Int32_t Actually 16 Bit With Atmega328p And Arduino Home » Arduino Uint32_t Size » Int32_t Actually 16 Bit With Atmega328p And Arduino Maybe your like Arduino Uint32_t To Byte Array Arduino Uint8_t Buffer To String Arduino Uno Ble Example Arduino Uno Ble Library Arduino Uno Ble Shield Int32_t actually 16 bit with Atmega328p and Arduino Development Platforms atmelavr, vscode shadowmaster April 28, 2021, 9:49pm 1 I’m using the Atmega328p on the Arduino framework. I found out that even when explicitly using int32_t or uint32_t, the variable is actually only 16 bit. The reason is, that they are type defined to ‘unsigned int uint32_t’. The problem here, is that on the 8 bit AVR problem, ‘int’ is only 16 bit. The type defines are in ‘toolchain-atmelavr>avr>include>stdint.h’. Obviously I would expect it to be 32 bit like it is in the Arduino IDE. Is there something I am doing wrong, or is this a bug? I’m using VS Code, PIO 5.1.1 and Atmel AVR 3.3.0 maxgerhardt April 28, 2021, 9:57pm 2 Not reproducable. Running the code #include <Arduino.h> #define xstr(s) str(s) #define str(s) #s void setup(){ Serial.begin(9600); } #define PRINT_SIZE_OF(type) Serial.println("Size of " str(type) " is: " + String(sizeof(type)*8) + " bits"); void loop() { PRINT_SIZE_OF(int); PRINT_SIZE_OF(int32_t); PRINT_SIZE_OF(uint32_t); PRINT_SIZE_OF(int_least32_t); PRINT_SIZE_OF(uint_least32_t); PRINT_SIZE_OF(int64_t); PRINT_SIZE_OF(uint64_t); delay(1000); } outputs Size of int is: 16 bits Size of int32_t is: 32 bits Size of uint32_t is: 32 bits Size of int_least32_t is: 32 bits Size of uint_least32_t is: 32 bits Size of int64_t is: 64 bits Size of uint64_t is: 64 bits with the platformio.ini [env:uno] platform = atmelavr board = uno framework = arduino All fixed-width or at-least-width types work as advertised. Using packages and versions PLATFORM: Atmel AVR (3.3.0) > Arduino Uno HARDWARE: ATMEGA328P 16MHz, 2KB RAM, 31.50KB Flash DEBUG: Current (avr-stub) On-board (avr-stub, simavr) PACKAGES: - framework-arduino-avr 5.1.0 - tool-avrdude 1.60300.200527 (6.3.0) - toolchain-atmelavr 1.70300.191015 (7.3.0) shadowmaster April 28, 2021, 10:17pm 3 I don’t have the HW on me currently to test, but I will note, that for the board I have the ‘Atmega328p’ and not Uno and I do not have AVR dude. maxgerhardt April 28, 2021, 10:19pm 4 I can also treat my Uno board as board = Atmega328P in the platformio.ini and the output stays the same. (from docs). shadowmaster April 28, 2021, 10:23pm 5 Strange, all I can currently add is this image, which indicates that int32_t is typ defined to int shadowmaster April 29, 2021, 6:47am 6 I tested your code on the Atmega328p and could not reproduce my error either. Turns out, I made some incorrect assumptions: the first, was that ‘typedef int int32_t’ would mean, that it just gets set to an integer aka 16 bits on the AVR platform, while I don’t quite understand why this is not the case, this was not the root of my problem. My actual problem was my second assumption: putting the whole add operation of a 16 and 32 bit integer into a single cast is the same would work. It does not… What I had to do is cast only the 16 bit integer as a 32 bit one. Rookie mistake. Thank you max for the quick response and for the work all of you mods put in this community. I have yet to see a post without a single response as is too often the case in a lot of communities. Keep up the good work! Tag » Arduino Uint32_t Size What Does Uint32_t Do? - Programming Questions - Arduino Forum Uint16_t And Uint32_t Question! - Arduino Forum Type Definition For Uint32_t - Programming Questions - Arduino Forum Unsigned Int - Arduino Reference Data Types In Arduino - Sparkfun Learn Arduino-device-lib/pb_decode.c At Master - GitHub Truyền Các Số Kiểu Long, Int, Float Trong Giao Tiếp Serial (UART) Variables – C - Arduino Developer Resources Reliably Read Serial Data In C++ [closed] - Arduino - Stack Overflow Variable Types In Arduino IDE Arduino Store Int Into EEPROM - The Robotics Back-End Uint8 In C, Uint32_t Vs Unsigned Int, Uint32_t Arduino, UInt32.MaxValue Field (System) - Microsoft Docs .es/~alberto/arduino/SdBaseFile.cpp