AB7319 Reading Modbus registers and not getting expected results

Anybus Support
#1

@anonjpzchdax
Hey Troy,

Can you send me a copy of that log? You can export it as a text file.

Thank you,

Kyle

  • They are reading 12 registers and everything seems correct except a watchdog bit that doesn’t appear to update
  • Rx is changing, but the bit in question is not:

‭D7 00 20 35 14 00 78 00‬ and ‭D7 00 20 35 0D 00 78 00‬

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
‭1101 0111 0000 0000 0010 0000 0011 0101 0001 0(1)00 0000 0000 0111 1000 0000 0000‬
D 7 0 0 2 0 3 5 1 4 0 0 7 8 0 0

‭1101 0111 0000 0000 0010 0000 0011 0101 0000 1(1)01 0000 0000 0111 1000 0000 0000‬
D 7 0 0 2 0 3 5 0 D 0 0 7 8 0 0

Documentation refers to Byte 1 Bit 1.

#3

@anonjpzchdax

The documentation says the watchdog is the second least significant bit (bit 1) of the second Byte (Byte 1).

image
image1165×401 40.5 KB

Which would lead me to believe it is this one:

image
image803×74 36.1 KB

Is it possible that the watchdog did not update?

Kyle

#5

That bit would change when the one from the customer would change. We could see this in the can side program change.

Mit freundlichen Grüßen / Best Regards

Troy Toomer

Field Service Engineer

#6

Hi Troy,

Have you spoken to the OEM and confirmed this information in the document, and asked for more information about how the RxWatchdog bit operates?

Kyle

#7

When it works they send a 1 we then send a 1 back, they then send a 0 and we respond with a 0 back and so on.

Mit freundlichen Grüßen / Best Regards

Troy Toomer

Field Service Engineer

#8

I do not have this device to test or troubleshoot with so in order for me to help, you will have to test it and send me detailed findings and logs.

What have you tried so far?

#10

Topic closed due to inactivity.