Using the SD Card on The Extended Core (CWV)

Instead of listing a complete example here, you will find the code change to the existing SD Card Example in Arduino already. This way when the SD Card Example is updated, this example will not be outdated. It also very specific show what is different from the existing example.

The Arduino Example

• Use a micro SD Card with 32Gb or less of capacity and insert into the CWV SD Card holder.
• Open the Example: File 👉 Examples 👉 SD (Under Examples for ESP32...) 👉 SD_Test
• Find this line if (!SD.begin()) {
• And overwrite that line with this:

  delay(1000);
  Serial.println();
  Serial.println("Initializing SD card...");

  SPIClass spi = SPIClass(HSPI);
  spi.begin(14 /* SCK */, 12 /* MISO */, 13 /* MOSI */, 5 /* CS */);
  if (!SD.begin(5, spi)) { 

Notes

• I always add a 1 second delay so I don't miss anything in the Serial printout
• I always print an empty line, so my next line starts from a fresh line and not after the noise from the startup
• The CVW uses the HSPI (not the default VSPI). The standard pins on the HSPI is a per the code.
• The SD Card sits on GPIO5 as Chip Select (CS)

Before

After

Library Use

This repository contains a library with allow a Python program to interact with the SD Card in the xChip, while the xChip is connected to your computer over USB. The Python program SDworks.py (which you find in this repository), has 3 commands:

LISTDIR

This list all the files in the root folder of the SD Card

DELETEALL

This deletes all the files (not folders) in the root folder

TRANSFER

This transfers a file, such as data0000.json to your computer, but also makes a Comma Separated Values file (.csv) and an Excel file (.xlsx)

Installation

You obvisouly need Python. And then some packages you can install with

$ pip install -r requirements.txt