Velosats Moderators: adafruit_support_bill, adafruit

[adafruit_support_bill]

We have a step-by-step guide here: https://learn.adafruit.com/i2c-spi-lcd- ... no-i2c-use

[animefruit]

Ok. But what are those blue screw things? How do you connect those? Do I need some sort of special wires for those blue screw things?

[adafruit_support_bill]

The blue screw terminals are included with the kit. They are optional. You can solder your wires directly to the holes if you prefer.

[animefruit]

So is this lcd thing just a backpack? Or does it also come with an lcd?

[animefruit]

If so, will big lcds like 20 * 4 lcds work for this backpack?

[animefruit]

So is this lcd thing just a backpack? Or does it also come with an lcd?

[animefruit]

How do I solder this backpack? Just got it today.

[adafruit_support_bill]

There are instructions in the guide: https://learn.adafruit.com/i2c-spi-lcd- ... k/assembly

[animefruit]

I tried to solder the backpack to the lcd, but it seems like it didn’t stick. Do you know how I can fix this?

[adafruit_support_bill]

Please read through our soldering guide here: https://learn.adafruit.com/adafruit-gui ... -soldering
These pages cover preparation and making the joint:
https://learn.adafruit.com/adafruit-gui ... reparation
https://learn.adafruit.com/adafruit-gui ... lder-joint

And this page has some tips on fixing problems: https://learn.adafruit.com/adafruit-gui ... n-problems

[animefruit]

Ok. So I connected my lcd and all that. And now I uploaded the Adafruit_LiquidCrystal->HelloWorld_i2c sketch and it blinks like it should, but it doesn't show the text.I also tried to make it display the amount of collomns of my lcd, which is 20 by 4. I also tryed removing the code of it blinking. What should I do?

Here is my code, in case that is usefull:

Code: Select all | TOGGLE FULL SIZE

/*
 Demonstration sketch for Adafruit i2c/SPI LCD backpack
 using MCP23008 I2C expander
 ( http://www.ladyada.net/products/i2cspilcdbackpack/index.html )

 This sketch prints "Hello World!" to the LCD
 and shows the time.
 
  The circuit:
 * 5V to Arduino 5V pin
 * GND to Arduino GND pin
 * CLK to Analog #5
 * DAT to Analog #4
*/

// include the library code:
#include "Wire.h"
#include "Adafruit_LiquidCrystal.h"

// Connect via i2c, default address #0 (A0-A2 not jumpered)
Adafruit_LiquidCrystal lcd(0);

void setup() {
  // set up the LCD's number of rows and columns:
  lcd.begin(20, 4);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis()/1000);

  //lcd.setBacklight(HIGH);
  //delay(500);
 // lcd.setBacklight(LOW);
  //delay(500);
}


[adafruit_support_bill]

Please post some photos showing your soldering and connections.

[animefruit]

Here are my connections of my lcd. You can see if anything looks wrong.

[animefruit]

Here is my back solder connections of my lcd.

[adafruit_support_bill]

On the front side, you have some solder spatters that should be removed. If they get loose they could cause a short circuit.

On the back side, you have several solder joints that have not flowed onto the solder pad. You should retouch those joints to make sure you have a reliable electrical connection: https://learn.adafruit.com/adafruit-gui ... tep-418537