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ESP32 Logging

ESP32 logging falls into the same category as the recent post about embedding binary content. It is about how logging on ESP32 is different from logging on ESP8266. Yet, as “logging” is a software topic (mostly) and “ESP32” describes hardware we need to be more precise with terms. Therefore, this post will look into how logging with the Espressif ESP-IDF has improved over plain NONOS SDK. The same goes for Arduino Core for ESP32.

Rest assured the old stuff still works on ESP-IDF. However, this post hopefully manages to convince you to improve your code by using the new features.

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Embed Binary Data on ESP32

pre-electronic binary code by dret

There is a reason the title of this post specifically says “Embed Binary Data on ESP32“. This suggests that it is different than embedding binary data on let’s say ESP8266. Yes indeed, that’s part of the story. The other is that to embed binary data on ESP32 you don’t need to jump through hoops anymore like on ESP8266. Instead, you will do what likely feels most natural: store the binary data in a file in the project directory and have the compiler slurp it from there. Easy as pie!

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The ESP8266 Spotify Remote – Engineering Challenges

Do you know this situation: you are listening to a playlist from Spotify on your stereo but just can’t figure out who is singing that song? Since you are sitting comfortably on your couch (too far away from your stereo) you think how this problem could be solved with some clever engineering. You quickly draw up a mental design in your head: a ESP8266 based device connects over the net to Spotify. Then every few seconds it downloads information about the currently played song. Maybe some cover art too and display it on a color display! It can’t be THAT hard, right? This post explains the challenges I faced when implementing the ESP8266 Spotify remote and how I solved them.

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Max deep sleep for ESP8266

max deep sleep for ESP8266

In light of our recent power-consumption related posts 1 & 2 it seemed logical to ask ourselves about max deep sleep for ESP8266. Yet, it took a comment from a curious reader to set things in motion. I replied

…the maximum value for a 32-bit unsigned integer is 4294967295 or 0xffffffff. Hence, the max deep sleep interval appears to be ~71 minutes.

You can’t argue with that first statement but the second is a bit in the air without clear evidence. My co-founder Dani quite rightly then asked “are you sure, didn’t they change that recently?” (“they” being Espressif and/or the Arduino devs).

So then, what is the current max deep sleep for ESP8266 i.e. the maximum duration the ESP8266 can sleep deeply – and still wake up afterwards.

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5 Hacks to Prolong your ESPaper’s Battery Run-Time

In the last post I showed you how you can use cheap hardware to get a reasonable good power consumption test rig. In this post we are going to use this tool to improve the runtime of the ESPaper significantly. The short trial and error cycle possible with this tool will let us validate several ideas for improvement in only very little time. Continue reading 5 Hacks to Prolong your ESPaper’s Battery Run-Time

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ESP8266: Monitoring Power Consumption

In this post I’m going to show you how you can monitor the power consumption of your battery driven (ESP8266/ ESP32) device. Measuring the power consumption over a full activity/ sleep cycle is the precondition to optimize your code for a longer battery runtime. Only with a reliable tool you can decide which code changes lead to less consumption. In a later post we’ll look at some tweaks we can apply to the code to get a few more days out of the battery. Continue reading ESP8266: Monitoring Power Consumption