There are some key things to keep in mind with the TXb (and i2c busses in general):
- Powered bus boards are required when you connect three or more devices to your Teletype via i2c.
- You should only have one bus board connected to power at a time.
- Connections should be kept as short as possible using high-quality cabling (less than 3.5mm).
- There still are practical limits to having a stable i2c bus that are highly dependent on the topology of your deployment. Plan for some trial and error.
- +12V: 1 mA
- -12V: 0 mA
- +5V: 0 mA
- 20.5mm Depth
The TXb is based off of monome’s “tt-busboard” open source project. You can find it on GitHub.