# I2c lcd only showing upper blocks nothing else **URL:** \ **Category:** Displays\ **Created:** [January 19, 2022, 5:10am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753 "2022-01-19T05:10:05Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![rajaarin](https://avatars.discourse-cdn.com/v4/letter/r/58f4c7/32.png) [@rajaarin](https://forum.arduino.cc/u/rajaarin)\ **Post date:** [January 19, 2022, 5:10am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/1 "2022-01-19T05:10:05Z")
I m making a distance measurement using arduino , ultrasonic sensor and i2c lcd. But after installing code also nothing visible on my screen only upper blocks is visible. THIS IS MY CODE ```cpp #include // Library for I2C communication #include // Library for LCD LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2); // Change to (0x27,16,2) for 16x2 LCD.my address is (0x3F) int trigPin = A0; int echoPin = A1; long distance; long distanceInch; long duration; void setup(){ lcd.begin(); lcd.backlight(); pinMode(trigPin, OUTPUT); pinMode(echoPin, INPUT); lcd.setCursor(0,0); lcd.print(" WELCOME TO"); lcd.setCursor(0,1); lcd.print(" MKINVENTIONS"); delay(2000); } void loop() { ULTRASONIC(); lcd.clear(); lcd.setCursor(0,0); lcd.print("DISTANCE CM:"); lcd.print(distance); lcd.setCursor(0,1); lcd.print("DISTANCE INCH:"); lcd.print(distanceInch); // lcd.setCursor(0,1); // lcd.print("DISTANCE MM:"); // lcd.print(distanceInch); } void ULTRASONIC(){ digitalWrite(trigPin, LOW); delayMicroseconds(2); digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin, LOW); duration = pulseIn(echoPin, HIGH); distance = duration*0.034/2; distanceInch = duration*0.0133/2; } ``` ![1642568957192379127998923385817](https://europe1.discourse-cdn.com/arduino/original/4X/7/4/9/7491813f03d8baa2e436a072189a519e12b916bb.jpeg) ---
**Author:** ![LarryD](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/larryd/32/215550_2.png) [@LarryD](https://forum.arduino.cc/u/LarryD)\ **Post date:** [January 19, 2022, 5:23am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/2 "2022-01-19T05:23:02Z")
Turn the LCD contrast potentiometer down to the point where the blocks **just appear**. ---
**Author:** ![rajaarin](https://avatars.discourse-cdn.com/v4/letter/r/58f4c7/32.png) [@rajaarin](https://forum.arduino.cc/u/rajaarin)\ **Post date:** [January 19, 2022, 6:04am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/3 "2022-01-19T06:04:57Z")
I did that also then also its nt working only upper blocks r there . Even though I have tried a simple hello world cold also but that's also not showing ---
**Author:** ![LarryD](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/larryd/32/215550_2.png) [@LarryD](https://forum.arduino.cc/u/LarryD)\ **Post date:** [January 19, 2022, 6:05am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/4 "2022-01-19T06:05:48Z")
What address is your I2C LCD ? ---
**Author:** ![rajaarin](https://avatars.discourse-cdn.com/v4/letter/r/58f4c7/32.png) [@rajaarin](https://forum.arduino.cc/u/rajaarin)\ **Post date:** [January 19, 2022, 6:21am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/5 "2022-01-19T06:21:09Z")
0\*27 ---
**Author:** ![rajaarin](https://avatars.discourse-cdn.com/v4/letter/r/58f4c7/32.png) [@rajaarin](https://forum.arduino.cc/u/rajaarin)\ **Post date:** [January 19, 2022, 7:10am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/6 "2022-01-19T07:10:41Z")
please help regarding this issue ---
**Author:** ![UKHeliBob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ukhelibob/32/215663_2.png) [@UKHeliBob](https://forum.arduino.cc/u/UKHeliBob)\ **Post date:** [January 19, 2022, 7:43am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/7 "2022-01-19T07:43:38Z")
Other post/duplicate DELETED Please do NOT cross post / duplicate as it wastes peoples time and efforts to have more than one post for a single topic. Continued cross posting could result in a time out from the forum. Could you also take a few moments to [[url=https://forum.arduino.cc/index.php?topic=710766.0]](https://forum.arduino.cc/t/please-check-the-troubleshooting-guide-before-posting-here/52209/2)Learn How To Use The Forum[/url]. Other general [help and troubleshooting advice can be found here.](https://forum.arduino.cc/t/please-check-the-troubleshooting-guide-before-posting-here/52209/2) It will help you get the best out of the forum in the future. ---
