ESP8266 Community Forum

- Fri Oct 09, 2015 4:47 pm #30978 Compiling a sketch (for "Generic ESP8266 module") I get:

Sketch uses 321,784 bytes (74%) of program storage space. Maximum is 434,160 bytes.
Global variables use 64,424 bytes (78%) of dynamic memory, leaving 17,496 bytes for local variables. Maximum is 81,920 bytes.
Low memory available, stability problems may occur.

This seems to be reported on going past 75% storage memory usage - is this just a hangover from the AVR processor limitations? Or does the ESP8266 implementation really need 18k or so of memory? I'm hoping not.

- Sat Oct 10, 2015 8:29 pm #31072

is this just a hangover from the AVR processor limitations? Or does the ESP8266 implementation really need 18k or so of memory? I'm hoping not.

No, it is not a hangover: there is no AVR-centric stuff in the ESP8266 implementation, even the compiler is completely different.

There is a RTOS engine linked into the environment automatically to ensure that the ESP8266 radio and protocol critical routines get cpu time. The Arduino'ish code runs separately and must relinguish time so the RTOS can switch pending tasks. This all works amazingly well.

The compiler warning about memory is just that, a warning. The complexity of your sketch and function calls, call-backs, and dynamically sized objects(not a good idea) will determine how much free space is actually needed.... this means stress testing by you.

Ray

My Projects https://www.hackster.io/rayburne