Anyone know of an io multiplexer shield for the Due? Looking for 24 to 48 additional io pins. Something like the Macetech Centipede that will work on 3.3v I2C. I've searched quite a bit and can't find one. I don't care if the expanded I/o pins are 3.3v or 5v from external supply. I'm trying to find a shield solution that doesn't require multiple non-shield boards. Any ideas greatly appreciated.
It looks to me like the Centipede could run at 3.3V. Try sending them an email, they might be able to sell them ready configured.
The Centipede Shield will work at 3.3V. There is a power jumper that either connects the 5V supply to the shield, or an AUX+ pin. You would need to solder a jumper wire from AUX+ to the 3.3V power pin on the shield. Additionally, the I2C pin locations on the Due are not the same as the Uno-style Arduinos. You would need to run jumper wires from A4 and A5 on the shield to the correct I2C locations.
It might be easier to simply not solder in the pass through headers, mount the Centipede Shield elsewhere, and just run 3.3V, GND, SDA, and SCL over to the shield from the Due.