esp-idf-24c

Two-Wire Serial EEPROM Driver for esp-idf.

Software requirements

ESP-IDF V4.4/V5.x.
ESP-IDF V5.0 is required when using ESP32-C2.
ESP-IDF V5.1 is required when using ESP32-C6.

Note for ESP-IDF V5.2.
A new i2c driver is now available in ESP-IDF V5.2.
Under ESP-IDF V5.2 or later, this project uses a new i2c driver.

Installation

git clone https://github.com/nopnop2002/esp-idf-24c
cd esp-idf-24c
idf.py set-target {esp32/esp32s2/esp32s3/esp32c2/esp32c3/esp32c6}
idf.py menuconfig
idf.py flash

Configuration

You have to set this config value with menuconfig.

• CONFIG_MODEL
• CONFIG_SCL_GPIO
• CONFIG_SDA_GPIO
• CONFIG_I2C_ADDRESS

Memory size

Device	Number of Bits	Address range	i2c address
24C02	2K	0x00-0xFF	0x50-0x57
24C04	4K	0x00-0x1FF	0x50/0x52/0x54/0x56(*1)
24C08	8K	0x00-0x3FF	0x50/0x54(*2)
24C16	16K	0x00-0x7FF	0x50(*3)
24C32	32K	0x00-0xFFF	0x50-0x57
24C64	64K	0x00-0x1FFF	0x50-0x57
24C128	128K	0x00-0x3FFF	0x50-0x53
24C256	256K	0x00-0x7FFF	0x50-0x53
24C512	512K	0x00-0xFFFF	0x50-0x53

(*1) Two consecutive i2c entries are used in the library.
(*2) Four consecutive i2c entries are used in the library.
(*3) Eight consecutive i2c entries are used in the library.

API

// Open device
//   i2c_port:I2C_NUM_0/I2C_NUM_1
esp_err_t InitRom(EEPROM_t * dev, i2c_port_t i2c_port);

// Get EEPROM maximum address
uint16_t MaxAddress(EEPROM_t * dev);

// Read data from EEPROM
//   data_addr:read address
//   data:read data buffer
esp_err_t ReadRom(EEPROM_t * dev, uint16_t data_addr, uint8_t * data);

// Write data to EEPROM
//   data_addr:write address
//   data:write data buffer
esp_err_t WriteRom(EEPROM_t * dev, uint16_t data_addr, uint8_t data);

Wireing

24Cxx		ESP32	ESP32-S2/S3	ESP32-C2/C3/C6
A0	--	GND	GND	GND	(*1)
A1	--	GND	GND	GND	(*1)
A2	--	GND	GND	GND	(*1)
GND	--	GND	GND	GND
SDA	--	GPIO21	GPIO11	GPIO4	(*2)
SCL	--	GPIO22	GPIO12	GPIO5	(*2)
WP	--	GND	GND	GND
VCC	--	3.3V	3.3V	3.3V

(*1) I2C Address selection. See data sheet.
(*2) You can change any GPIO using menuconfig.

Typical circuit.
When A0 A1 A2 is GND, i2c address is 0x50.

Serial Console

• 24C04
  

• 24C16
  

• 24C32
  

• 24C64
  

• 24C128
  

• 24C256
  

• 24C512