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[on:]

Hi!

how can i get an 16 bit signed int in arduino Due?

i'm working with 16-bit i2c and 32 bit integers make my life very dificult.

word is 16-bit, but it is unsigned.

Please, help me.

[Reply #1 on:]

i forgot!

It would be great to have a data type table for Arduino Due.

[Reply #2 on:]

I would encourage you to use stdint.h. This has types such as uint16_t, int16_t etc if you need to be explicit about bit widths.

[Reply #3 on:]

Thank you!

[Reply #4 on:]

As a side note, use the sizeof() function if you're not sure how many bytes a data type is.

[Reply #5 on:]

Code:

#include <stdint.h>

void setup() {
  Serial.begin(96200);
}

void loop() {
  Serial.print("sizeof(byte)="); Serial.println(sizeof(byte));
  Serial.println();
  Serial.print("sizeof(char)="); Serial.println(sizeof(char));
  Serial.println();
  Serial.print("sizeof(short)="); Serial.println(sizeof(short));
  Serial.println();
  Serial.print("sizeof(int)="); Serial.println(sizeof(int));
  Serial.println();
  Serial.print("sizeof(long)="); Serial.println(sizeof(long));
  Serial.println();
  Serial.print("sizeof(long long)="); Serial.println(sizeof(long long));
  Serial.println();
  Serial.print("sizeof(bool)="); Serial.println(sizeof(bool));
  Serial.println();
  Serial.print("sizeof(boolean)="); Serial.println(sizeof(boolean));
  Serial.println();
  Serial.print("sizeof(float)="); Serial.println(sizeof(float));
  Serial.println();
  Serial.print("sizeof(double)="); Serial.println(sizeof(double));
  Serial.println();
  Serial.print("sizeof(int8_t)="); Serial.println(sizeof(int8_t));
  Serial.println();
  Serial.print("sizeof(int16_t)="); Serial.println(sizeof(int16_t));
  Serial.println();
  Serial.print("sizeof(int32_t)="); Serial.println(sizeof(int32_t));
  Serial.println();
  Serial.print("sizeof(int64_t)="); Serial.println(sizeof(int64_t));
  Serial.println();
  Serial.print("sizeof(uint8_t)="); Serial.println(sizeof(uint8_t));
  Serial.println();
  Serial.print("sizeof(uint16_t)="); Serial.println(sizeof(uint16_t));
  Serial.println();
  Serial.print("sizeof(uint32_t)="); Serial.println(sizeof(uint32_t));
  Serial.println();
  Serial.print("sizeof(uint64_t)="); Serial.println(sizeof(uint64_t));
  Serial.println();
  Serial.print("sizeof(char*)="); Serial.println(sizeof(char*));
  Serial.println();
  Serial.print("sizeof(int*)="); Serial.println(sizeof(int*));
  Serial.println();
  Serial.print("sizeof(long*)="); Serial.println(sizeof(long*));
  Serial.println();
  Serial.print("sizeof(float*)="); Serial.println(sizeof(float*));
  Serial.println();
  Serial.print("sizeof(double*)="); Serial.println(sizeof(double*));
  Serial.println();
  Serial.print("sizeof(void*)="); Serial.println(sizeof(void*));
  Serial.println();
  delay(10000);
}