Problem writing to SD card on Adafruit 1.44 Color TFT with Wemos Lolin ESP 32

Other Hardware Storage
1

I have a problem getting the SD card slot in the Adafruit 1.44 Color TFT to work with the Wemos Lolin ESP 32. I have tried many tutorials but am unable to get the Wemos to write a txt file on the SD card. In the current setup, the screen works fine but does not work with the SD card. I have attached the code I used below as well as my pin-to-pin connections.

Pin-to-Pin Connections
Adafruit 1.44 Color TFT -> Wemos Lolin ESP32
Vin -> 3V3
Gnd -> Gnd
SCK -> SCK/18
SO -> MISO/19
SI -> MOSI/23
TCS -> 17
RST -> 16
D/C -> 4
CCS -> SS/5/LED

#include <Adafruit_GFX.h>    // Core graphics library
#include <Adafruit_ST7735.h> // Hardware-specific library
#include <SPI.h>
#include <SD.h>

// TFT display and SD card will share the hardware SPI interface.
// Hardware SPI pins are specific to the Arduino board type and
// cannot be remapped to alternate pins.  For Arduino Uno,
// Duemilanove, etc., pin 11 = MOSI, pin 12 = MISO, pin 13 = SCK.
#define TFT_CS  17  // Chip select line for TFT display
#define TFT_RST  16  // Reset line for TFT (or see below...)
#define TFT_DC   4 // Data/command line for TFT
#define SD_CS    5  // Chip select line for SD card

//Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);
File logfile;

char filename[] = "test.txt";

void setup(void) {
  Serial.begin(9600);
  digitalWrite(5, LOW);
  
 
  // Init tft
  tft.initR(INITR_144GREENTAB);
 
  Serial.print("Initializing SD card...");
 
  if (!SD.begin(SD_CS)) {
    Serial.println("failed!");
    return;
  }
  Serial.println("OK!");
}

void loop() {
 
  // only open a new file if it doesn't exist
  if (!SD.exists(filename)) {
    Serial.print("file doesnt exist. Trying to create... ");
    logfile = SD.open(filename, FILE_WRITE);
   
    if (!SD.exists(filename)) {
      Serial.println("couldnt create file");
      return;
    }
   
    logfile.println("A");
    logfile.println("B");
   
    logfile.close();
    Serial.println("file created");
  } else Serial.println("file existed");
 
  Serial.print("Logging to: ");
  Serial.println(filename);
 
  logfile = SD.open(filename, FILE_WRITE);
  if (logfile) {
    logfile.println("A");
    logfile.println("B");
    logfile.close();
  } else Serial.println("file still not exists");
 
  logfile = SD.open(filename);
  if (logfile) {
    Serial.println("test.txt:");
   
    // read from the file until there's nothing else in it:
    while (logfile.available()) {
      Serial.write(logfile.read());
    }
    // close the file:
    logfile.close();
  } else {
    // if the file didn't open, print an error:
    Serial.println("error opening test.txt");
  }
 
  delay(2000);
  Serial.println("###############################");
}

The thing is that when the code is modified for use with the Arduino Uno, the SD writing capabilities seems to work fine. Please help!

2

I'd remove the write pin 5.

3

I took it out, and it did not change anything. Still getting errors, unfortunately.

4

The errors must be a secret?

5

What do you mean?

6

Do you get a failure for the SD card initialization?

Does the file not exist printout occur?

Does the could not create file error occur?

try

void loop()
{
//comment the code you have in your loop() and add the line below.
String toFIle = String(millis());
appendFile(SD, "/data.txt", toFile.c_str() + '\n');
}

//add this to your project


void appendFile(fs::FS &fs, const char * path, const char * message) {
  //log_i("Appending to file: %s\n", path);
  File file = fs.open(path, FILE_APPEND);
  if (!file)
  {
    log_i("Failed to open file for appending");
    return;
  } else {
    file.print(message);
    file.close();
  }
}

Do you get a save to the SD card?

7

I tried out your code, and no file gets created. There have been on error messages in the past or with your code.

8

Sorry I could not help you out. Good luck.

9

Actually, I got it. I just had to import the FS.h library since that seems to be the file system library for ESP32 stuff. Thanks for the help, though!

10

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