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ESP8266 Wemos D1 min pro - how to change TCP_SND_BUF?

I finally figured it out the hard way : https://github.com/esp8266/Arduino/discussions/8616 Install Git for windows (https://git-scm.com/download/win) Install MinGW for windows (https://sourceforge....
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ESP8266 Wemos D1 min pro - how to change TCP_SND_BUF?

No, you can't. The macro you are trying to tweak is for reference only and does not control the size of the buffer. On the ESP8266 the IP stack (and much of the rest of the system) is precompiled as ....
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Determining ArduinoJSON document size based on file size

There is unfortunately no way to predict the size of the JsonDocument from the file size alone. As a workaround, I suggest that you allocate a very large memory pool and shrink it after ...
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PWM on Wemos D1 Mini (esp8266 chip) does not work

At one point analogWrite as it was implemented in the esp8266-core had defaulted to a 10-bit range. This is no longer the case. It defaults to 8-bit range now. In any case analogWrite is implemented ...
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PubSub'a - KeepAlive function not as expected

This is the correct behavior. The “last will” message is sent by the broker when it detects that the client has gone away. When you reset the ESP8266, the original connection to the broker is ...
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HD44780 display incorrectly black-on-blue instead of white-on-blue

I have a similar LCD display (I assume it's virtually identical, hard to confirm). In my case, driving the display VCC (and SCK and SDA) at 3.3v produced the same behaviour you described (dim black ...
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ESP8266 - How to recieve UDP multicast packet?

I think you need to call Udp.begin(multicastPort); right before calling Udp.beginMulticast(WiFi.localIP(), multicastIP, multicastPort); At least that's what did the trick for me.
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ESP8266 soft resets when using a GPIO Expander

In the end the answer to the problem is the update frequency of the pins that drive the e-paper display: The original waveshare library (as linked in the post) does the following to send data to the ...
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Connecting multiple topics- MQTT

You can make life easier if you arrange your topic names hierarchically. As an example suppose we have a multimedia controller that accepts various commmands: mediaserver/set/volume mediaserver/set/...
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Non-blocking MQTT library

I had the same question and found an mqtt library that is completely non-blocking. https://github.com/marvinroger/async-mqtt-client You need to manually install it and the docs give instructions: ...
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