Hi guys, I'm not very expert with arduino and with programming in general; I make a CPS (Concented Solar Power) for my thesis ( i'm becoming a mechanical engineer) and i'm trying to develope an automated system for the Solar Traking and for putting temperature data online on a chart. Every thing …

[image] ricca30: OK so what I did it's basically good..I'll try to put all the include on the cpp... don't know what this means [image] ricca30: extern Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); the above, the definition/constructor is needed in the .cpp file …

Thank guys, I miss a few things like the code to put data on web( already tested alone) And 2 temperature sensor. l'll try to share the code.. Main one #include "PINOUT.h" #include "FS.h" #include "SC.h" #include "PrintTime.h" boolean FS = true ; const char* ntpServer = "pool.ntp.org"; cons…

[image] ricca30: Concented Solar Power Concentrated.. Sorry wrote it so fast..

Yep sorry, it was Definition not declaration sketch\FS.cpp.o:(.bss.display+0x0): multiple definition of `display' sketch\Controller.ino.cpp.o:(.bss.display+0x0): first defined here sketch\PrintTime.cpp.o:(.bss.display+0x0): multiple definition of `display' sketch\Controller.ino.cpp.o:(.bss.displ…

[image] anon73444976: extern Have I to write it? where?

[image] ricca30: Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); the above in displaydef.h causes display to be defined in every .ino/.cpp file displaydef.h is included in i think display can be defined as an extern in the .h extern Adafruit_SSD1306 display;

So like this.. Still not working #ifndef displaydef_H #define displaydef_H #include <SPI.h> #include <Wire.h> #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h> #define SCREEN_WIDTH 128 // OLED display width, in pixels #define SCREEN_HEIGHT 64 // OLED display height, in pixels #define SCREE…

[image] ricca30: extern Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); no like this [image] gcjr: extern Adafruit_SSD1306 display;

[image] gfvalvo: See My Reply #5 Here OK so what I did it's basically good..I'll try to put all the include on the cpp...

[image] ricca30: (SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); Without " (SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1); " it's not working, it says : sketch\Controller.ino.cpp.o:(.literal._Z5setupv+0x10): undefined reference to display'`

First try with .h and .cpp, Multiple Definition issue

Projects Programming

gfvalvo May 15, 2021, 12:44pm 12

See My Reply #5 Here.

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First try with .h and .cpp, Multiple Definition issue

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