Two Motors one PWM help?

[notmattlythgoe]

Originally Posted by RoboBucs

Ok, so the way it's set up, we have two motors hooked up to PWM 2, and the other two motors are hooked up to one each, PWM 0, and PWM 1. We can get the ones in PWM 0 and 1 to work, but it's the one in PWM 2 that we are having trouble with. It seems to be wired electrically fine I just can't get it work in labview. If it helps I can post some screenshots of what we have, just tell me if you need them.

This unfortunately is not legal, each motor controller must be hooked up to one port.

R57 Every relay module, servo, PWM motor controller shall be connected to a corresponding port on the roboRIO or via a legal MXP connection.

[Jefferson]

Originally Posted by notmattlythgoe

This unfortunately is not legal, each motor controller must be hooked up to one port.

Of course I'm not on the GDC, but I don't believe you are interpreting that correctly. The rule is there to prohibit teams from controlling servos, motor controllers, and relays with things other than the roboRIO. So a team can't have a Talon PWM cable plugged into an Arduino. It must go directly to the roboRIO.
I've never seen anything outlawing PWM splitters. In fact, they were included in the kit for years. Maybe as recently as 2013?

Now back to OP: are all of these motors drive motors? If so, why not have both sides on PWM splitters or both sides on two PWM outputs. Seems like things are necessarily complicated.

[Al Skierkiewicz]

Originally Posted by notmattlythgoe

This unfortunately is not legal, each motor controller must be hooked up to one port.

Matt,
R57 Every relay module, servo, and PWM motor controller shall be connected to a corresponding port (relays to Relay ports, servos and PWM controllers to PWM ports) on the roboRIO or via a legal MXP connection (per R58). They shall not be controlled by signals from any other source.

This actually provides that no other source can be used to provide control for the listed devices except the RoboRio. This is safety issue in that we know the RoboRio can be disabled/enabled via the FMS. Other devices likely would not provide this level of control and might cause robot movement when the robot is disabled. That is the underlying reason, active MXP boards must be pre-approved by FIRST Engineering.

To the OP, how are your two motors designed to operate? Are they connected together on a mechanism? Can you tell us what indications on the motor controllers are present?

[notmattlythgoe]

Originally Posted by Al Skierkiewicz

Matt,
R57 Every relay module, servo, and PWM motor controller shall be connected to a corresponding port (relays to Relay ports, servos and PWM controllers to PWM ports) on the roboRIO or via a legal MXP connection (per R58). They shall not be controlled by signals from any other source.

This actually provides that no other source can be used to provide control for the listed devices except the RoboRio. This is safety issue in that we know the RoboRio can be disabled/enabled via the FMS. Other devices likely would not provide this level of control and might cause robot movement when the robot is disabled. That is the underlying reason, active MXP boards must be pre-approved by FIRST Engineering.

To the OP, how are your two motors designed to operate? Are they connected together on a mechanism? Can you tell us what indications on the motor controllers are present?

Jefferson, thanks for the correction.

Al, thanks for the verification.

[RoboBucs]

Originally Posted by Al Skierkiewicz

Matt,
R57 Every relay module, servo, and PWM motor controller shall be connected to a corresponding port (relays to Relay ports, servos and PWM controllers to PWM ports) on the roboRIO or via a legal MXP connection (per R58). They shall not be controlled by signals from any other source.

This actually provides that no other source can be used to provide control for the listed devices except the RoboRio. This is safety issue in that we know the RoboRio can be disabled/enabled via the FMS. Other devices likely would not provide this level of control and might cause robot movement when the robot is disabled. That is the underlying reason, active MXP boards must be pre-approved by FIRST Engineering.

To the OP, how are your two motors designed to operate? Are they connected together on a mechanism? Can you tell us what indications on the motor controllers are present?

We used a wire splitter to connect two of the four talon drive motors we have to a single PWM. Again I believe the wiring is fine, here some pocture of what we have in labview.
[IMG][/IMG]
[IMG][/IMG]
[IMG][/IMG]

[Mark McLeod]

A few things are wrong here.

If all four of these motors are for driving, then you need some consistency.
Either:

1. Change Open 2 Motor to Open 4 Motor in Begin and use 4 PWM outputs
2. Or keep Open 2 Motor and use PWM Y splitters on both sides of your drive train

The immediate things wrong with what you are doing:
PWM 0 and PWM 1 are signals for opposite sides of the drive train. So those are where your two splitters should come from. One splitter for each side.
The Arcade Drive is mixing the joystick x/y to produce the correct PWM0 & 1 outputs. The Dual Motors isn't compatible that that.

Motor Set Output has an incorrect wire.
The one with the red dot needs to be removed.
It looks like you are trying to treat it like Arcade Drive. It isn't.

There are duplicates for Robot Drive Motors, Joystick 1/Axes/Buttons, etc. setting every one of these in two places. Only one will win.

[RoboBucs]

Originally Posted by Mark McLeod

A few things are wrong here.

If all four of these motors are for driving, then you need some consistency.
Either:

1. Change Open 2 Motor to Open 4 Motor in Begin and use 4 PWM outputs
2. Or keep Open 2 Motor and use PWM Y splitters on both sides of your drive train

The immediate things wrong with what you are doing:
PWM 0 and PWM 1 are signals for opposite sides of the drive train. So those are where your two splitters should come from. One splitter for each side.
The Arcade Drive is mixing the joystick x/y to produce the correct PWM0 & 1 outputs. The Dual Motors isn't compatible that that.

Motor Set Output has an incorrect wire.
The one with the red dot needs to be removed.
It looks like you are trying to treat it like Arcade Drive. It isn't.

There are duplicates for Robot Drive Motors, Joystick 1/Axes/Buttons, etc. setting every one of these in two places. Only one will win.

YES it worked!!! Thank you so much!