Customer:
I’ve been having significant trouble getting the LCD 20x4 blue to work. I’ve followed all the instructions and verified everything multiple times, based on the guide at Nauči – Soldered Electronics (version without I2C adapter). I used your HelloWorld example from the library, but no matter what I try, I get 16x2 blank white spaces per character - no text displays. The blinking works fine. I only changed the code line to use 20x4 LCD instead of 16x2. I’m not sure what else to try.
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Originally submitted via the contact form on soldered.com on 4 September 2017. Migrated to the forum for community visibility.
Soldered Support:
Your display might have a different I2C address. Try changing the LCD object definition at the start of the code from 0x27 to 0x3F.
Customer:
I don’t see 0x27 in the code I’m using. My initialization is:
LiquidCrystal lcd(12, 11, 5, 4, 3, 2, POZOSVJETLJENJE, POSITIVE);
Should I use a different example application, even though this one is simpler?
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Soldered Support:
I see now - you’re not using an I2C adapter: Soldered: Open-Source Electronics, Boards, Sensors & Modules – Soldered Electronics
Assuming your connections are correct, I’m not sure what the issue could be. I’ll test it personally and let you know. For what it’s worth, I’d recommend getting an I2C adapter - it’s not expensive and makes using the LCD much simpler.
Customer:
Could you help me find the appropriate libraries for these products I purchased:
Light sensor with LM393 (e-radionica made) - SKU: 100027
RS-485 module (MAX485) - SKU: 101263
Smart RGB LED strip WS2812 60LED/m 5V IP20 - SKU: 100341
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Soldered Support:
Light sensor: It has a digital output (labeled DO) that you connect to any pin, which activates when a certain amount of light hits the sensor - this threshold is adjustable with the potentiometer on the board. There’s also an analog output (labeled AO) that you can connect to an analog pin to measure the voltage for more precise readings.
MAX485 uses serial communication. Here’s an example: https://arduino-info.wikispaces.com/SoftwareSerialRS485Example
Smart strip: See the Neopixel library recommendations at GitHub - adafruit/Adafruit_NeoPixel: Arduino library for controlling single-wire LED pixels (NeoPixel, WS2812, etc.) · GitHub