Olimex Support Forum

Microcontrollers => ESP8266 => Topic started by: gerrikoio on August 21, 2015, 02:30:46 AM

Title: Making the most of the 2MB of flash
Post by: gerrikoio on August 21, 2015, 02:30:46 AM
I've just purchased the MOD-WIFI-ESP8266 and considering the MOD-WIFI-ESP8266-DEV. Now trying to build up my understanding of possibilities.

I've used TI's cc3200 before and was able to flash html, jpegs onto flash memory to make a pretty looking web server page (ok did not leave much for micro controller code etc.) but it is better than a blank page. Now with 2MB of code one would think that you can do something similar here too but how....

What else can be done with the 2MB of flash memory.

For example, is it possible to write to flash (e.g. store data from UART and/or GPIO pins and/or user inputs from web browser page etc.) during runtime for nv (non volatile) data logging etc. If so how.
Title: Re: Making the most of the 2MB of flash
Post by: Lurch on August 21, 2015, 01:34:40 PM
Flash is not EEProm, you need to erase blocks etc. Read Espressif's 99A manual on Flash RW as a start.
For temporary storage, you probably want an I2C or SPI chip connected.
You can store static web pages/data in the flash. Or different boot files.
Check GitHub for http and boot examples.
There isn't a community for ESP8266 like Arduino has, but then it only costs a few bucks.
Also be sure to look at updates and examples on http://bbs.espressif.com/
Title: Re: Making the most of the 2MB of flash
Post by: gerrikoio on August 21, 2015, 01:54:13 PM
@Lurch, thank you for your reply and the references.

This is what I was thinking about, re data storage using non volatile memory. With cc3200, it uses flash rather than EEProm. It's messy but it's possible: http://forum.43oh.com/topic/5972-non-volatile-memory-options-for-cc3200/ and as you say you have to erase blocks etc.