micronEC

Simple, easy-to-use hardware counter. Raspberry Pico basis. 16x2 LCD panel. micronEC.

1. Name

For micronEC, the name says what it does. "EC" stands for Easy Counter. "EC" can also be read as "easy", which alludes to the utility.

2. Hardware

Required Hardware:

• Raspberry Pi Pico W
• 16x2 LCD with PCF8574* backpack
• [In standard configuration: 2 Hardware Buttons]

Measured power consumption (Raspberry Pi Pico W, LCM1602 LCD panel, PCF8574T backpack, generic button):

• ~40mA in idle mode, + ~2mA when handling button events
• ~43mA at startup

3. Hardware preparation & Software installation

3.1 Hardware preparation

If you've got all the hardware stuff, let's start building your micronEC!

The only thing to say here are the standard pinouts (all of these can be changed, see 3.2 Software installation).

A pinout sheet can be found here.

Component	Pin (name) on component	Pin name on Pico	Pin number on Pico
LCD backpack	SDA	GPIO0	1
LCD backpack	SCL	GPIO1	2
LCD backpack	GND	GND	3
LCD backpack	VCC	VBUS¹	40¹
Button 1	Pin 1	GPIO2	4
Button 1	Pin 2	GND	3
Button 2	Pin 1	GPIO3	5
Button 2	Pin 2	GND	3

[¹]: This pin provides 5V to the backpack - but only when the pico itself get's its power via USB.

3.2 Software installation

1. To get your Raspberry Pi Pico W ready for micronEC, make sure you've already installed microPython on it.
2. Clone this repository to your local filesystem.
3. Open Thonny
4. Open the following files:
   • counter.py - library providing counting stuff
   • lcd_driver.py - the lcd driver (working for PCF8574*)
   • lcd_screen.py - library providing a class for displaying counters
   • welcome.py - library providing a welcome/startup screen shown on the lcd
   • micronec.py - the main.py
5. In micronec.py, you can make changes as you need to - it's all commented and explained
6. (Connect yout Raspberry Pi Pico to your computer)
7. Upload all previously opened files (except the micronec.py!) to the Pico
8. Now decide:
   • if you just want a preview, upload the micronec.py as it is (no renaming) and press F5 to run.
   • ONLY DO THAT IF YOU KNOW WHAT YOU ARE DOING: if you want to use that version for production, upload the micronec.py as main.py
     • WARNING: the pico always runs the main.py file on startup, so there's no chance to connect to it via USB. If you do so, and want to change things later, you have to completely reinstall microPython on your Pico and all previously uploaded files will be gone. ONLY DO THAT IF YOU KNOW WHAT YOU ARE DOING.
9. Have fun!

4. License

micronEC is licensed under GPLv3, a copy of it can be found in LICENSE.md.