2015 Power Distribution Board Trouble

[ZoNi7567]

Hi. So the for the past two days our team has finished wiring the basic electronics of the 2015 Control System, including the RoboRio and 4 talons so we can start programming our drivetrain. However, even though we've triple checked our wiring and found no error when compared to the wiring layout diagram that FIRST created, and we are able to connect to our robot on the Driver Station as well as upload code, the Power Distribution Board keeps on blinking red lights for both STAT and COMM. Furthermore, even though we have solid connection on the 2015 Driver Station and our battery is always fresh, enabling the robot does nothing (Even though there is code on the roboRio it doesn't run and the code is bug-free; We tested it already on our other practice bot that used the old cRio). As the programmer, I'm thinking that it might have to do with the flashing red lights STAT and COMM on the power distribution board because everything else on our robot seems to have no error at all. Would anyone happen to know how to fix the two blinking red lights on the PDB because I have found very few answers on what TWO blinking red lights means. Furthermore, is there any real difference in the API between the 2014 and 2015 Java language for the roboRIO because I couldn't find anything on that either?

[Ben Wolsieffer]

Red flashing lights probably mean there is something wrong with how the PDP is connected to the roboRiO over CAN. I would check the CAN wiring again and look on the roboRIO Webdashboard to see if the PDP appears as a connected device.

As to the differences between last year's and this year's code, they are documented here: http://wpilib.screenstepslive.com/s/...e-2014-to-2015

[ZoNi7567]

Hi Lopsided98. Our team didn't hook up a CAN. We directly connected 4 talons to 4 PWM ports on the roboRIO and hooked up power from the Blue Vbat controller on the PDB to the Input section of the roboRIO based on the 2015 Control System Wiring Layout released by First.

[ozrien]

Section 3 of the PDP User's Guide to shows that the red blink indicates "No CAN Comm."

Is the PDP's CAN port wired to the end of the CAN bus harness? If there are no other CAN devices then they go right to the roboRIO's CAN port. Also confirm if the the termination resistor jumper is set to the "ON" position.

enabling the robot does nothing (Even though there is code on the roboRio it doesn't run and the code is bug-free; We tested it already on our other practice bot that used the old cRio). As the programmer, I'm thinking that it might have to do with the flashing red lights STAT and COMM

So the symptom you are trying to fix is: why the robot doesn't move after you deploy your code? Are you using Talon SRs or SRXs? CAN or PWM? I'm guessing Talon SRs since you went back to the cRIO. Does the DS confirm you're teleop-enabled? If so are the Talon SR LEDs solid orange (neutral zero) or blinking orange (no signal)?

[ZoNi7567]

We aren't using the CAN on our robot. If you look at our attached photo, we wired our electrical in a simple way like the FRC Layout. I've attached the photos in a Google Drive Folder. https://drive.google.com/folderview?...&usp=sha ring

Also the DS does say that we are connected, the robot can be enabled, code IS on the robot, but no matter what I do nothing moves. I have my code in a txt file in the same Google Drive folder if anyone would like to take a look at it to see if there is any error with it

[ozrien]

So when your robot is enabled and the Talons are not driving, what are the Talon SR LEDs doing?

[ozrien]

If they are solid orange, then they are being commanded to neutral. Try debugging your logic.

If they are blinking orange, then they are not seeing a signal. Either because it's not physically in-circuit (bad pwm or connector is backwards) or the software isn't actually driving those channels.

[ozrien]

Also your Joystick constructor has a '1' instead of a '0'. I'm guessing in the Driver Station under the USB tab, the gamepad is in the '0' position. 0-indexing was introduced this year.

[Ben Wolsieffer]

You are required to use CAN to connect your PDP this year, even if you aren't going to use CAN for pneumatics or motor controllers (according to R61). Your robot won't work without it.

[Alan Anderson]

Summarizing what Omar and Ben have said:

Originally Posted by ZoNi7567

...we've triple checked our wiring and found no error when compared to the wiring layout diagram that FIRST created,...

Originally Posted by ZoNi7567

Hi Lopsided98. Our team didn't hook up a CAN.

Originally Posted by ZoNi7567

We aren't using the CAN on our robot. If you look at our attached photo, we wired our electrical in a simple way like the FRC Layout.

That wiring layout shows a dashed yellow line for CAN between the roboRIO and the PDP. <R61> requires that it be connected. The blinking lights on the PDP are telling you that it isn't.

[Arbalest007]

Hi Alan Anderson. I'm on the electrical team from the same team as Zoni here. So on the wiring layout, it shows that the CAN wire is connected from the roboRIO to the PDB with several Jaguars interlinked to the Pneumatics Module by a wire in between. To clarify, even if we use Talons then, we still need a wire from the roboRIO CAN Port to the Pneumatics Module then to the PDB CAN port is what you're saying? Thanks!

[ozrien]

Originally Posted by lopsided98

You are required to use CAN to connect your PDP this year, even if you aren't going to use CAN for pneumatics or motor controllers (according to R61). Your robot won't work without it.

I think it's worth pointing out that a robot that does not have the PDP CAN bus wired to the roboRIO can bus will still *basically function. The features that require the PDP to be connected are the current sensing and current logging. Certainly these features are not necessary to get your robot up and driving. So you really can't blame the rest of the robot not working on the observation that the PDP is not connected correctly.

However for your robot to be legal, then yep PDP has to be wired per R61. This guarantees at a minimum that you can walk up to any comp robot (with any language or even no program code) and monitor the current draws live (self test in roboRIO Web-page configuration) and also see previously logged currents (when the viewer becomes available).

Also everyone please note that the latest rule update requires 1.37 or newer PDP firmware, which is in your FRC install directory (C:\Users\Public\Documents\FRC).

EDIT...
*one wrinkle worth explaining, since the PDP has the 120Ω term resistor built-in, you may find it to be functionally necessary to add the PDP to CAN bus when using other CAN devices. However that resistor is always in circuit inside the PDP, and therefore does not depend on the firmware state or firmware version of the PDP.