I started to dig a bit more into the Iot development network from Espressif with the intention to slowly learn something new. All the official examples of Mesh lights, ESP32-Camera and ESP-WHO that presents a preliminary version of face recognition are built on the top of the IDF.
So sooner or later, I think will be the official way to do “internet of the things” devices with these Boards. But I’m still not ready for it, I need to do simple examples and experimenting before taking over and do something for real.
So the first things I tackled on is to take this libraries “as is” and use them in existing Arduino framework projects. And it’s fully possible, below is a small example about this using the TTGO Camera with Pir sensor
As an introduction I would like to make clear that I’m not a C++ advanced coder or IoT professional, I do this just because it’s a challenge, and because it’s a lot of fun compared to my 9 hrs/5 days a week web developer doing PHP and Admin panels for clients in Germany. Two months ago I started tinkering with SPI Cameras and the Espressif systems boards and that’s how this open source project was born. So far I was using Arduino since I do not need a super IDE, sometimes I also edit the code with vi or gedit instead of open a monster IDE that will eat your CPU alive. But gladly this is not the case. I was since long looking for a competitive alternative to Arduino when this github issue on the FS2 Camera Project called my interest:
tablatronix commented 8 days ago
I had to manually install this button library as it is not in platformio , is it in arduinos?
And that’s how after a few clicks I discovered Plaftormio.org that according to their home page it’s an open source IoT ecosystem. But what interested me more than this is the subtitle: “Cross-platform IDE and unified debugger. Remote unit testing and firmware updates“
So instead of answering tablatronix issue, I started installing this new IDE, that happened in a breeze. 1. First thing is to install the VS CODE Version. I choosed the Visual Studio code option since it has more features. Microsoft’s Visual Studio Code is the base and PlatformIO is built on the top of this.
2. Go to “Extensions” and install PlatformIO IDE “Development environment for IoT, Arduino, Espressif (ESP8266/ESP32)”
3. In my case since I used Arduino IDE before, go to PlatformIO alien face logo and select “Import project from Arduino”. Then select the folder where your Arduino project is and PlatformIO will create a Workspace for you with all the necessary structure.
4. Adjust serial monitor baud rate. If you are using Espressif chips edit platformio.ini and add the following line at the end:
monitor_baud = 115200
This will make your serial work in the right baud rate for ESP8266 /ESP32 (Serial is the plug icon in the bottom just before the Terminal > icon)
5. FS Data. If you are using SPIFFS that in Arduino is the /data folder inside your sketch you will notice that in PlatformIO this folder needs to be at the root level. So you can simply move it one directory above. To upload SPIFFS data use the following command in the terminal:
pio run --target uploadfs
IMPORTANT: As difference with Arduino if you try to save a file in /1.JPG here you will get it saved on: /spiffs/1.JPG so create this folder on /data or you will get; VFSFileImpl(): fopen(/spiffs/1.jpg) failed
6. Libraries in PlatformIO live inside a folder on your project called .piolibdeps Thanks god, they are not distributed on 3 different parts, like it happens with Arduino (Some in Arduino/libraries, some in Programs/Arduino/libraries and so on) but are there available for you in just one place :) To install a new library is very easy, just go to PlatformIO.org/lib and type the name of the library to search. If found copy the resultant line in the Terminal just like point 5 and the IDE will look this up for you and download it using github to the .piolibdeps folder.
pio lib install "WifiManager"
Sometimes you will need a library in a special branch and there is also an easy way to do this. Just use :
pio lib install <repository#tag>
// Install development version of WifiManager library pio lib install https://github.com/tzapu/WiFiManager.git#development
7. If you use Arduino before it’s possible that you used some of it’s constants. So if your sketch compiles, but it does not runs like expected try to add this include line at the beginning
As a footer note I must make clear that it takes some time to get accustomed to the new IDE. But it comes with a great benefit as it shows you much better C++ warnings, it’s prettier to use, and has the advantage that you can Ctrl+Click and navigate between different classes. Something that it was not possible to do with my old IDE. And the most beautiful update is that all libraries are in a single place per Project, like it should be, leaving you a clear idea of how much code and dependencies you are adding into your sketch.
In FS2 project porting it to the ESP8266 Wemos board this happened like a breeze. And it was just the fact of upgrading my code to use OneButton library. adding the include Arduino.h and that is. After uploading SPIFFS data and the new code, the camera was ready to be used. Now it’s not always that easy. trying to compile the same code to an Heltec ESP32 board, I got SPI communication issues with the camera and I’m still fighting with it.
UPDATE: I found what is going on here, and it’s that there are some problems with my sketch that uses I2C and wire library to comunicate with the Camera on the Heltec ESP32 environment. Error message is: i2cCheckLineState(): Bus Invalid State, TwoWire() Can’t init. I solved it updating the platformio.ini configuration file to use: board = lolin_d32 So using this board it compiles and works correctly. No idea why it does not using heltec_wifi_lora_32 I will have to research more.
Additional links of interest:
Source filter: src_filter This option allows to specify which source files should be included/excluded from build process. It could be useful to keep the same core for ESP8266 and ESP32 but including different files to support both. So far I’ve been using 2 different branches something that is hard to maintain for obvious reasons.
Library dependencies: lib_deps declaration in platformio.ini Like composer for PHP, this IDE offers a way to declarate your libs in the ini file. To check how a professional software for 3D-printing does take a look in Marlin configuration file. This is a very important point to keep in mind since after the lib_deps list is correctly added and tested, people testing your code just need to hit “build” to download them, saving a huge amount of time.
New Project: ESP-IDF Component for epapers
Lately I’ve started to spend time trying Espressif’s own IoT development framework: ESP-IDF. At the moment of updating this post in version 4.0 And I must say that I like it a lot!