Hacks & Upgrades

Speeding up many requests from Raspberry Pi to CRICKIT

If your project is making a large number of requests from your Raspberry Pi to CRICKIT, the speed of the I2C connection between boards may be an issue. Fortunately this can be changed.

For the best performance, you'll want to consider tweaking the I2C core to run at 1MHz. By default it may be 100KHz or 400KHz

To do this edit the config with sudo nano /boot/config.txt

and add to the end of the file

dtparam=i2c_baudrate=1000000

Brown Outs?

The power supply on the Crickit will let you draw 4 Amps at once, which is a lot. But perhaps you are turning on all the motors at once, causing the power supply to flicker? An extra large capacitor on the 5V and GND pads may help smooth out that power draw!

Use a large electrolytic capacitor, rated for 10V or higher. Even though the power supply is 5V, you may think you can use a 6.3V capacitor, but you want at least 2x the voltage rating if possible so stick to 10V!

4700uF 10v Electrolytic Capacitor

PRODUCT ID: 1589
This Big Freaking Capacitor is just the trick when you have a lot of current sloshing around your project. They'll help smooth out voltage spikes by providing a little buffering....
$1.95
IN STOCK

Connect the capacitor using the NeoPixel terminal blocks. The 5V and GND lines are shared across the board so even if its a DC motor or servo causing the issues, this will help! It's just the most convenient place to attach a large capacitor because the two terminal blocks are nicely spaced.

Connect the capacitor using the NeoPixel terminal blocks. The 5V and GND lines are shared across the board so even if its a DC motor or servo causing the issues, this will help!

 

Connect the Positive (longer leg) to 5V and the Negative (shorter leg) to GND

This guide was first published on May 16, 2018. It was last updated on May 16, 2018. This page (Hacks & Upgrades) was last updated on Aug 16, 2019.