The LiquidCrystal-I2C sketch wont compile and gives this error ..no matching function for call 'LiquidCrystal::LiquidCrystal(int)'
The 'regular' Liquid Crystal sketch in the same Examples folder compiles OK - no errors.
All the support .c and .h files are in the new (I2C) LiquidCrystal library folder and the regular LiquidCrystal compiles.
Any ideas?
LiquidCrystal I2C
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Please be positive and constructive with your questions and comments.
- adafruit_support_bill
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Re: LiquidCrystal I2C
Did you remove the old LiquidCrystal Library?
- platypus
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Re: LiquidCrystal I2C
Yes eventually, but first I just renamed the folder and later decided to place this folder within another folder.
Then it worked as the compiler could not see it.
My bad - should have followed your notes to the letter. Thanks for your reply.
Then it worked as the compiler could not see it.
My bad - should have followed your notes to the letter. Thanks for your reply.
- platypus
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- Joined: Thu Jan 19, 2012 1:47 am
LiquidCrystal I2C - background light intensity
Do you have a method to reduce the intensity of the background light?
The Contrast only affects the characters leaving the "blind your eye" background light.
I read somewhere that pin 15 via a resistor/pot might work.
If so, can you recommend a suitable trimpot size and or procedure to effect a reduced intensity level?
The Contrast only affects the characters leaving the "blind your eye" background light.
I read somewhere that pin 15 via a resistor/pot might work.
If so, can you recommend a suitable trimpot size and or procedure to effect a reduced intensity level?
- adafruit_support_bill
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Re: LiquidCrystal I2C
You would probably need a few hundred ohms or so, depending on how much you want to dim it. It would be tough to get at on that board though without de-soldering the display. Another option would be to put it behind a smoked acrylic faceplate.
- platypus
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Re: LiquidCrystal I2C
Thanks, that's exactly where it's going - behind dark tinted 3mm polycarbonate. However I still want to dim the backlight.
But is it pin 15 that should be broken - easy to do before assembly. The pot can be mounted between the screen and I2C pcb as I have lifted the I2C board 3mm using two short pieces of heat shrink at the end terminals before soldering from the center outwards. This also gives a nice space between the two boards.
For anyone there who is interested, I had to stop the annoying update blink screen refresh by this method - if anyone knows of another I would be interested.
In void loop()
lcd.setCursor(0,0); //sets beginning of line 1
lcd.print( your code for line 1);
lcd.setCursor(0,1); //sets beginning of line 2
lcd.print(your code for line 2);
// no more blink
Comment - this causes a refresh of each line without any blinking, giving a nice update of the sensor data.
If lcd.clear();
is used the whole display will blink annoyingly - at least with this 2 line charactor lcd screen.
With my older Freetronics lcd screens that use 6 lines there is no blinking. Different tech.
But is it pin 15 that should be broken - easy to do before assembly. The pot can be mounted between the screen and I2C pcb as I have lifted the I2C board 3mm using two short pieces of heat shrink at the end terminals before soldering from the center outwards. This also gives a nice space between the two boards.
For anyone there who is interested, I had to stop the annoying update blink screen refresh by this method - if anyone knows of another I would be interested.
In void loop()
lcd.setCursor(0,0); //sets beginning of line 1
lcd.print( your code for line 1);
lcd.setCursor(0,1); //sets beginning of line 2
lcd.print(your code for line 2);
// no more blink
Comment - this causes a refresh of each line without any blinking, giving a nice update of the sensor data.
If lcd.clear();
is used the whole display will blink annoyingly - at least with this 2 line charactor lcd screen.
With my older Freetronics lcd screens that use 6 lines there is no blinking. Different tech.
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: LiquidCrystal I2C
Pin 15 should work. But if it is an RGB backlight, the colors may shift a bit as you dim it. To balance the colors, you would need individual trim-pots on pins 16, 17 & 18.
- platypus
- Posts: 45
- Joined: Thu Jan 19, 2012 1:47 am
Re: LiquidCrystal I2C
I used the 1K trimpot that came with the white on blue 2 line character screen.
I cut the pin 15 header - as I had lifted it 3mm it was easy to just take out a piece to break the line. Then just added the trimpot across the board terminals - works perfectly.
Thanks for your help.
I cut the pin 15 header - as I had lifted it 3mm it was easy to just take out a piece to break the line. Then just added the trimpot across the board terminals - works perfectly.
Thanks for your help.
-
- Posts: 4
- Joined: Thu Feb 07, 2013 9:18 am
LiquidCrystal I2C
Hallo,
Can anybody help me? I have plugged converter from I2C to 4bit for LCD, I implemented your library and compile is OK. But LCD not show characters and backlight blinking chaotic. The wires are plugged by right. Which format I must write the number of adress I2C to sketch. A7 or 0xA7? I don´t know where is problem.
Can anybody help me? I have plugged converter from I2C to 4bit for LCD, I implemented your library and compile is OK. But LCD not show characters and backlight blinking chaotic. The wires are plugged by right. Which format I must write the number of adress I2C to sketch. A7 or 0xA7? I don´t know where is problem.
Last edited by zdendule on Thu Feb 07, 2013 11:33 am, edited 1 time in total.
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: LiquidCrystal I2C
Post photos showing the front and back and all your connections and we will check it out.
-
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- Joined: Thu Feb 07, 2013 9:18 am
Re: LiquidCrystal I2C
OK, thank you. There are photos.
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: LiquidCrystal I2C
That doesn't look like one of our display backpacks.
-
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Re: LiquidCrystal I2C
Yes, I firstly found interface on web and past it I found library for it. But during the search I found your forum.
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: LiquidCrystal I2C
You should contact the manufacturer. Unless their hardware implementation is identical to ours, there is no guarantee that our library will work.
Please be positive and constructive with your questions and comments.