ESP8266 Community Forum

- Tue Apr 12, 2016 10:48 am #45367

- power-on-time-hardware. They use a pull-up with 100nF in series to ground, and feed this into reset-input. I do the same but feed it into CH_PD-input.

Although not related with your issue :
CH_PD (or sometime named EN) is only to allow PowerDown mode, it is not a reset pin. So, there is no need for capacitor on this pin, only a PullUp to VCC.
Do you have PullUp on RES pin too ?

- Wed Apr 13, 2016 1:11 am #45403 @martinayotte: I did not know the CH_PD pin was to enable PowerDown. I now see the abbreviation...
To answer your question: yes I do have a pull-up (15k) resistor on the RES pin.

I came across another difference between my hardware and the nodeMCU dev board:
My hardware can be serial flashed with the option QIO (and DIO), where the dev board has to be DIO flashed.
At this moment I am running a new test where I flash my hardware with DIO option, although I don't expect to see any difference.

- Thu Apr 14, 2016 9:10 am #45474 I have run several tests since my last post.
I have compiled with the SPI mode set to DIO and serial flashed (also in DIO mode) 16 modules.
These have run for about a full day, performing a restart every 2 minutes, without freezes.

To be sure, I reflashed (serial) them back with QIO mode and after about 10-15 minutes the firsts start to freeze.
For me this would be enough evidence DIO mode would be a solution to my issue.
It is too early to claim this certainly is the cause of the problem, further inverstigation would be needed.

I have run another test where I have compiled and serial flashed the modules in QIO mode (which would be a real life system with about 250 esp8266 modules). Then compiled the same software with DIO option and OTA updated the 16 modules on my test bench with the new firmware. Unfortunately, the modules still start to freeze, so it appears to be mandatory to serial flash in DIO mode.
This means I have to open about 250 enclosures, connect programmer, flash the module in DIO mode, close the enclosure. This all while laying on my back on the ground while reaching over my head.

Unless.... someone would have a better solution (or cause) of my problem

- Thu Apr 14, 2016 10:18 am #45477 The configuration for the flash's SPI mode & speed is located along with the bootloader in the first flash sector.
So yes, regular OTA upgrades will not alter these settings.
However since sector 0 is not used any more, after your firmware is loaded, you should be able to write a firmware that reads sector 0, modifies the settings, writes the changes and reboots.

These links you should help you figure out what you have to modify:
http://richard.burtons.org/2015/05/17/e ... t-process/
https://github.com/themadinventor/espto ... ol.py#L689