ESP8266 Community Forum

how to use DS1307 EEPROM with esp8266
Hi.
sorry for my poor English.
I made a web server to get some big string variables from web and set them to a DS1307 chip so I can use them on my project.
esp8266 uses UART and DS1307 uses I2C. Is it possible to connect them to each other? And how I can access (read & write) DS1307's eeprom with esp?
Thanks in advance.

The DS1307 is not an EEPROM. It is a Real Time Clock - RTC. The ESP8266 does support I2C communications. There are DS1307 libraries that you can use on the ESP8266. The following is just one of them.

https://github.com/Makuna/Rtc

DS1307 RTC is a 5Vcc device. To use it with ESP8266 you need to do voltage translation (level shifting) between 5Vcc and 3.3Vcc.
I think is better to look at a 3.3Vcc device that will work without any problems with your ESP8266.

Some compatible devices, with hardware details, code examples, etc:
- DS3231 Module - General view, simple code example, etc
- DS3231 part 2 - AT24C32 - EEProm data logger usage and examples.
- PCF8563 RTC - General view and code example.
- PCF8563 - ESPBasic driver example as part of the SmartMON series

If you don't want/need to follow the code examples and build your own simple driver for these RTC's (recommended option for a small size and robust implementation) I am sure that you can find already libraries for Arduino for them.

Happy breadboarding,
TJ.

Hi.
Thanks for your time and response!
There is something that confuses me!
What are SoftwareWire & HardwareWire?
My module is esp-01 and I should use GPIO0 & GPIO2 as SCL & SDA.
It is software or hardware?!