topic Re: Assembly code porting from GCC in S12 / MagniV Microcontrollers

Assembly code porting from GCC

embitel — Thu, 05 Jul 2012 13:23:10 GMT

Please let me know how to port the below GCC code to CodeWarrior (HCS12).

__asm__ __volatile__ ("tsta\n"
"bne ccnp_skip\n");

Thank you

Deepak

Re: Assembly code porting from GCC

CrasyCat — Thu, 05 Jul 2012 13:46:58 GMT

Hello

Which compiler are you using here?

CodeWarrior? Anything else?

Also I assume you intend to embed assembly code inside of an ANSI C function. Am I right?

CrasyCat

Re: Assembly code porting from GCC

embitel — Thu, 05 Jul 2012 13:54:26 GMT

Yes, you are right. I am using Codewarrior compiler and this code I want to embed in a C function.

Re: Assembly code porting from GCC

embitel — Thu, 05 Jul 2012 13:55:36 GMT

Yes, you are right. I am using Codewarrior compiler and this code I want to embed in a C function.

Regards,

Deepak

Re: Assembly code porting from GCC

kef — Thu, 05 Jul 2012 16:57:28 GMT

__asm__ __volatile__ ("tsta\n" "bne ccnp_skip\n");

You need to determine what was in A register in GCC code just above ^^ this line. Certainly A had to be loaded with some variable or maybe higher order byte of 16 or 32 bits variable. It could be also top most byte of some floating point variable and this asm line could be used to perform quick check for positive floating number is not to small or smth like that. Provided A was loaded with 8 bit variable var, code may look like this

a) in case ccnp_skip label is below __asm__ line

if( var == 0 )

{

// code between __asm__ and ccnp_skip label

}

ccnp_skip:

b) in case ccnp_skip label is above __asm__

do{

// code between __asm__ and ccnp_skip label

} while (var != 0);

Re: Assembly code porting from GCC

embitel — Thu, 05 Jul 2012 17:15:55 GMT

Thanks Kef... It works...