MSP Launchpad

Hello everyone, I’m having some trouble with the MSP launchpad, I’m connecting the digital output pins to the 3.3V pin, but every trime I do this on the left side of the device, it crashes. Any advice?

Also, it appears that many of the pins on the left side are in continuity with +3.3v already

Which option have you configured it for? The items in light blue are buttons, you short them to ground and they complete the circuit and the button is ‘pushed’ on the dashboard. The pink ones are joystick axis’s, you connect them to a joystick or POT and they act as an axis. The green ones are indicators, we used them to light up LEDs on the 2ndary drivers station. We had them change colors depends on if your in auton or teleop.

Also, whilst plugged into a usb port, it appears every pin on the left side is in continuity, but it still only crashes into what I presume is a safety to stop direct shorts when I connect some switches.

I have it programmed to option 3

The article linked says to short the digital input with VCC (3.3v) which I do and the Launchpad resets, I just tried ground and nothing happens when shorted to ground with the input

Sorry yes this should show as button pressed.

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Normally I’d be connecting Digital output pins (signal) on one side of a light with Ground on the other.
Buttons would be Digital inputs connected in the same fashion-signal to ground.

What are you connecting that needs power, other than the power that the signal will provide?

Nothing that needs power, just a switch, not even with a light. I’m using the digital input pins, not the output

A switch goes from Digital Input on one side to Ground on the other.
(Correction: Not on the MXP board. It seems to be a low-side switch, so 3.3v to button grounds it.)

As I’ve stated, I’ve also tried that and it did nothing. The documentation states to use one of the Digital input pins and short it to +3.3v. That resets the LP. Shorting to ground does absolute nada. As well, shorting +3.3v to Din pins on the right side does show a button as pressed in the driverstation

I’ll go plug one in and test it.

Yea I am not near ours, I we have a spare which was never programmed. I can check it tonight and see. Maybe you got a bum unit.

It worked last year just fine, I don’t think we’ve done anythng that should’ve broken it. We can order a new one if need be

It appears that the entire right side works just fine, I’ve connected 3.3v from the left side(seemingly one of the only good pins) to the Dins from the right side and I’ve gotten all 10 of my current buttons to display in the driver-station, so at least it works and isn’t critical to fixing the left side, however if this isn’t intended behavior I’m unsure of how reliable the unit as a whole would be

Can confirm that mine works on the left side connecting Button 1 to 3.3v
It shows up as button 1 on the Driver Station USB tab.

Nothing stuck in a hidden spot, like the connector on the back, to short things?

The connector is how I’m using it, I have a 2x10idc breakout board, I’m using it on both sides and as I’ve said the right side works fine, I’ve checked the connection on the left and nothing is inside, and the pins on top are clean. I’ve also tried without the IDC board connected whatsoever and just some wire with female connectors on each side, and it still doesn’t work

I’d have to vote board damage.
I tested mine with just a jumper wire between 3.3v and each of the button inputs up to Button 16 (buttons beyond 16 aren’t recognized by the Driver Station).

Do you have your software/ code to post for what you are trying to do? Also what you are meaning by resetting. It should only resets when it is power cycled or the reset pin is toggled. The G5529 launch pad has two switches/buttons on the board. They are wired to P2.1 and P1.1 to be able to test buttons without having to do any wiring. In my experience not all bread boards are created equal. If everything on the left side of the breakout board is not working I would start that trouble shooting the breakout board. Most likely the common wire.

I used the same common wire on the right side, I just transplanted the Din cables to the other side, and it was resetting even when not in contact with the reset pin, I assume it was a safety feature of either the board or the machine supplying power to it detecting a short when the pins were shorted together.

What we did with ours, is we connected 3.3V from the MSP Launchpad to the common on an arcade button, and then the NO side to the digital I/O pin we’re using. The MSP Launchpad has pull down resistors unlike the RIO which has pull up resistors. So you need to provide the digital input with 3.3V instead of pulling it to ground like the Roborio.

To generate an LED we connect the anode to the digital output pin with the appropriate resistor for 3.3V and the Cathode to ground.

Be careful, that you only use 3.3V as we fried one of ours thinking it was a 5V device.