Write Flash Timeout

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Re: Write Flash Timeout

By martinayotte
- Thu Jun 25, 2015 5:12 pm #21693 As I've mentioned in other the three other threads where you misleaded people with wrong information about this GPIO2 issue :

I prefer trusting a spec sheet than people testimonies. the Boot process table from the link https://github.com/esp8266/esp8266-wiki ... ot-Process is proably a copy/paste from Espressif specs. It should NOT be amended to please end-users.
Been in electronic engineering for decades, the four different possible connections for an input : L, H, X and NC. BTW, X doesn't mean floating, it means "irrelevant". Not connecting a X input can still be troublesome, since EMI/RFI can disturb the input, and even destroy it if EMI/RFI is too high. We should never leaving inputs floating, except if specs says NC.

Additionnally, if the table says to put it to HIGH, even if there is currently no mode in the table that use it with LOW, it doesn't mean Espressif can decide in a future to use that for an additional mode of boot process, let's says for example thru an I2C bus. So, to respect backward compatibity, we should follow the specs to the "letter".

BTW, and I've just try it out : if GPIO2 had a X instead of H, then that would mean that we can place to LOW, but right now, in such case it does NOT boot any more ! If leaving it floating works, it is simply that, like in the old days of TTL, floating is quite the same as HIGH (except about EMI potential issue). Right now, it is confirmed : Espressif really spec it that a HIGH level is REALLY required on GPIO2 !

EDIT : I have about 2 ESP01, 1 ESP03, 6 ESP12 and 2 ESP12E. All of them are hookup with PullUp on GPIO0 and GPI02. There are all working fine because I've followed the true-table mentionned above. (BTW, I'm not flaming you, I never said that left GPIO2 floating won't work, I've just said that it is not a good pratice, and it is not intended to be use like that according to basic rules.)
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Re: Write Flash Timeout

By tytower
- Fri Jun 26, 2015 12:16 am #21716 This guy obviously cant accept that he might be wrong in calling me wrong . Go whichever way you want, but high or floating are definately correct and no-one is wrong . I am fed up with his stupidity-same post four threads
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Re: Write Flash Timeout

By martinayotte
- Fri Jun 26, 2015 8:12 am #21754
tytower wrote:This guy obviously cant accept that he might be wrong in calling me wrong . Go whichever way you want, but high or floating are definately correct and no-one is wrong . I am fed up with his stupidity-same post four threads


Ehhhh ! Guy, look and re-read my post !!! I've never flamed you, I have simply stated the true about facts and basic that any electronics engineers agree with. I'm part of those, NOT you ! Simply go back to school to learn those basics. If I posted four time the same things, it is simply because you have posted so many time the wrong argument that GPIO2 should NOT be pulled-up but left floating, you even pushed your argument saying we need to change this Wiki Boot Process table to put an X instead of H, for which I prove it to you yesterday that X means I can decide to put it to L without any effect. Who is REALLY WRONG here ?
You says that I have posted "stupidity" ? Ask real engineers to see if what I posted has any thing wrong, prove it !
And ask yourself about you own posts if they are stupid such the following :

tytower wrote:If I wire up 2 1.5 volt batteries in series I get 5 volts
If I wire up 2 more and put them in parallel you will find that an acceptable 5 volt supply

First 2x1.5V != 5V, Secondly, I hope you never did that with Lithium batteries in parallel ! You can ignite fire in your house !

And here is another one from viewtopic.php?f=13&t=3533&p=21359&hilit=arduino.cc#p21359 :
You will have to add an interupt somewhere . See Arduino.cc interupts.

Did you ever think that the UART is also in Sleep Mode ?
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