I need a dev board recommendation. I’m trying to finish up a project that has an array of sensors: two flow meters, two solenoids, a temperature probe, a thermometer and humidity sensor, three pressure sensors, and a I2C LED display.
The solenoids require 12V, so opening and closing them is done through a relay. Which means, I have two output pin requirements. The pressure sensors are 5V analog. So I have a breakout ADC running through I2C with the LED. I also have two buttons, that need to be run through an interrupt.
So I have, at the end, needs for:
- 6 additional input pins, 4 of which need EXTI (the flow meters and buttons)
- 2 output pins
- Pins need to be 5V tolerant
So, depending on the board, 10 usable GPIO pins
I went through what I’ve got laying around the house:
- Nano (ATmega328) and Uno -> Out because only 2 pins for interrupt
- Pro Micro -> Out because 2 of the 5 interrupt pins are SCL/SDA, needed for I2C
- NodeMCU 8266 -> Out because only really 9 GPIO pins, and I need 10… and of the 9, it seems half boot HIGH
- Particle Argon -> Would work, but kinda pricey, and don’t want to burn it up testing
So I’m looking for something, preferably on the cheaper side (than a particle), since this is just prototype, that I can burn up and not be sad. If none exists, I’ll just use the particle.
Anyone got a recommendation? A Nano 33 would probably work, but it shipped is about the same price as the argon, and I don’t have to wait for the argon to ship, as its already here.