I2CDriver campaign

For the past few weeks, I have been working on I2CDriver, the follow-up to SPIDriver.

I2CDriver is also going to be launched on Crowd Supply. The sign-up page is here. 

This is great, Crowd Supply is the perfect place to host a campaign for a specialized device like I2CDriver. They also have a structure for guiding you through the project creation process. I2CDriver itself is now quite well defined. The prototype has been running for some time, its firmware and graphics are stable. I'll be using the same sources and manufacturer as SPIDriver, so that part of the project is looking quite good.

But there's much more to launching a crowdfunding campaign than designing, manufacturing and shipping the product. The video must be made and the reward packages need to be decided on.

For the video, I want to demonstrate I2CDriver being used to run many I2C devices. The more the better -- the essence of I2CDriver is that it makes you incredibly powerful at I2C. So I went shopping and have ordered a bunch of things, some cheap (from Amazon) and some more expensive (from Sparkfun):

• capacitive touch sensor
• bi-color 24-LED bargraph
• 3 8x8 LED modules (hopefully these can run at 3.3 V)
• temp / humidity sensor
• 128 x 64 OLED module
• Joystiick
• Keypad
• VR IMU
• Distance sensor

The Sparkfun products are part of their Qwiic range of I2C products. It's a good idea, and I really like the extreme simplicity of the their I2C firmware. For example the keypad is read with one line of code. Nice.

As soon as these parts arrive, they will all need to be made to work with I2CDriver and then put together in a series of demonstrations. If you have any suggestions of other devices or demos, please hit [reply] and let me know!

The reward packages will include I2CDrivers, of course. The packages will also ship with I2C modules. I've been prototyping these for a couple of months now. The idea is to make the modules a standard size to cut down on cost. This also makes them easier to prototype with - a bit like Lego bricks. The actual shape is a 18x18mm square with castellated edge connectors for the four incoming wires: GND, 3.3V, SDA, SCL.

Here is the board design -- the prototype is currently on its way back to me from DirtyPCBs. There are 10 modules on this board, which will be sliced into the individual modules.In order there is:

• 7-segment 2-digit red LED
• RGB LED
• potentiometer
• buzzer
• IR receiver
• 64 Kbyte EEPROM
• 3D compass
• precision temperature sensor
• accelerometer
• real-time clock

This selection is an attempt to pick useful I2C functions - the kind of thing I'd want to use myself. The top row of 5 parts are all using an EFM8 microcontroller, so need to have firmware written to interface the I2C bus to their respective hardware. This is the same microcontroller that's used for I2CDriver, TermDriver and SPIDriver.

The plan is to put together a couple of tiers of reward packages with these modules included. It should be possible to have a package around $60 that includes an I2CDriver and 15 I2C modules. That seems like pretty good value for money.

If you have any feedback, please reply and let me know. Thanks for reading.