Differences between 2009 and 2010 Digital Sidecar???

[PhilBot]

I have question about changes from the 2009 Digital Sidecar to the 2010 Digital Sidecar. I posted on NI.com, but figured this forum is also a hotbed of NI developers

The reason for my enquiry was an extremely odd situation that occurred during robot testing last night.

We were driving our robot around (over bumps) and after a hard impact; it disabled itself (or so it seemed). Long story short, we found that some metal shavings had gotten down into the 2010 DS that was installed, and was causing intermittent +5V Power problems.

So we replaced the 2010 DS with a 2009 DS that we had as a spare from last year.

The robot proceeded to run normally, except for one thing…. When the robot was disabled, it still proceeded to run the compressor. And it wasn’t just running mindlessly, it was responding correctly to the Pressure switch.

I didn't think this was possible!!!

So... even though the robot was disabled (we even unplugged the Wireless Gateway), and the Victors were disabled, the Compressor relay was fully operational.

We tested several components to see if we had caused some other item to fail because of the impact, but the CRIO, Relay Module, and Solenoid Breakout all checked out. We even re-loaded several old software versions, but the compressor still ran when disabled (starting and stopping as air was needed).

Caused about 30 min of serious head-scratching....

In the mean time, we had cleaned out the 2010 DS, and decided to place it back in the robot. When we did, the compressor went back to behaving correctly (stopping when the robot was disabled).

The only thing that I can think of to cause this would be that the method used to disable the DS outputs had changed from 2009 to 2010.

Can anyone shed any light on how a 2009 Sidecar could generate outputs when the robot is disabled... I was under the impression that the underlying FPGA code inhibited any outputs when there was no coms or the robot was disabled.

Phil.

[EricVanWyk]

Phil -

It isn't a difference between 2009 and 2010, it is that your 2009DSC has a very specific failure. The inhibit signal is likely shorted to "enabled".

You may be able to repair it by removing swarf. I'll check back with you in a bit, via PM.

[jhersh]

Because the RSL and the relay outputs are on the same SPI chain, we continue shifting out all of that data and rely on the output enable signal of the shift register to disable the relays. As Eric suggested, your output enable signal seems to be damaged or shorted in that sidecar.

In retrospect, I should have been more paranoid and not only used the output enable signal but also zeroed out the relay data. Oh well... something to fix next year I guess.

-Joe

[PhilBot]

Thnaks for the feedback guys... At least I wasn't going crazy.......



or was I ?

[EricVanWyk]

Phil, you've been involved with the beta efforts TWICE*. You are quite definitely crazy.





*THANK YOU THANK YOU THANK YOU

[apalrd]

Originally Posted by PhilBot

\So we replaced the 2010 DS with a 2009 DS that we had as a spare from last year....

The quick and easy way to clean out shavings is to turn your robot upside-down and "bang the drums" on the bottom of it. This assumes your DSC is mounted facing up. We have had metal shorts on DSC channels at least two times this year, its really annoying, but this always fixes the problem rather quickly.