(still work in progress, not fully tested)
A smart MIDI box based on a STM32 "blue pill" microcontroller (STM32F103C8T6).
Software is hosted on Github: https://github.com/retro16/MidiBox
Uses a HD44780 16x2 LCD screen with the usual I2C converter.
The interface is made of 4 push buttons arranged in a directional pad (up, down, left, right).
A SD card can be attached for more features.
12V 50Ω solenoid driver. Can be chained to control more than eight solenoids.
The solenoid driver uses a shift register with a latch to control its outputs such that a singe microcontroller (e.g. Arduino) can control large amounts of solenoids whilst only requiring 3 output pins.
- Too big thermals reliefs on; U1-pin8, R12..R15, R24..R27 (they cool too quickly while solder...
This my first take on an Arduino Nano PLC(ish) device.
It uses standard discrete components and thus is rather cheap to build.
But discrete components do take up a bit more space.
The inputs can accept up to 24v and are connected to the analoge pins, using optocouplers the inputs are electrically isolated
from the Arduino.
The outputs uses relays, the outputs from the relay uses an external sourc...