How to get rid of all save() flash memory code?

[espruino-discuss]

Posted at 2016-01-07 by UliMerkel

I experiment with some standalone datalogger which issues save() internally for data persistency.

When I use reset(), the code is still in the flash memory and can be used with load(). That's OK.
But what is the correct way to reset the flash memory to a neutral state?

For the moment in time I use "reset();save()"

But when the PICO is connected to a USB I get a constant green LED and the dump() says:

dump()
setSleepIndicator(B12);
digitalWrite(B12,1);
=undefined

1st question:
So is there a way to clear the flash so there is no "setSleepIndicator(B12); digitalWrite(B12,1);" ?

2nd question:
Is there a way for a 'mute' save().
save() generates a lot of output to the console; in standalone this may overflow the buffers.

Greetings from Frankfurt/Germany, Uli

[gfwilliams]

Posted at 2016-01-07 by @gfwilliams

That's odd. Does it work better if you do reset() and save() as two separate commands? I think it says in the documentation, but reset() will reset the chip without actually saving anything.

There isn't a way to 'mute' save I'm afraid, but using save() to save data that changes all the time isn't a good idea anyway - it rewrites all of flash each time, so it can wear out the flash memory inside Espruino relatively quickly.

Have you seen the Flash EEPROM Library - that will allow you to save data to flash memory, but it does so using a simple 'journalling' system which means that all of the flash memory gets used up before it is erased.

[espruino-discuss]

Posted at 2016-01-07 by UliMerkel

Hi Gordon,

looks like the setSleepIndicator() is not affected by the save() for whatever reason.
I just had a setSleepIndicator("") and the dump() doesn't show the code any more after the save.
Strange.

thanks for the link to Flash EEPROM Library, I will have a look.

For codingnights, I just create a sequence of experiments with the 'bare' PICO
so even newbies can create great effects with just a little bit of javascript in 2hrs time.
Just a handful of simple statements and try to make creative use of a button and 2 LEDs.
"Single Button Combination Lock" is a great example what can be achieved.

[espruino-discuss]

Posted at 2016-01-08 by UliMerkel

Hi Gordon,
it looks like there is a little bug with the setSleepIndicator(LED1) which is not cleard with reset():
I set the Indicator and run a save(); but after a reset() and a following save(), the dump() still showed the setSleepIndicator(B2).
After calling setSleepIndicator() with undefined argument the dump is empty. So looks like this resists the reset() processing:

>dump()
setSleepIndicator(B2);
digitalWrite(B2,1);
=undefined
>reset();
=undefined
 _____                 _
|   __|___ ___ ___ _ _|_|___ ___
|   __|_ -| . |  _| | | |   | . |
|_____|___|  _|_| |___|_|_|_|___|
          |_| http://espruino.com
 1v84 Copyright 2015 G.Williams
>save();
=undefined
Erasing Flash.....
Writing...
Compressed 81600 bytes to 854
Checking...
Done!
>dump()
setSleepIndicator(B2);
=undefined
>setSleepIndicator()
=undefined
>dump()
=undefined

[gfwilliams]

Posted at 2016-01-08 by @gfwilliams

Ahh, thanks! I just fixed this, so it'll be in the next version