I am building a project that requires an lcd screen. I've followed several tutorials and multiple threads on this forum but no one else seems to have the same problem I am having. I've used the following tutorials' diagrams to hook up the lcd to the arduino
I've also made sure to change "LiquidCrystal lcd(12, 11, 5, 4, 3, 2);" to "LiquidCrystal lcd(12, 11, 10, 9, 8, 7);" because those are the pins I'm using and have tried those same pins backwards and forwards in addition to trying using all the digital pins (which compiled just fine) backwards and forwards but still nothing other than a row of blocks. The pot for contrast works just fine and the backlight is working fine also.
Also some sites are saying it mattters which pin goes to what, others are saying it doesn't matter which pins you use so long as you set up the code correctly and others are saying it depends on what library. I dunno what to believe at this point.
I'm pulling out hair, it's driving me insane. I know why mad scientists in movies are usually partly bald now.
I am building a project that requires an lcd screen. I've followed several tutorials and multiple threads on this forum but no one else seems to have the same problem I am having....
Surely you are kidding. Have you tried searching for the term LCD Blocks using the search box at the upper right part of this page?
I said I've already implemented the troubleshooting in the other threads in this forum where people have a similar problem to mine and no matter how I wire the darn thing according to said threads and psosts I'm still only getting a row of solid blocks.
I've followed several tutorials and multiple threads on this forum but no one else seems to have the same problem I am having
Floresta If you're just here to cherry-pick quotes and nit pick about word usage then please leave me alone. This is my first time here and you're very poorly representing the arduino community. I'm here for help with a project, not a flame war.
Anyway, Paul__B here's the code I'm using:
// include the library code:
#include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// 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);
}
And if I linked the images correctly (fingers crossed) here's my wiring and the solder job I did on the lcd. I'm using a Mega 2650. I can retake these if you want
Floresta If you're just here to cherry-pick quotes and nit pick about word usage then please leave me alone.
I'm sorry if I offended you but it is impossible to offer meaningful help with incomplete information. Paul is probably sleeping now so I am all you have for a few hours.
Your first photograph indicates that your soldering is likely to be at least one part of your problem. Take a look at the information here for some tips.
Your second photo isn't much help because we have to be able to see both ends of each wire in order to trace them.
Your third photo is has the right content but it is still hard to follow the wires. Using different colors for wires in adjacent pins would help as would taking the photo from further away to reduce the parallax effect.
Fix the soldering first and you may not have to reshoot the photos.
Don
EDIT: "And if I linked the images correctly (fingers crossed) "
You can check out your links before posting by using the [Preview] button.
floresta:
I'm sorry if I offended you but it is impossible to offer meaningful help with incomplete information. Paul is probably sleeping now so I am all you have for a few hours.
I generally do not have that luxury just after midday. Even on Saturday I am generally out shopping for the week.
Well, those photos do not look like (outdoor) daylight to me. The focus is indifferent in the second two.
If I may give you a suggestion, use a proper camera with a zoom lens, at least a metre away and use maximum zoom.
As best as I can see, your VDD on pin 2 is not connected, nor is RW and V0, RS and "E" are dubious.
Floresta Sorry i got offended it's just that I recently got off an argument online where someone said some things that were hurtfully unnecessary and I was still paranoid.
As for my connections, let me figure out a way to hook up the wires so that they're straight and there aren't any curves to interpret. Tape will probably be involved. Right now the yellow wires are for data, red/orange are positive and should be connected to the positive rail, and blue/purple/black are my negatives and should be connected to the negative rail, and green is exclusively for the VO (I only have one green jumper in my kit)
Also I thought that RW VO RS and E were connected? Unless you mean I connected them to the wrong spots?
Also the pictures are taken from my galaxy 5. The focus on it is terrible and I have to shine a flashlight on something for it to focus at that difference. I wish there was just a slider on the camera app that lets you manually adjust the focus.
Gozeraye:
Also the pictures are taken from my galaxy 5. The focus on it is terrible and I have to shine a flashlight on something for it to focus at that difference. I wish there was just a slider on the camera app that lets you manually adjust the focus.
I have repeated twice that it is necessary to take the photos in outside daylight, sunlight but not direct sun. How would a torch help in daylight?
I specify that for an extremely good reason. Without a high quality camera (or at least three proper floodlights), it is a waste of time to take such photos indoors.
Your pictures seem to have disappeared.
Oh - I see - crap hosting site.
Gozeraye:
Also I thought that RW VO RS and E were connected? Unless you mean I connected them to the wrong spots?
You may think they were, but they do not really look to us as if the connections are actually soldered.
I had this problem with my Mega board and I discovered that I had connected the data line to the wrong pins I used A3,A4, A5 etc when I should have used the the pins marked 4,5,6, etc.
Your solution is not really relevant since his photograph shows that he is not using the 'analog' pins as you did.
On the other hand it did get me to look at the connections again and it appears that he may have them exactly wrong.
It's just too bad that the perpetrators of the example sketch failed to include a simple comment that would help prevent this sort of mistake.
According to the photograph his RS pin is connected to what looks like pin 7 of his Mega, and the rest of the connections connect to successively higher numbered pins. This means that the constructor should look like this . . .
