RPUpi

Shield for RS422 over CAT5 with a Pi Zero host. It is a multidrop serial bus. I use it with RPUno or Irrigate7 with the AVR toolchain found on Raspbian, which means I can compile bare metal programs and then upload the firmware with the avrdude tool to a serial bootloader on one of the RPUno or Irrigate7 daisy-chained to the Pi Zero. The exposed network surface of Raspian on the Pi Zero is nil by default so it will need to be configured for some sort of remote access, I use SSH.

RPUpi Forum HackADay

Irrigate7

This Solar Powerd Programmable Controller board has pluggable connections for seven Latching Solenoid Drivers, seven digital I/O, two Input Capture, and four Analog inputs with current sources to power four loops. Use a 3W or 20W PV string of 36 cells to power the 12V SLA charge controller that includes simple battery management.

It is similar to the RPUno design but has some additional pluggable interfaces (e.g. IO2, ICP3, ADC4, ADC5). It’s MCU is the ATmega1284p and has Arduino-style headers that work with the RPUpi, RPUadpt, or RPUftdi shields. The embedded LT3652 solar charge controller manages battery charging and the ATmega1284p interfaces with it (see Hardware for more details).

GitHub Forum HackADay

RPUadpt

Shield for full duplex RS-422 over CAT5. Its a multidrop bus that works with serial bootloaders (e.g. optiboot, xboot… ) and avrdude.

GitHub Forum Hackaday

RPUftdi

Shield for full duplex RS-422 over CAT5 with USB for a host. Its a multidrop bus that works with serial bootloaders (e.g. optiboot, xboot… ) and avrdude.

GitHub Forum HackADay

K3

Latching Solenoid or Relay driver with three half bridge and a common half bridge that can be used to discharge a (9V/12V/24V) capacitively stored charge into a latching Solenoid or Relay coil.

K3 Forum Hack