Controlling a Crazyflie

This is a note on getting set up to work on a Crazyflie 2.0.

After unpacking, testing and assembling the drone, you need to get some software to talk to it.

GDB vs macOS Sierra

We probably feel downhearted if we need to use the debugger to find out what's wrong with our Ada code.

Under those circumstances, we feel even more frustrated if the debugger doesn't work!

This is exactly what has happened with gdb and macOS Sierra.

MPU9250, continued

This is a note on building support for the MPU9250 9-axis chip in the AdaPilot project (the AdaRacer hardware). It continues this report.

Invensense MPU9250 via SPI

This is a note on building support for the MPU9250 9-axis chip in the AdaPilot project (the AdaRacer hardware; the prototype board I have is subtly different from the one shown).
9-axis means it can measure each of acceleration, gyro and magnetic field values in 3 axes, which is very useful if your drone needs to know about its own motion.

Audacity 2.1.2 and El Capitan

I wanted to update Audacity, but the 2.1.2 version (from the official download site) wouldn’t run: I got can’t open application Audacity.

The application is damaged and can't be opened

I downloaded a new version of eclipseArduino (Arduino development within Eclipse). After unpacking and moving to /Applications, I get the message

"eclipseArduino" is damaged and can't be opened. You should move it to the Trash.

Huh.

After a lot of poking around, I found this:

1. Open Gatekeeper settings located in System Preferences > Security & Privacy.
2. Set Allow applications downloaded from: to Anywhere and confirm by pressing Allow From Anywhere.
3. Run the application.
4. Once the application has been successfully launched, it no longer goes through Gatekeeper; so, restore Gatekeeper settings to the default option Mac App Store and identified developers after successfully launching the application.

IO Expansion

I started checking out AdaCore's support library for STM32F4 boards, particularly to use I2C to talk to the PCF8547A IO expander (for possible use on the AdaPilot project).

I seem to have fritzed one or two of the pins on my STM32F429I-DISC0 board (now replaced by an updated version, STM32F429I-DISC1; that last character was a 0!); after some hair-pulling it turns out that one of said pins is used by the only externally-accessible I2C peripheral on the board; so, until the replacement arrives, here are some interesting facts about the PCF8547A.