esp-idf-ftpClient

FTP Client for esp-idf.

Software requirements

ESP-IDF V5.0 or later.
ESP-IDF V4.4 release branch reached EOL in July 2024.

Installation

git clone https://github.com/nopnop2002/esp-idf-ftpClient
cd esp-idf-ftpClient/
idf.py menuconfig
idf.py flash

Configuration

File System Selection

This project supports the following file systems.
You can select any one using menuconfig.

• SPIFFS file system on Builtin SPI Flash Menory
• FAT file system on Builtin SPI Flash Menory
• LITTLEFS file system on Builtin SPI Flash Menory
• FAT file system on SPI peripheral SDCARD
• FAT file system on SDMMC peripheral SDCARD(Valid only for ESP32/ESP32S3)
• FAT file system on External SPI Flash Memory like Winbond W25Q64

Note:
The connection when using SDSPI, SDMMC, and External SPI flash Memory will be described later.

Note:
LITTLEFS requires ESP-IDF V5.2 or later.

Partition table

Use partitions_example_spiffs.csv when you select SPIFFS file system on Builtin SPI Flash Menory.
Use partitions_example_fatfs.csv when you select FAT file system on Builtin SPI Flash Menory.
Use partitions_example_littlefs.csv when you select LITTLEFS file system on Builtin SPI Flash Menory.

If you need more storage space in the Builtin SPI Flash Menory, you will need to modify these files.

Wifi Setting

FTP Server Setting

Using FAT file system on SPI peripheral SDCARD

You can change it to any pin using menuconfig.

Note:
This project doesn't utilize card detect (CD) and write protect (WP) signals from SD card slot.

Using FAT file system on SDMMC peripheral SDCARD

On ESP32, SDMMC peripheral is connected to specific GPIO pins using the IO MUX.
GPIO pins cannot be customized.
GPIO2 and GPIO12 cannot be changed.
So using 4-line SD mode with ESP32 is very tricky.
Please see the table below for the pin connections.

• 1line mode
  

• 4line mode
  

On ESP32-S3, SDMMC peripheral is connected to GPIO pins using GPIO matrix.
This allows arbitrary GPIOs to be used to connect an SD card.

• 1line mode
  

• 4line mode
  

Note about GPIO2 (ESP32 only)

GPIO2 pin is used as a bootstrapping pin, and should be low to enter UART download mode. One way to do this is to connect GPIO0 and GPIO2 using a jumper, and then the auto-reset circuit on most development boards will pull GPIO2 low along with GPIO0, when entering download mode.

• Some boards have pulldown and/or LED on GPIO2. LED is usually ok, but pulldown will interfere with D0 signals and must be removed. Check the schematic of your development board for anything connected to GPIO2.

Note about GPIO12 (ESP32 only)

GPIO12 is used as a bootstrapping pin to select output voltage of an internal regulator which powers the flash chip (VDD_SDIO).
This pin has an internal pulldown so if left unconnected it will read low at reset (selecting default 3.3V operation).
When adding a pullup to this pin for SD card operation, consider the following:

• For boards which don't use the internal regulator (VDD_SDIO) to power the flash, GPIO12 can be pulled high.
• For boards which use 1.8V flash chip, GPIO12 needs to be pulled high at reset. This is fully compatible with SD card operation.
• On boards which use the internal regulator and a 3.3V flash chip, GPIO12 must be low at reset. This is incompatible with SD card operation.
  • In most cases, external pullup can be omitted and an internal pullup can be enabled using a gpio_pullup_en(GPIO_NUM_12); call. Most SD cards work fine when an internal pullup on GPIO12 line is enabled. Note that if ESP32 experiences a power-on reset while the SD card is sending data, high level on GPIO12 can be latched into the bootstrapping register, and ESP32 will enter a boot loop until external reset with correct GPIO12 level is applied.
  • Another option is to burn the flash voltage selection efuses. This will permanently select 3.3V output voltage for the internal regulator, and GPIO12 will not be used as a bootstrapping pin. Then it is safe to connect a pullup resistor to GPIO12. This option is suggested for production use.

Using FAT file system on External SPI Flash Memory

I tested these SPI Flash Memory.
https://github.com/nopnop2002/esp-idf-w25q64

Note: You will get an error. It works fine after a few resets. At the moment, it is not stable.

I (2121) FTP: Initializing external SPI Flash
I (2121) FTP: Pin assignments:
I (2121) FTP: MOSI: 23   MISO: 19   SCLK: 18   CS:  5
E (2131) memspi: no response
E (2131) FTP: Failed to initialize external Flash: ESP_ERR_INVALID_RESPONSE (0x108)

After reset

I (1621) FTP: Initializing external SPI Flash
I (1621) FTP: Pin assignments:
I (1631) FTP: MOSI: 23   MISO: 19   SCLK: 18   CS:  5
I (1631) spi_flash: detected chip: winbond
I (1641) spi_flash: flash io: dio
I (1641) FTP: Initialized external Flash, size=8192 KB, ID=0xef4017
I (1651) FTP: Adding external Flash as a partition, label="storage", size=8192 KB
I (1661) FTP: Initializing FAT file system
I (1661) FTP: Mount FAT filesystem on /root

Using ESP32-CAM

The ESP32-CAM development board has a micro SD card slot on the board.
It is connected to the ESP32 by SDMMC with 4-line Mode.
No equipment other than the development board is required.
It works very stably.

Using LilyGo ESP32-S2

The LilyGo ESP32-S2 development board has a micro SD card slot on the board.
It is connected to the ESP32 by SPI, and the peripheral power is supplied from GPIO14.
No equipment other than the development board is required.
It works very stably.

API

Based on ftplib V4.0-1.

Server Connection

• ftpClientConnect() - Connect to a remote server
• ftpClientLogin() - Login to remote machine
• ftpClientQuit() - Disconnect from remote server
• ftpClientSetOptions() - Set Connection Options

Directory Functions

• ftpClientChangeDir() - Change working directory
• ftpClientMakeDir() - Create a directory
• ftpClientRemoveDir() - Remove a directory
• ftpClientDir() - List a remote directory
• ftpClientNlst() - List a remote directory
• ftpClientChangeDirUp() - Change to parent directory
• ftpClientPwd() - Determine current working directory

File to File Transfer

• ftpClientGet() - Retreive a remote file
• ftpClientPut() - Send a local file to remote
• ftpClientDelete() - Delete a remote file
• ftpClientRename() - Rename a remote file

File to Program Transfer

These routines allow programs access to the data streams connected to remote files and directories.

• ftpClientAccess() - Open a remote file or directory
• ftpClientRead() - Read from remote file or directory
• ftpClientWrite() - Write to remote file
• ftpClientClose() - Close data connection

Using long file name support

By default, FATFS file names can be up to 8 characters long.
If you use filenames longer than 8 characters, you need to change the values below.

Screen Shot

• Get remote file list
• Write local file
• Put file to server
• Remove local file
• Get file from sever
• Read local file

Truble shooting

By changing this, you can see the response from the server:

#define FTP_CLIENT_DEBUG                    2

FTP Server using python

https://github.com/nopnop2002/esp-idf-ftpClient/tree/master/python-ftp-server

Reference

• FTP Server using FAT File system.
  Since it uses the FAT file system instead of SPIFFS, directory operations are possible.
  https://github.com/nopnop2002/esp-idf-ftpServer

• File copy using scp.
  https://github.com/nopnop2002/esp-idf-scp-client

• File copy using smb.
  https://github.com/nopnop2002/esp-idf-smb-client