Ili9341 problems

Using Arduino Displays
#1

I’ve been putting together a project using a Nano and an Ili9341 LCD (tried a couple). All pins correctly defined, triple checked, every pin except miso connected. I’ve done a fair amount of searching.

Using the Adafruit_ili9341 library right from github, and trying to run a graphictest I get nothing back.

I checked the constructor is complete, all pins passed Inc reset.

Using 3v3 logic.

I checked voltage to the LCD, found the unit I was using was passing 2.95v, not 3.3, and the on board ldo reg was passing it through, but I bypassed it anyway with a wire mod to be sure.

Still a white screen. Zero visible interaction.

I scoped clock and data, attached.

Really starting to run low on ways of debugging.
I don’t have the code with me just now, but I will upload it later, however the default graphictest ino doesn’t function.

image003.jpg
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#2

Attempted to hold RST and CS high via external pull-up, no success.

Code sample:

#include <SoftwareSerial.h>
SoftwareSerial dcc(A3,A4); // RX TX

#include “Adafruit_GFX.h” // Core graphics library
#include “Adafruit_ILI9341.h” // Hardware-specific library
#include “SPI.h”

// hardware SPI pins for Nano
#define _sck 13
#define _mosi 11
#define _cs 10
#define _dc_rs 9
#define _reset 7

Adafruit_ILI9341 tft = Adafruit_ILI9341(_cs, _dc_rs, _mosi, _sck, _reset, -1);

boolean newData = false;
boolean cv1 = false;
int loco = 0, fd, fl, f1, f2, f3,f4, f5, f6, f7, f8, Speed, function, e_stop, A, Amax;
String inString;
String speedString1;
String speedString2;
String string_alarm1, string_alarm2, string_alarm3;
String option;
int a[30];
int count;
int Atrig;
int cv_set;

void setup() {

dcc.begin(9600);
Serial.begin(9600);
tft.begin();

tft.setRotation(3);
tft.fillScreen(ILI9341_BLUE);
tft.setTextColor(ILI9341_WHITE);

Noticed that while it’s straight on, the screen appears solid white, but viewed at an angle i can see patterned lines (non-descript) flickering down the screen while the code is outputting to it.

#3

Sussed it. I assumed it must be a software issue as all the hardware side checked out.

Re-installing the libraries from the library manager, rather than dropping them into the users>arduino>libraries folder did the trick!

#4