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Character LCDs / Re: NHD-0220FZ-FSW-GBW-P-33V3
« Last post by Alee_S on January 04, 2019, 10:27:04 AM »
Hi timbro,

As far as connecting DB0-DB3, you can connect them to ground or leave them disconnected, as either option should work for 4-bit parallel interface.

Please see the sample code provided below as a reference, which I have tested and verified to work. The code provided is written for an Arduino Uno. 

Code: [Select]
/******** INITIAL DEFINITIONS***************/

#define E_Pin 10
#define R_W    9
#define R_S    8

/************************ CHAR STRING**********/

char const text1[] = ("NEWHAVEN DISPLAY");
char const text2[] = ("2x20 LCD DISPLAY");

/************ Functions************/
void latch(){                           // command to latch E
  digitalWrite(E_Pin, HIGH);            // Latch
  digitalWrite(E_Pin, LOW);
void command(char i){
  PORTD = i;
  digitalWrite(R_S, LOW);               // Command
  digitalWrite(R_W, LOW);               // Write
  latch();                              // take upper 4 bits
  i = i<<4;                             // shift 4 bits
  PORTD = i;                            // Take lower 4 bits
void data(char i){
  PORTD = i;
  digitalWrite(R_S, HIGH);              // Data
  digitalWrite(R_W, LOW);               // Write
  latch();                              // take upper 4 bits
  i = i<<4;                             // shift 4 bits
  PORTD = i;                            // Take lower 4 bits

/***********INITIALIZE DISPLAY************************/

void init1(){
digitalWrite(E_Pin, LOW);                                                     
 delay(100);                            //Wait >15 msec after power is applied
 PORTD=0x30  ;                         // Put 30 on port D           
 delay(30);                             //must wait 5ms, busy flag not available
 latch();                              //command 0x30 = Wake up
 delay(10);                             //must wait 160us, busy flag not available
 latch();                              //command 0x30 = Wake up #2
 delay(10);                             //must wait 160us, busy flag not available
 latch();                              //command 0x30 = Wake up #3
 delay(10);                             //can check busy flag now instead of delay 
 PORTD = 0x20;                          //put 0x20 on the output port (NEEDED TO SET 4-bit INTERFACE)         
 command(0x28);                         //Function set: 4-bit/2-line 
 command(0x0F);                         //Display ON; Blinking cursor
 command(0x06);                         //Entry Mode sets

void clear_screen(){                    // clear display
void ret_home(){                        // Return to home position
void disp(){                            // DISPLAY TEXT
  ret_home();                                 // Brings back to First Line
  for( int i = 0; i<16; i++){
  command(0xC0);                              // Second Line
  for (int i = 0; i<16; i++){

void setup() {
  DDRD = 0xFF; // First 8 pins of PORT D as output
  DDRB = 0x07; // Port B first 3 pins as output

void loop() {

If the issue persists, can you provide/upload the following:
-Image of your hardware connections?
-Measured voltages across Pin 3 (contrast pin) at both limits of the POT? 
-The P/N of the other displays you can drive with your code?

OLEDs / Best newhaven display?
« Last post by chahath on January 04, 2019, 08:55:00 AM »
So I have several Arduino Uno's and I'm finally going to purchase a display to increase my project abilities. I'm definitely going to buy a newhaven display, but I'm not sure which one to get. I understand there are tons of different options and sizes but I was wondering if anyone recommends a basic all around good display to use. I'm not exactly sure what kind of project I want to take on with the display at this point. I don't think it matters if it has color or not. The only thing is that it should be $40 or less.

TFTs / Re: NHD-7.0-HDMI-N-RSXN-RTU Ghost images
« Last post by Ted_M on January 03, 2019, 10:25:11 AM »
Please check the power supply used to drive this display.  Try using a 6V supply that can support 1.5 to 2 amps to see if this resolves the issue.

