1

I am using stm32f407vg and there is a library called HAL library however there is a statemet or definition not sure to return an error message and it like return 0x00U or 0x01U if certain condition met so what is the purpose of those U's i wonder ?

Ahmed Akif Hekimoğlu
  • 13
  • 5
  • does this answer your que: https://stackoverflow.com/questions/9029974/what-does-u-mean-after-a-number – roottraveller Sep 04 '20 at 12:41
  • 1
    Does this answer your question? [Meaning of U suffix](https://stackoverflow.com/questions/4380691/meaning-of-u-suffix) – 89f3a1c Sep 04 '20 at 12:42

2 Answers2

-1

It means that it is an unsigned number.

(Looking for some source to update my answer, I found this question, so this might be a duplicate).

89f3a1c
  • 1,430
  • 1
  • 14
  • 24
-1

u is the "unsigned-suffix" and on its own makes an integer constant unsigned int, unsigned long int or unsigned long long int depending on the value.

In the C standard, see section 6.4.4.1 (Integer constants) paragraph 5.

Paul Hankin
  • 54,811
  • 11
  • 92
  • 118