SD MMC
About
Note
This is a work in progress project and this section is still missing. If you want to contribute, please see the Contributions Guide.
Example
To get started with SD_MMC, you can try:
SDMMC Test
/*
* pin 1 - D2 | Micro SD card |
* pin 2 - D3 | /
* pin 3 - CMD | |__
* pin 4 - VDD (3.3V) | |
* pin 5 - CLK | 8 7 6 5 4 3 2 1 /
* pin 6 - VSS (GND) | ▄ ▄ ▄ ▄ ▄ ▄ ▄ ▄ /
* pin 7 - D0 | ▀ ▀ █ ▀ █ ▀ ▀ ▀ |
* pin 8 - D1 |_________________|
* ║ ║ ║ ║ ║ ║ ║ ║
* ╔═══════╝ ║ ║ ║ ║ ║ ║ ╚═════════╗
* ║ ║ ║ ║ ║ ║ ╚══════╗ ║
* ║ ╔═════╝ ║ ║ ║ ╚═════╗ ║ ║
* Connections for ║ ║ ╔═══╩═║═║═══╗ ║ ║ ║
* full-sized ║ ║ ║ ╔═╝ ║ ║ ║ ║ ║
* SD card ║ ║ ║ ║ ║ ║ ║ ║ ║
* ESP32-S3 DevKit | 21 47 GND 39 3V3 GND 40 41 42 |
* ESP32-S3-USB-OTG | 38 37 GND 36 3V3 GND 35 34 33 |
* ESP32 | 4 2 GND 14 3V3 GND 15 13 12 |
* Pin name | D1 D0 VSS CLK VDD VSS CMD D3 D2 |
* SD pin number | 8 7 6 5 4 3 2 1 9 /
* | █/
* |__▍___▊___█___█___█___█___█___█___/
* WARNING: ALL data pins must be pulled up to 3.3V with an external 10k Ohm resistor!
* Note to ESP32 pin 2 (D0): Add a 1K Ohm pull-up resistor to 3.3V after flashing
*
* SD Card | ESP32
* D2 12
* D3 13
* CMD 15
* VSS GND
* VDD 3.3V
* CLK 14
* VSS GND
* D0 2 (add 1K pull up after flashing)
* D1 4
*
* For more info see file README.md in this library or on URL:
* https://github.com/espressif/arduino-esp32/tree/master/libraries/SD_MMC
*/
#include "FS.h"
#include "SD_MMC.h"
// Default pins for ESP-S3
// Warning: ESP32-S3-WROOM-2 is using most of the default GPIOs (33-37) to interface with on-board OPI flash.
// If the SD_MMC is initialized with default pins it will result in rebooting loop - please
// reassign the pins elsewhere using the mentioned command `setPins`.
// Note: ESP32-S3-WROOM-1 does not have GPIO 33 and 34 broken out.
// Note: if it's ok to use default pins, you do not need to call the setPins
int clk = 36;
int cmd = 35;
int d0 = 37;
int d1 = 38;
int d2 = 33;
int d3 = 39; // GPIO 34 is not broken-out on ESP32-S3-DevKitC-1 v1.1
void listDir(fs::FS &fs, const char *dirname, uint8_t levels) {
Serial.printf("Listing directory: %s\n", dirname);
File root = fs.open(dirname);
if (!root) {
Serial.println("Failed to open directory");
return;
}
if (!root.isDirectory()) {
Serial.println("Not a directory");
return;
}
File file = root.openNextFile();
while (file) {
if (file.isDirectory()) {
Serial.print(" DIR : ");
Serial.println(file.name());
if (levels) {
listDir(fs, file.path(), levels - 1);
}
} else {
Serial.print(" FILE: ");
Serial.print(file.name());
Serial.print(" SIZE: ");
Serial.println(file.size());
}
file = root.openNextFile();
}
}
void createDir(fs::FS &fs, const char *path) {
Serial.printf("Creating Dir: %s\n", path);
if (fs.mkdir(path)) {
Serial.println("Dir created");
} else {
Serial.println("mkdir failed");
}
}
void removeDir(fs::FS &fs, const char *path) {
Serial.printf("Removing Dir: %s\n", path);
if (fs.rmdir(path)) {
Serial.println("Dir removed");
} else {
Serial.println("rmdir failed");
}
}
void readFile(fs::FS &fs, const char *path) {
Serial.printf("Reading file: %s\n", path);
File file = fs.open(path);
if (!file) {
Serial.println("Failed to open file for reading");
return;
}
Serial.print("Read from file: ");
while (file.available()) {
Serial.write(file.read());
}
}
void writeFile(fs::FS &fs, const char *path, const char *message) {
