Returning a Hex value from an integer

DavidN_ — Sat, 07 Mar 2009 05:32:44 GMT

I am using the 16 bit 9S12C128 MCU. I wrote this simple code to return a hex value from an integer input.

word dec_to_hex(signed short number)
{
word hex_value;
hex_value = number;

return hex_value;
}

What I would like to know is, does this return a 16 bit hex value (i.e. input = 32767, returns 0x7FFF; input = -32768, returns 0x8000)? I can't really check the output because when I use "%d", I get an integer value; and when I use a "%x", I get the hex value.

The reason for this is so that I can output the hex value to a DAC. Also, the data type "word" in a 16 bit MCU means that one word is 16 bits and the data type "dword" means 32 bits?

I have googled this but I could never get a clear answer. Any help is appreciated. Thanks in advance.

Re: Returning a Hex value from an integer

Lundin — Mon, 09 Mar 2009 15:30:26 GMT

It isn't clear whether "word" is defined as signed or unsigned integer. It is not an ISO C type, it is a non-standard type, so the answer can only be found in your compiler docs. What compiler are you using?

My advise would generally be to avoid all untrusted integer types, including plain "int", "short" etc, and thereby avoid all signedness and porting issues. Use something like this instead:

typedef unsigned char uint8;
typedef unsigned short uint16;
typedef unsigned long uint32;
typedef signed char sint8;
typedef signed short sint16;
typedef signed long sint32;

topic Returning a Hex value from an integer in CodeWarrior for MCU

Returning a Hex value from an integer

Re: Returning a Hex value from an integer