My current hookups and current understanding of how the wires should be hooked up are as follows
VSS to Ground
VDD to 5v
VO to middle terminal of a powered potentiometer (which is plugged into 5v)
RS to PMW 7
RW to Ground
E to PMW 8
D4 to PMW 9
D5 to PMW 10
D6 to PMW 11
D7 to PMW 12
A to 5v (some people have a resistor between these two)
K to Ground
Are any of the above connections wrong or questionable?
For power and ground I am using the power and ground rails on the breadboard. I am still using the code I posted earlier, which is
// include the library code:
#include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(7, 8, 9, 10, 11, 12);
void setup() {
// set up the LCD's number of columns and rows:
lcd.begin(16, 2);
// 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);
}
you may think they were [soldered], but they do not really look to us as if the connections are actually soldered.
Also, I don't understand how some of the connections arent soldered??? I put solder on all of them didn't I? My current understanding is that when you solder on pins you are trying to connect the metal of the pin to the conductive surface it is resting on, thus adding them to the circuit.
Gozeraye:
Also, I don't understand how some of the connections arent soldered??? I put solder on all of them didn't I? My current understanding is that when you solder on pins you are trying to connect the metal of the pin to the conductive surface it is resting on, thus adding them to the circuit.
Ah, now there's the point.
Soldering is not "putting solder on them".
Soldering is making sure that the solder is evenly adherent to the metal on both pieces, which is indicated by forming a fillet between the two.
(The appearance on the right.)
What is abundantly clear is that your solder joins do not look like that! In fact, on the pins cited, the solder does not seem to be in contact with the pin at all, but instead forming a ball next to it.
Which I cannot include as an image here to remind you because "Google Drive" deliberately prevents linking.
Are any of the above connections wrong or questionable?
The connections are correct.
For power and ground I am using the power and ground rails on the breadboard
Be careful. Make sure you understand that the gaps near the center of the blue and red lines next to your power rails correspond to gaps in the power rails themselves. This was not a problem in your earlier setup, make sure you have not introduced one now that you have rewired things.
In reference to your soldering, did you look at the link I provided in reply #6.
Which I cannot include as an image here to remind you because "Google Drive" deliberately prevents linking.
What site would be better for linking images to this forum? Google drive is just my go-to so I've never really looked into anything else.
The connections are correct.
Okay so at least I know that I've got the theory down and I know that my issue is with my execution. I'm going to go tape my arduino and my breadboard down on a piece of cardboard, use only LONG jumper wires to make these connections one at a time, then tape the wires down so they make linear paths between the connections, then take the cardboard circuit sandwich outside and snap a picture and hopefully that fixes my camera issue.
Soldering is making sure that the solder is evenly adherent to the metal on both pieces, which is indicated by forming a fillet between the two.
So if I am understanding correctly, the issue with having a "bubble" of solder on each pin like I have is that you cannot see the state of the pin when it's completely covered up?
Gozeraye:
So if I am understanding correctly, the issue with having a "bubble" of solder on each pin like I have is that you cannot see the state of the pin when it's completely covered up?
It just looks as if the "bubble" is sitting next to the pin, but not actually connecting to it.
I think imgur seems to be largely reliable - but you have to get the link to the actual picture. I tried to extract that on your post from Google Drive, but it keeps moving it!
Okay, so I'm not sure if I just got my wires crossed (either literally or figuratively speaking) but it's magically working now. I've taken the connections apart and put them together again several times to make sure I didn't just get incredibly lucky and it still works. I'm going to save the connections list that was made in an earlier reply as a personal cheat sheet.
I also had to re-solder the screen. It looks much neater now.
Thanks guys!
Also do I need to mark this thread as "resolved" or is it fine if I just leave it?
Gozeraye:
Okay, so I'm not sure if I just got my wires crossed (either literally or figuratively speaking) but it's magically working now. I've taken the connections apart and put them together again several times to make sure I didn't just get incredibly lucky and it still works. I'm going to save the connections list that was made in an earlier reply as a personal cheat sheet.
I also had to re-solder the screen. It looks much neater now.
Thanks guys!
Also do I need to mark this thread as "resolved" or is it fine if I just leave it?
It is probably an intermittent in the crappy solder job.
It isn't the worst I've seen but I would not trust it.
Soldering is not about gobbing solder on.
It is about flowing solder into both metal surfaces.
You might still consider doing them correctly.
Use some solder wick or a solder sucker to remove the
mess you have.
I assume you have solder with flux?
Heat both surfaces with a clean tinned iron until it reaches
the temperature that solder melts when touching the surfaces,
not just the iron. ( I do often touch a tiny amount of solder
to the iron, right at the point where it makes contact with
the pin. I then hold the sold on the pin, not the iron.
This gets a tiny amount of flux between the iron and pin to
get better conduction of heat ).
The solder should flow into the joint, making the meniscus
as shown in the picture from Paul.
If it looks like a ball, it is too much solder or it hasn't flown
onto the surfaces properly. Remove the solder and try again.
Soldering is a skill. It is not real hard to learn but not always
obvious to the beginner why a bad joint is a bad joint.
Dwight
Even on Saturday I am generally out shopping for the week.