Serial.printf("Writing file: %s\n", path);
File file = fs.open(path, FILE_WRITE);
if (!file) {
Serial.println("Failed to open file for writing");
return;
}
if (file.print(message)) {
Serial.println("File written");
} else {
Serial.println("Write failed");
}
}
void appendFile(fs::FS &fs, const char *path, const char *message) {
Serial.printf("Appending to file: %s\n", path);
File file = fs.open(path, FILE_APPEND);
if (!file) {
Serial.println("Failed to open file for appending");
return;
}
if (file.print(message)) {
Serial.println("Message appended");
} else {
Serial.println("Append failed");
}
}
void renameFile(fs::FS &fs, const char *path1, const char *path2) {
Serial.printf("Renaming file %s to %s\n", path1, path2);
if (fs.rename(path1, path2)) {
Serial.println("File renamed");
} else {
Serial.println("Rename failed");
}
}
void deleteFile(fs::FS &fs, const char *path) {
Serial.printf("Deleting file: %s\n", path);
if (fs.remove(path)) {
Serial.println("File deleted");
} else {
Serial.println("Delete failed");
}
}
void testFileIO(fs::FS &fs, const char *path) {
File file = fs.open(path);
static uint8_t buf[512];
size_t len = 0;
uint32_t start = millis();
uint32_t end = start;
if (file) {
len = file.size();
size_t flen = len;
start = millis();
while (len) {
size_t toRead = len;
if (toRead > 512) {
toRead = 512;
}
file.read(buf, toRead);
len -= toRead;
}
end = millis() - start;
Serial.printf("%u bytes read for %lu ms\n", flen, end);
file.close();
} else {
Serial.println("Failed to open file for reading");
}
file = fs.open(path, FILE_WRITE);
if (!file) {
Serial.println("Failed to open file for writing");
return;
}
size_t i;
start = millis();
for (i = 0; i < 2048; i++) {
file.write(buf, 512);
}
end = millis() - start;
Serial.printf("%u bytes written for %lu ms\n", 2048 * 512, end);
file.close();
}
void setup() {
Serial.begin(115200);
/*
// If you want to change the pin assignment on ESP32-S3 uncomment this block and the appropriate
// line depending if you want to use 1-bit or 4-bit line.
// Please note that ESP32 does not allow pin change and will always fail.
//if(! setPins(clk, cmd, d0)){
//if(! setPins(clk, cmd, d0, d1, d2, d3)){
Serial.println("Pin change failed!");
return;
}
*/
if (!SD_MMC.begin()) {
Serial.println("Card Mount Failed");
return;
}
uint8_t cardType = SD_MMC.cardType();
if (cardType == CARD_NONE) {
Serial.println("No SD_MMC card attached");
return;
}
Serial.print("SD_MMC Card Type: ");
if (cardType == CARD_MMC) {
Serial.println("MMC");
} else if (cardType == CARD_SD) {
Serial.println("SDSC");
} else if (cardType == CARD_SDHC) {
Serial.println("SDHC");
} else {
Serial.println("UNKNOWN");
}
uint64_t cardSize = SD_MMC.cardSize() / (1024 * 1024);
Serial.printf("SD_MMC Card Size: %lluMB\n", cardSize);
listDir(SD_MMC, "/", 0);
createDir(SD_MMC, "/mydir");
listDir(SD_MMC, "/", 0);
removeDir(SD_MMC, "/mydir");
listDir(SD_MMC, "/", 2);
writeFile(SD_MMC, "/hello.txt", "Hello ");
appendFile(SD_MMC, "/hello.txt", "World!\n");
readFile(SD_MMC, "/hello.txt");
deleteFile(SD_MMC, "/foo.txt");
renameFile(SD_MMC, "/hello.txt", "/foo.txt");
readFile(SD_MMC, "/foo.txt");
testFileIO(SD_MMC, "/test.txt");
Serial.printf("Total space: %lluMB\n", SD_MMC.totalBytes() / (1024 * 1024));
Serial.printf("Used space: %lluMB\n", SD_MMC.usedBytes() / (1024 * 1024));
}
void loop() {
}
Complete list of SD MMC examples.