The FRC control system includes a cRIO relay module for controlling pneumatic solenoids. The documentation refers to “the” module and specifies that it goes in slot 8 of the cRIO. It provides eight outputs, which is enough to control four dual solenoids. Our team’s early robot design looked like it was going to far exceed that number, requiring us to use Spikes for some solenoids.
I did some checking/hacking/experimenting and determined that the system supports a second relay module installed in the otherwise empty slot 7. I see only one rule that might potentially apply, and it doesn’t restrict using extra modules. Before I ask our TIMS contact to ask about this in the Q&A, does anyone else know of a reason it wouldn’t be legal?
After a very careful check of the documentation, I agree with your interpretation. If it were me, I would challenge any inspector to find out where this was prohibited; others with less gumption may want to verify this via Q&A.
Thank you, Mark. It’s good to see that the documentation does support the capabilities of the system.
That also confirms the small concern with <R45> that I hinted about – even with two cRIO relay modules installed, only one can control 24v solenoids.
Alan,
I would concur that it is legal and the only way to mix 12 and 24 volt solenoids without resorting to Spikes. i.e. one module powered by 24 volts and one by 12 volts.
After reading all the posts and reviewing the documentation, I agree with the conclusions you all have reached.
Although, I now have another question. If we are only going to use one solenoid module and it will be with 24 vdc solenoids, does it need to be in slot 7, or will either voltage work in either slot?
Bill -
Either voltage will work in either slot.
Alan -
You are only allowed one 24V bank of eight, because that is the power draw limitation of the 24V supply. 16 24V valves would likely trip the 24V breaker.
Thanks Eric,
That is what I assumed, but I didn’t want to get burned by another assumption, if you know what I mean.::ouch::
Our team is trying to use both slots, but LabView isn’t letting us program a solenoid as anything other than “slot 8”. Does anyone know how to fix that so we can use slot 7?
Thanks in advance…
One of the inputs to the Solenoid Open vi is the Solenoid Module number. Right-click it and choose Create Constant, and you’ll get an enumerated constant that acts as a popup menu, with Slot 7 and Slot 8 as options.
If what Alan told you doesn’t work, then I’d suspect the version of LabView you are running.
If it’s still not showing slot 8, tell us what Help -> About FIRST Robotics Competition Version says.
So we tried the right-click, create constant…and only slot8 shows up in the menu. We are running labview 8.6 frc 2010 competition software update .5
Any ideas? Are we missing an update or something?
You are indeed missing an update.
See: http://www.usfirst.org/roboticsprograms/frc/content.aspx?id=10934
Look under software, where it says Mandatory LabVIEW Update (if you have trouble with the link PM me-it was acting up when I just tried it).
We are currently at Update 2.0.
While you’re there also pickup the Driver Station update.
Keep watching that page, too. NI has said that there will be another Driver Station update released soon.
Ok, we thought we had, but in talking to our programmer is appears we only got the DS update. The page is timing out, though, so we have to see if it’s their site or our school’s firewall/blocking. Will it delete/overwrite our labview code or will our current projects/vi’s be untouched?
Thanks for the quick reply!!
It won’t clobber any existing projects, however, the default templates change and it would be worthwhile to copy or move your code over into the new template.