Dynomotion Forum

Hi everyone,
in a machine that we recently installed, we added a Konnect board to handle a set of additional I/O.
It is connected to Klfop+Kanalog set with a shielded cable (0.8m long). the last part of cable is separated and connected to IDC for abnout 30mm and then to Konnect connector.

It happens randomly that we receive the "COMM ERROR Signature not A5" after which Konnect is not operative any more and requires running the initialization sequence again to come alive.

I have two questions: can I detect in code the error and force the initialize again? (just to have a quick fix)
I found this:
viewtopic.php?f=6&t=1583&p=6043&hilit=Konnect#p6043
but it is not clear what the suggested function do; I suppose Idle mean "not connected" while "serviced" means connected and operative. Is it correct?

looking in the distance what can I do to avoid this error? we already have a shielded cable (shileld connected only on one side), but it is clearly not enough; is there any measure w can do to understand the problem.

Thank you

Giancarlo

Sorry i forgot to mention the exact error is:
"COMM ERROR Aux1 B7 (signature not A5)"

while konnect is initiaized with:

Hi Giancarlo,

Yes ServiceAux is a function pointer that points to a function to perform the next step in the communication sequence. If an error occurs communication is terminated and the pointer then points to an idle function.

What Version of software are you using. Some older Versions had some Konnect timing issues with certain configurations.

Receiving 0xB7 has 2 bits different than 0xA5. Bits 0 and 4. You might scope those bits for anything unusual.

0.8m is somewhat long. Is that required? What is the shield connected to? Probably best would be KFLOP GND on the KFLOP end only. Maybe post a photo of your wiring.

Are you using any of the power terminals or GND on Konnect?

Hi Tom,
thank you for the quick response.
the ac tual length is a bit less something like 65 cm... it is required by the routing. we could shorten it but not too much. I think we can go down to about 50cm but not less.

the cable shield is connected to a chassis where kflop and kanalog are contained, and it is on the main ground plane of the electrical cabinet.
the cabinet has a DB15HD on the wall directly connected to kflop on the inside.
The grounding route is a bit complicated because we use analog signals to command servo drives and the analog ground is connected to general ground. so 24V GND and any other ground on the main plate. this effectively vanicsh any possibility to isolate kflop from the rest of the grounds.
Anyway we use last version (5.4.1) and no power supply is drawn from konnect.

When you say we can scope for bits 0 and 4 you mean the first 8 bit from JP connector on kflop?

In themeantime I will insert in our watchdog routine a check for disconnection and try to reconnect on the fly.
Do we need to call also InitAux for this scope or we can just call AddKonnect (Assuming InitAux was already call once)?

Thank you

Giancarlo