**Author:** ![markd833](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/markd833/32/1186928_2.png) [@markd833](https://forum.arduino.cc/u/markd833)\ **Post date:** [January 19, 2022, 7:52am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/8 "2022-01-19T07:52:01Z")
Have you tried the LCD example(s) that came with the LCD library? Did they work? ---
**Author:** ![Paul\_B](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/paul_b/32/216376_2.png) [@Paul\_B](https://forum.arduino.cc/u/Paul_B)\ **Post date:** [January 19, 2022, 7:53am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/9 "2022-01-19T07:53:00Z")
OK, not sure why Larry is barking up the wrong tree (and Mark just noted, sadly has **no** idea!). You are seeing the "blocks" on the first line. That means your contrast control is set **more-or-less** correctly - good enough in any case. What the "blocks" **mean** is that you are not "talking" to the display. Why? Well, using a completely _obsolete_ library, sad to say! 😟 OK, use the Library Manager in the IDE to install Bill Perry's "HD44780" library and then run from that library, the examples \> ioClass \> hd44780\_I2Cexp \> I2CexpDiag sketch to find the details for and test your display. You can then work from one of the sketches in that directory to build what you need to. 😁 ---
**Author:** ![outbackhut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/outbackhut/32/1099892_2.png) [@outbackhut](https://forum.arduino.cc/u/outbackhut)\ **Post date:** [June 23, 2022, 2:11am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/10 "2022-06-23T02:11:34Z")
I wouldn't DREAM of using the HD44780 library. I have tried that one, but it just ISN'T as good OR easy to use as the one @rajaarin is currently using. @rajaarin, your screen will NEVER display anything with ```cpp lcd.begin(); ``` You MUST use ```cpp lcd.init(); ``` Change that and it should work. ---
**Author:** ![UKHeliBob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ukhelibob/32/215663_2.png) [@UKHeliBob](https://forum.arduino.cc/u/UKHeliBob)\ **Post date:** [June 23, 2022, 6:35am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/11 "2022-06-23T06:35:49Z")
Whether you use lcd.init() or lcd.begin() depends entirely on which library you are using As usual, the Devil is in the detail ---
**Author:** ![outbackhut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/outbackhut/32/1099892_2.png) [@outbackhut](https://forum.arduino.cc/u/outbackhut)\ **Post date:** [June 23, 2022, 8:50am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/12 "2022-06-23T08:50:05Z")
@UKHeliBob True. The library in rajaarin's code uses `lcd.begin();` though, not `init();`. ---
**Author:** ![UKHeliBob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ukhelibob/32/215663_2.png) [@UKHeliBob](https://forum.arduino.cc/u/UKHeliBob)\ **Post date:** [June 23, 2022, 11:24am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/13 "2022-06-23T11:24:45Z")
I must have missed where we established exactly which library was being used ---
**Author:** ![outbackhut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/outbackhut/32/1099892_2.png) [@outbackhut](https://forum.arduino.cc/u/outbackhut)\ **Post date:** [June 24, 2022, 12:27am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/14 "2022-06-24T00:27:52Z")
![image](https://europe1.discourse-cdn.com/arduino/original/4X/5/8/d/58d857827086841456cd49e207c0d6703dc49ef6.png) ---
**Author:** ![UKHeliBob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ukhelibob/32/215663_2.png) [@UKHeliBob](https://forum.arduino.cc/u/UKHeliBob)\ **Post date:** [June 24, 2022, 6:45am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/15 "2022-06-24T06:45:11Z")
If that was intended to show exactly which library is being used then it was a failure. All it shows is that the library is named LiquidCrystal\_I2C, of which there are several ---
**Author:** ![outbackhut](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/outbackhut/32/1099892_2.png) [@outbackhut](https://forum.arduino.cc/u/outbackhut)\ **Post date:** [June 24, 2022, 7:14am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/16 "2022-06-24T07:14:21Z")
Yeah, I guess. I just assumed it was the most used one. ---
**Author:** ![system](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/system/32/1140315_2.png) [@system](https://forum.arduino.cc/u/system)\ **Post date:** [December 21, 2022, 7:15am UTC](https://forum.arduino.cc/t/i2c-lcd-only-showing-upper-blocks-nothing-else/948753/17 "2022-12-21T07:15:19Z")
This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.