My learning thread - thanks everyone

guys. another question..

what is the exact explanation why we use like this

variable1 = (s32)variable2; 

what actually the effect of s32? what is the difference is i use s16?

what actually the effect of s32? what is the difference is i use s16?

romel_emperado

(s32) is a "cast".. usually used when you transfer a value between variables of different sizes.
It tells the compiler that you know about the miss-match and take responsibility for any errors.
In this case variable1 is a 32 bit signed variable and variable2 isn't.

The effect of using (s16) will depend on what variable2 is, and the compiler may object.

(s32) is a "cast".. usually used when you transfer a value between variables of different sizes.
It tells the compiler that you know about the miss-match and take responsibility for any errors

thanks experimenterUK

guys what is the purpose of adding bitwise AND 0x0FF in the expresion below?

for example if the sAlt.altitude = 111

in binary 111 is 0110 1111 so

0110 1111
1111 1111
___________
0110 1111 ---answer is still 0110 1111

so what is the purpose of 0xFF ??

temp[3] = sAlt.altitude & 0xFF;

temp is a byte array (i byte per element) and altitude might be a s16 (a 16 bit variable) so you have to send this variable in parts to store it a byte array.

sAlt.altitude & 0xFF will truncate/mask the upper 8 bits of variable and lower 8bits will be stored in temp array.

0x1234 & 0xFF = 0x34
0x1234 & 0xFF00 = 0x1200 //truncate lower 8 bytes.

thanks for the explaination ajay. Another knowledge

How did you study like that before? Your awesome! Hehe

haha... well i say practice? try it..

haha thanks! i will
i will be engaged a lot of practice because some projects are approaching..

I'll ask again here if i have some doubts. Hehe

guys I have question..

Im how do I accurately count/determine the maximum value it can hold of this data type?

u8 = unsigned char
s8 = char
u16 = unsigned short / unsigned int
s16 = short / int
u32 = unsigned long
s32 = long

i just always estimating when I program something.... hehe