Best Regards,

TFTs / NHD-7.0-HDMI-N-RSXN-RTU Ghost images
« Last post by Azabel86 on January 03, 2019, 08:50:39 AM »
Hi i have a NHD-7.0-HDMI-N-RSXN-RTU connected to a raspberry pi 3.
When i change apps the new app appears right but the old its still seen and slowly fade about one - two seconds until the new app is correctly seen.
Other displays work well.

I dont think this is normal behavior.
Character LCDs / NHD-0220FZ-FSW-GBW-P-33V3
« Last post by timbro on January 03, 2019, 06:31:11 AM »
Hello all...
We are trying to operate this display (NHD-0220FZ-FSW-GBW-P-33V3) with 4 bits and have achieved absolutely nothing so far.
Now we are questioning if we have understood the data sheet and have all the correct connections we need.
First we tried connecting everything with DB0-DB3 grounded. Then we tried DB0-DB3 not connected. Now we have tried connecting to a header on the 12 pin side only. Still nothing.
All the voltages are there.
Interestingly, we have a 10k pot on the contrast and cannot get any change in the display from one end of the pot to the other. I figured this is strange because I would have thought this was a quite separate to actually configuring the display for operation.
Finally, thinking we may have copped a faulty display, we tried another and it is exactly the same - completely unresponsive. We have another 8 more but I suspect they will all be the same.
We can drive several other displays with our code, so I don't think we are too far out with what we are doing code wise.
Has anyone got some configuration code that we make some comparisons with? or are there an secrets with this display that we should know about.
Thanks in advance...
Cheers, T
TFTs / TFT Display with Beagle Green
« Last post by imsaditya on January 02, 2019, 06:32:49 AM »
We are using Beagle Bone green board. Using default(pre built Linux image) linux image on beagle bone green board. Linux Kernel booting on the board.
When i have connected NHD display "NHD-5.0-800480TF-ATXL#-CTP" and power On the board, board does not  boots  as the board LEDS are not blinking
And  no display on the NHD display.

The connection details between NHD display and beagle green board is attached:

Could you kindly suggest if i need to check any configuration or configuration change that enable LCD display on beagle green board
TFTs / Re: NHD-5.0-HDMI-N-RTXL-CTU Digital Dimming Control
« Last post by georgek on January 01, 2019, 04:52:03 PM »
It is not a solution, it is just a test that proves that our one-wire commands are correct. Removing D8 from the Display board eliminates the ACTIVE signal. This affects negatively the behavior of the display when it is powered on.
Character LCDs / Re: Mounting Question for .050" pitch LCD connector
« Last post by Alee_S on December 31, 2018, 01:57:28 PM »
Hi jimr,

I would recommend taking a look at Samtecs website (, as they have an assortment of connectors and cables at various pitch and length that may help fulfill your requirements.

Graphic LCDs / Re: Newhaven Display Issues
« Last post by Alee_S on December 31, 2018, 01:45:16 PM »
Hi sherloc987!

A pot is a variable resistor that can be adjusted anywhere from 0 ohms to the maximum resistance it is rated to handle. So when the datasheet recommends a 10k~20k pot, it means any pot that has a maximum resistance within a 10k~20k range. 

However, the technique you used of connecting a series of resistors together can also yield proper contrast on the display, pending that you attain a recommended rated voltage of 0.5V across Vo (Pin 3), as shown by the electrical characteristics table on pg. 4 of the Datasheet.

Since you were using resistor values of 10k and above, chances are your contrast voltage on Pin 3 was too high. I would recommend you try to decrement your value of resistors connected to ground (9k, 8k, 7k, etc.) until Vo approaches 0.5 V, and if everything else is working correctly, you should start to see text appear on the display.

Hope this helps!

Please let me know if you need any further assitance!
TFTs / Re: NHD-5.0-HDMI-N-RTXL-CTU Digital Dimming Control
« Last post by Alee_S on December 31, 2018, 01:27:06 PM »
Hi georgek,

I'm glad you got it running! Thanks for posting your solution here as well!  :)
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