How to write an unsigned char into the upper byte of an int???

[vividmusic]

Posted on February 03, 2004 at 10:28

How to write an unsigned char into the upper byte of an int???

[vividmusic]

Posted on February 02, 2004 at 02:12

Greeting people!!

this is probably easy but how do you do it in c?

- write an unsigned char (byte) into the top byte of an int (2 bytes)?

im using the cosmic compiler

i guess you could do

int = char;

int <<= 8;

is there a quicker way or is that it?

thanks for your time

chris

[parveen]

Posted on February 02, 2004 at 08:54

Try using unions

union

{

unsigned int MyInt;

unsigned char MyByte[2];

}A;

Hope this helps

Regards,

PraveenG

[vividmusic]

Posted on February 02, 2004 at 20:27

Thanks it good to learn something new

chris

[luca239955_st]

Posted on February 03, 2004 at 10:28

Using a shift will produce

int_var = char_var << 8;

ld x,_char_var

clr a

ld _int_var,x

ld _int_var+1,a

that is, will also clear the LSB of the int you are moving the char into.

Another possibility is to use pointers:

*(char *)&int_var = char_var;

ld a,_char_var

ld _int_var,a

this will leave the LSB unmodified.

Hope this helps.

Luca