Fletchtronics

I'm an avid hackaday.com fan. Their site was the first to get listed in the "good sites" list on fletchtronics.

Recently, hackaday took preorders for their new Bus Pirate. Being hackday, the Bus Pirate got about a thousand preorders. Being fletchtronics, I got about 20 for Bumble-B :-)

What Bus Pirate does is gives you a virtual rs232 type serial interface (such as COM* in Windows or /dev/ttyS* in Linux) to various back-end serial formats used in digital electronics like SPI or i2c or even raw pin bit-banging. So you can use a serial terminal program to test new peripheral devices quickly.

I thought, hey, I bet Bumble-B could do that. So I spoke with Dean Camera, the author of LUFA software, and asked what he thought. He pointed me to a project called userial. I downloaded and tried it, making the Makefile change to at90usb162. This project expected a native TWI library, which is present on some of the higher end at90usb chips. So I temporarily disabled all the i2c functions, and the rest of the project compiled fine.

So I can now control the pins of a Bumble-B over USB in CDC mode. Neat! I'm trying to get an SPI device working now and will update this thread with info on the devices that I can successfully connect.

It runs at 5v, so it might not work with some 3.3v devices without voltage shifting. Peripherals to test are planned for the next digikey order.

This seems like the perfect software to bundle with Bumble-B, perhaps even with a USB thumb drive with the .ini needed for Windows. I will also replace the missing i2c functions by then hopefully.

UPDATE: I2C is now working, and Bumble-B is driving a PCA9555 IO expander. See picture above.

See the Bumble-B product page for the latest version.