first of all: i'm quite new to ardiuno.
Being a webprogrammer for many years i finally got myself to get into arduino (wandering around this for quite some time)...
so... i've got myself an arduino nano and an LCD 1602 Keypad Shield and since i'm really new i'm totally lost how to connect these two... meaning wich pin on the shield i should connect to wich pin on my nano...
The example i've got for the shield is not working... meaning nothing showing on the led (wich is starting up when i plug the nano into my computer... so... i've got the power pins connected
Can anyone give me a picture or a shema what should be connected to what?
My research on google hasn't gotten me a working solution.
My goal so far is simply connecting the two and getting something showing on the LCD
Sooooooooo....
i've tested the keypad on the shield... working
i've tested the backlight pin problem and got a hard blinking to show me that my backlight pin is slightly misbehaving...
but still no real output on the shield as in: no words at all... working on it
Cannot get it to work.
Since I rechecked all and tried all the error solutions I found on the net I'm coming to the conclusion that it may be broken.
Will get my hands on a uno the next days and will test it with that to check if it really was my wiring or if simply is broken.
Can this be?
Ah and I tried to regulate the back lighting with the screw thingy(not sure of the English name) but the backlight doesn't change at all
feendrache:
Cannot get it to work.
Since I rechecked all and tried all the error solutions I found on the net I'm coming to the conclusion that it may be broken.
Will get my hands on a UNO the next days and will test it with that to check if it really was my wiring or if simply is broken.
Well it might work better plugged on to a UNO for which it is designed if you are unable to emulate the corresponding pin connections with a Nano.
feendrache:
Ah and I tried to regulate the back lighting with the screw thingy(not sure of the English name) but the backlight doesn't change at all
Paul__B:
Well it might work better plugged on to a UNO for which it is designed if you are unable to emulate the corresponding pin connections with a Nano.
I think i was able to emulate the corresponding pins... i rechecked all of them a couple of times... but i will try it with the UNO anyway
Paul__B:
Nor would you ever expect it to.
yeah figured that out after i wrote it... was kind of tired i think
It should work with the Nano. You need to make sure that you are hooking up the proper pins from the nano to the shield.
You can use any pins you want on the nano; however, the shield requires using certain pins.
If you use different arduino digital pins than what the shield would be using on an Uno then you must wire up the pins you use based on functionality.
Not sure which shield you have but most of the lcd keypads use these shield pins:
To avoid confusion it is simplest to use the same arduino digital pins on the Nano, but if you don't want to then simply wire up the desired pins as needed to the appropriate shield pin for the desired lcd pin function.
i.e. if you wanted digital pin 12 to be RS then you would wire up nano digital pin 12 to shield digital pin 8 (the RS pin).
and digital pin 11 to be EN then you would wire up nano digital pin 11 to shield digital pin 9 (the EN pin)
etc...
My recommendation would be use the same digital pin numbers on nano as the ones that would be used when plugged into an uno; that way the same sketch will work on a nano or an uno.
Also if you wire it up that way, you can run the hd44780 library diagnostic tool (LCDKeypadCheck) that will check for a backlight circuit issue as well as all the examples included in the hd44780_pinIO i/o class.
And if your shield does have the backlight circuit issue and you want to safely use the backlight, you can use the hd44780 library instead of the LiquidCrystal library as it will work around the backlight issue in s/w to protect the Arduino processor.
I connected the shield as you suggested, only thing i didn't try so far was using the other library... used only the LiquidCrystal.
I did the backlight check mentioned in the other thread and got a rapid blinking of the backlighting but through all of this i never got a single sign or symbol on the display... it fires only the backlighting not bringing up ANY of the test words or symbols.
I connected the shield as you suggested, only thing i didn't try so far was using the other library... used only the LiquidCrystal.
So are you saying it is all working now?
I did the backlight check mentioned in the other thread and got a rapid blinking of the backlighting but through all of this i never got a single sign or symbol on the display... it fires only the backlighting not bringing up ANY of the test words or symbols.
What thread? What backlight check?
If you are talking about my lcd keypad check sketch, then if things are hooked up correctly it will display the test results on the LCD display.
The latest version is included in the hd44780 library in the hd44780_pinIO i/o class.
