeded. If this is a rare
occurrence, it might be acceptable to just retry the message. Small increases (less
than 100%) in the timeout should eliminate this problem.
• Malfunction of a highway station is causing it to retain mastership for long periods
of time. Check for a station with a faulty receiver, or a bad highway cable. The
internal diagnostic counters will be most helpful in tracking this one.
50 Not used. Prior to Revision F (1771ĆKA) this may have occurred if a PC hard error
occurred while processing a reply message.
51 The reply message contains an invalid rung number. This should never occur unless
PCs are sending messages to a computer program that is not yet functioning properly.
This error will not cause the setting of an error bit or done bit.
52 A reply has been received at a PC that cannot send messages because it has no
command rungs. This should never occur unless faulty reply messages are sent by a
computer under debug. This error will not cause the setting of an error bit or done bit.