Skip to content

Troubleshooting Ball Device Issues

If you got problems in general we first recommend to read our troubleshooting guide. Here we go into details for ball devices (troughs, plungers, lock devices and more) in particular.

Add debug

First, add a debug: true entry into your trough config in the ball_devices: section. Then when you run with verbose logging (-v), you'll get extra debugging information in the log.

Received unexpected ball

You might get a line in your log telling your that the device received an unexpected ball. This is usually not an issue. It means that the device did not expect the ball. For instance, if a ball drains into a trough or jumps into the shooter that is unexpected for the device. In most cases you will see this message when a ball drained.

So what are expected balls? In modern machines the trough ejects a ball into the shooter lane in which case the shooter lane device expects the ball from the trough. This is connected to ball tracking and retry behavior of devices.

Ball Count Does Not Match

If your log file shows a number of balls contained in your trough that doesn't match how many balls you actually have, that could be:

  • You didn't add all the ball switches to the ball_switches: section of the trough configuration
  • You're using a physical machine but a switch isn't adjusted properly so the ball is not actually activating it. (Seriously, we can't tell you how many times that's happened! We've also found that on some machines, if you only have one ball in the trough that the single ball isn't heavy enough to roll over the top of the eject coil shaft. In that case we just add a few more balls to the machine and it seems to take care of it.) Either way, if you have a ball in the trough, the switch entry in your log should show that the switch is active (State:1), like this:
    2014-10-27 20:05:29,891 : SwitchController : <<<<< switch: trough1, State:1 >>>>>

If you see State:1 immediately followed by another entry with State:0, that means the ball isn't activating the switch even though it might be in the trough.

If you got problems with some switches also add debug: true to those as it will give to more insights into the intentions of those devices. Same will work for flippers, coils, lights, servos, steppers and more. See general debugging section for details.

Run MPF with verbose flag

See general debugging section for details. TLDR: run mpf both -t -v -V.

Report Your Issue and Ask For Help

If you cannot find the issue yourself please prepare some information about your issue according to our troubleshooting guide and ask in our forum.

Consider Improving the Documentation

Did you solve your issue but found that some relevant information in the documentation is missing or should be linked/located elsewhere? Either tell us in the forum or consider improving the documentation yourself to save future users some troubles the same way others saved you some troubles by writing this documentation.

Something missing or wrong? You can fix it!

This website is edited by people like you! Is something wrong or missing? Is something out of date, or can you explain it better?

Please help us! You can fix it yourself and be an official "open source" contributor!

It's easy! See our Beginner's guide to editing the docs.

Page navigation via the keyboard: < >

You can navigate this site via the keyboard. There are two modes:

General navigation, when search is not focused:

  • F , S , / : open search dialog
  • P , , : go to previous page
  • N , . : go to next page

While using the search function:

  • Down , Up : select next / previous result
  • Esc , Tab : close search
  • Enter : go to highlighted page in the results