SPIFFS file read and write example
Posted: Mon Feb 15, 2016 6:03 pmToday I coded a basic sketch getting to learn to use the SPIFFS filesystem.
The sketch is attached here, maybe it's of use to anyone.
The sketch is attached here, maybe it's of use to anyone.
Code: Select all
// Very basic Spiffs example, writing 10 strings to SPIFFS filesystem, and then read them back
// For SPIFFS doc see : https://github.com/esp8266/Arduino/blob/master/doc/filesystem.md
// Compiled in Arduino 1.6.7. Runs OK on Wemos D1 ESP8266 board.
#include "FS.h"
void setup() {
Serial.begin(9600);
Serial.println("\nVery basic Spiffs example, writing 10 lines to SPIFFS filesystem, and then read them back");
SPIFFS.begin();
// Next lines have to be done ONLY ONCE!!!!!When SPIFFS is formatted ONCE you can comment these lines out!!
Serial.println("Please wait 30 secs for SPIFFS to be formatted");
SPIFFS.format();
Serial.println("Spiffs formatted");
}
void loop() {
// open file for writing
File f = SPIFFS.open("/f.txt", "w");
if (!f) {
Serial.println("file open failed");
}
Serial.println("====== Writing to SPIFFS file =========");
// write 10 strings to file
for (int i=1; i<=10; i++){
f.print("Millis() : ");
f.println(millis());
Serial.println(millis());
}
f.close();
// open file for reading
f = SPIFFS.open("/f.txt", "r");
if (!f) {
Serial.println("file open failed");
} Serial.println("====== Reading from SPIFFS file =======");
// write 10 strings to file
for (int i=1; i<=10; i++){
String s=f.readStringUntil('\n');
Serial.print(i);
Serial.print(":");
Serial.println(s);
}
// wait a few seconds before doing it all over again
delay(3000);
}