How to compile a firmware for ESP32 that can handle SD Cards

[MaBecker]

/* jshint esversion: 6 */
//File_IO_and_SD_cards.js 

if ( process.env.BOARD == "ESP32") {

    M5Stack = require("M5STACKS");
    SPI1.setup({mosi:M5Stack.MOSI, miso:M5Stack.MISO, sck:M5Stack.SCK});
    E.connectSDCard(SPI1, M5Stack.CS);

    // see what's on the device
    //console.log(require("fs").readdirSync());
}


if ( process.env.BOARD == "PICO_R1_3") {

  // Wire up up MOSI, MISO, SCK and CS pins (along with 3.3v and GND)
  SPI1.setup({mosi:B5, miso:B4, sck:B3});
  E.connectSDCard(SPI1, B6 /*CS*/);
 
  // see what's on the device
  //console.log(require("fs").readdirSync());

}

No error on Pico, but this one on ESP32.

Uncaught Error: Unimplemented on Linux
 at line 5 col 37
    E.connectSDCard(SPI1, M5Stack.CS);

Are there some modules or -DSettings for ESP32 missing?

Espruino/libs/filesystem/jswrap_file.c

Lines 145 to 162 in e568c6c

	void jswrap_E_connectSDCard(JsVar *spi, Pin csPin) {
	#ifdef SD_CARD_ANYWHERE
	if (!jsvIsObject(spi)) {
	jsExceptionHere(JSET_ERROR, "First argument is a %t, not an SPI object\n", spi);
	return;
	}
	if (!jshIsPinValid(csPin)) {
	jsExceptionHere(JSET_ERROR, "Second argument is not a valid pin");
	return;
	}
	jswrap_E_unmountSD();
	sdSPISetup(spi, csPin);
	#else
	NOT_USED(spi);
	NOT_USED(csPin);
	jsExceptionHere(JSET_ERROR, "Unimplemented on Linux");
	#endif
	}

[MaBecker]

Wow the solution was there in the same file just a few lines above :)

Espruino/libs/filesystem/jswrap_file.c

Lines 22 to 24 in e568c6c

	#if !defined(LINUX) && !defined(USE_FILESYSTEM_SDIO) && !defined(USE_FLASHFS)
	#define SD_CARD_ANYWHERE
	#endif

So the solution is to remove this line

Espruino/boards/ESP32.py

Line 35 in e568c6c

'FLASHFS',

and build a new firmware version and it works.

[AkosLukacs]

Just a hunch: does writing to internal flash still work?

[gfwilliams]

Using Storage it would - FLASHFS is something different (FAT32 on the internal flash)

[AkosLukacs]

That's great news, thanks for the clarification.
Btw, is there a list of boards.py or common compiler flags?