topic Re: HCS08GT60 __isflag_int() in 8-bit Microcontrollers

HCS08GT60 __isflag_int()

StevePratt — Wed, 29 Mar 2006 05:00:46 GMT

I am trying to use the __isfalg_int() macro to poll the level of the ext int pin, I keep getting compiler errors? How can i do this? Is the following format correct?

static void test(void)
{
   if (__isflag_int()) goto label;


label:
}

Warning : C1801: Implicit parameter-declaration for '__isflag_int'

GPS_Buoy_Receiver.c line 1680

Error : C2801: ';' missing

GPS_Buoy_Receiver.c line 1683

Error : C2450: Expected: { IDENT auto break case const continue default do extern for goto if register return static switch typedef
volatile while __asm __interrupt

GPS_Buoy_Receiver.c line 1684

Error : Compile failed

Re: HCS08GT60 __isflag_int()

alex_spotw — Wed, 29 Mar 2006 06:15:09 GMT

Hi:

Chances are you're not including the .h file where the _isflag_int() function is declared (which is indicated by the Warning).

Warning : C1801: Implicit parameter-declaration for '__isflag_int'

I would suggest enable the compile option 'Error on Implicit declaration', which will catch these errors and will prevent many headaches.

Also, it is strongly suggested not to use the 'goto' statement. It leads to bad programming habits.

I would do something like

static void test(void)
{
if(EXT_INT_GetVal() == FALSE)
{
// External INT pin is LOW
// Do action
}
else
{
// External INT is HIGH
// Do other action
}
}

The EXT_INT_GetVal() function can autogenerated if you have Processor Expert. Otherwise, you can create you own version by checking the IRQF flag in the IRQSC register (assuming you enable the Ext IRQ function and set up the correct edge/level).

Regards,

Alex R.

Message Edited by alex_spotw on 03-28-200604:16 PM

Re: HCS08GT60 __isflag_int()

CrasyCat — Wed, 29 Mar 2006 17:10:37 GMT

Hello

Which processor are you targeting?

Intrinsic function __isflag_int is available in CodeWarrior HC08 V5.0 and V3.1.

I have used following code there and it links without trouble:

if(__isflag_int())
{
var = 2;
} else
{
var = 1;
}

CrasyCat

Re: HCS08GT60 __isflag_int()

CompilerGuru — Thu, 30 Mar 2006 01:55:27 GMT

as final comment, after all the real things have been said by the other repliers.
The original sample does not compile because in ANSI-C, there has to be a statement after a label. So "void bug() {l:}" is illegal, void ok(void) { label:; } compiles.
But try to avoid labels & goto in the first place.