Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By darethehair
#55442 NOTE: I still consider myself a newbie after only working with NodeMCU stuff for a week or so!

As my very first (and successful!) NodeMCU project, I connected a DHT22 and BMP180 sensor to a LoLin V3 NodeMCU board, and it works fine -- after powering off/on it immediately makes the measurements available to me at the IP address I coded in the lua code I used.

I had separately ordered a Witty Cloud NodeMCU, since I was intrigued by the extra built-in features i.e. light sensor and RGB light. Well, it was fun to play with that, but I have concluded that it is a poor substitute for a 'regular' NodeMCU, at least for my purposes (less pins, hassle to plug in sensors when using the UART/USB interface, etc.). Anyways, I took my code from the LoLin board, modified it to work with my BME280 chip, and got it to work as well -- but it does *not* respond immediately after a power-on sequence -- I have to press the 'reset' button, or enter 'node.restart()' while connected to the serial port. In other words, this device does not (for me) nicely recover from a power outage, making it useless to me. In the meantime, I have ordered a LoLin V3 NodeMCU as a replacement, since it appears to not have this problem. Am I doing something silly?
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By Barnabybear
#55450 Hi, I've used various ESPs (no development board) with a CH340 serial adapter none will boot if the CH340 is connected but not powered. Guessing the ESP powers up faster than the CH341 on that board. You could try hacking it with some caps, but I found the wemos / clones (hard to tell) boot up ok from 5V as opposed to the USB.
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By darethehair
#55452
Barnabybear wrote:Hi, I've used various ESPs (no development board) with a CH340 serial adapter none will boot if the CH340 is connected but not powered. Guessing the ESP powers up faster than the CH341 on that board. You could try hacking it with some caps, but I found the wemos / clones (hard to tell) boot up ok from 5V as opposed to the USB.


Just to be clear, my Witty Cloud NodeMCU powers up just fine, and (after setting the static IP address in my lua code) it responds perfectly to 'ping' commands, but the other wifi communication (e.g. HTTP, wget, etc.) refuse to respond until after a reset. So it's almost as if the 'init.lua' default program is not being properly called until I do a reset (?).