Pololu Wixel User Manual
Page 18
9. The speed of the blinking is determined by the blink_period_ms parameter. The units of this parameter are
milliseconds (ms). Try changing blink_period_ms to 100 by double-clicking on the number and typing “100”.
You can now write the new configuration to the Wixel by clicking the “Write to Wixel” button. After the writing
is done and the app is running, you should see the red LED blinking 5 times faster than it was before.
10. The Wixel Configuration Utility can also read the settings from the Wixel. To demonstrate this, close the
Wixel Configuration Utility, reopen it, and select your Wixel. Since the Auto Read checkbox is checked by
default, and there is an application on the Wixel, the Wixel Configuration Utility will attempt to read the Wixel’s
settings. If you have not yet opened the correct app, a dialog box like the one below will pop up:
If Auto Read is enabled when you select a Wixel with an app on it, then you might be prompted
you to open the App File.
11. To read the settings from a Wixel, you will need to open the app that is currently on the Wixel. Click the
“Open” button in the dialog, and select example_blink_led_v1.0.wxl.
It is necessary to open the app file that you originally loaded onto the Wixel because the file
contains metadata required to interpret the settings contained in the Wixel’s flash memory. If you
open a different app file, even a different version of the same app, your settings will likely be
corrupted. In this case, a warning dialog box will pop up to warn you and give you some options.
Since you still have the correct app file, you should not see that dialog now.
12. After you open the Wixel App file, the Wixel Configuration Utility will read the Wixel and compare its
contents to what is in the app. You will then see the Wixel’s settings displayed on the right: blink_period_ms
should be 100. Note that the number 100 is displayed in bold. This is because it differs from the default setting,
which is 500. You can reset it to the default at any time by right-clicking on the number and selecting “Reset to
Default Value”.
After completing this tutorial you should be comfortable with writing apps to the Wixel and reading back the settings.
This is all you need to know in order to configure your Wixels. When you load a real application, such as the
Pololu Wixel User's Guide
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3. Getting Started
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