The test sketch expects that the arduino pins used are those shown in post #5
I'll have to wait till tomorrow till i'll be able to check it with the other library.
And it's not working as far as no writing appears at the display... the backlight check (wich is supposed to test the backlight issue with possibly harming the arduino connected to the display) script ended in the rapid blinking of the display but still no Text at all...
will write tomorrow as soon as i was able to test it
Edit:
Paul__B:
Oh, and you should have read this thread at the top of the forum listing relating to the "Keypad shield".
feendrache:
And it's not working as far as no writing appears at the display... the backlight check (wich is supposed to test the backlight issue with possibly harming the arduino connected to the display) script ended in the rapid blinking of the display but still no Text at all...
Again, What backlight check? Is it my test sketch? (as far as I know nobody else has written one) or something else?
It is very rare for these simple LCDs to have issues, unless they were fried from hooking things up incorrectly. Even then they are pretty tough and can take quite a bit of abuse. power & gnd being the exceptions.
The potentiometer does not control or affect the backlight. It controls the contrast of the pixels on the display.
If the LCD control and data signals are not wired properly, you won't see the desired output. However you should see a line of blocks on the display as that is the default power state for the LCD.
If you are not seeing any pixels at all on the display, including the blocks, then it is likely that the contrast is not adjusted properly.
At one end of adjustment all the pixels will always be on, at the other end, all the pixels will always be off. Somewhere in the middle is where you see only the proper pixels.
Post a description of how you have wired the shield to your nano.
I.e. which Arduino pin goes to which shield pin.
Post a photo of your device and wiring so we can look at it.
Some shields use a multi turn pot which can take many turns of adjustment.
Yes, it is indeed, a ten turn pot. And the correct point is very close to one end (the ground end).
I note it is mounted near the edge of the PCB. If you can identify which end terminal of the potentiometer connects to Vcc - 5 V - and that there is only one PCB trace going to it, you could cut that trace to make it twice as easy to adjust, And if you can then connect both ends of the pot together (which is to say, both to ground), it would make it twice as easy again to adjust!
This silly mistake in the design (in fact, in most designs using these LCDs) is a major source of complaints here!
Be careful with backlight control. If you use the hd44780 library you can safely use backlight() and noBacklight() to control it.
If you don't want/need to control the backlight save an arduino pin and don't connect one to the D10 pin and the backlight should always be on.
@Paul___B
thank you for your hints... but i think i'm totally happy with it working and will not meddle with it... when i worked with this stuff a bit more maybe, but for now it is working and that is ok
@bperrybap
yeah using the hd44780 but i think i will just disconnect the D10 pin since the backlight always on is ok for my project right now.
From a physical size and arduino pin perspective, you may want to consider not using the LCD shield with the nano.
A $1 USD i2c backpack would reduce the LCD pin count to 2 instead of 6 and you could use a small piece of PCB strip board for the buttons and the resistor ladder network.
Or you could even wire the buttons directly to the nano and use 5 digital pins instead of using an analog pin and the resistor ladder network. (if using the i2c backpack 4 pins would be freed up so it would only cost a net of 1 pin)
Just something to keep in mind as you move forward.
Also, not sure if you want / need faster or lower overhead for controlling the LCD but keep in mind that the hd44780 library is quite a bit faster than the bundled LiquidCrystal library.
You can run the included LCDiSpeed sketch to compare the speed of the hd44780_pinIO i/o class vs the LiquidCrystal library.
While I have just purchased another one (or two if no-one out-bids me) of these shields "just for the heck of it" as a result of this discussion and to see how practical it is to modify the potentiometer connections, I do not see this shield as being particularly useful overall. More of a beginner's toy to go with an Arduino UNO which is in itself not a particularly practical form factor.
Alternatively I could have gone searching through my stack of 52l bins to find where I put the LCD shields I already have from some years back.
yeah i bought it mainly to have something to start with and since i'm a programmer for some time i fairly new to this and i wanted to have a lcd AND some input buttons to use for testing how i could work with input stuff.
This was a really good looking package for this.
I will use it to test some of my ideas and if these ideas really get into a full-blown "object" to use i think i will use a small lcd combined with custom buttons and not these. But i think for testing and learning it'S quite cool.
