Another frustrating day...

Very simple little program in HITECH C for the 12F675, randomly produces
this very strange error:

 aspic "\"--edf=3DD:\Program Files\HI-TECH Software\
Error   [800] C:\DOCUME~1\JAMESN~1.EFP\LOCALS~1\Temp\s3h4.; 353. undefined
symbol "btemp"

Strange because no where in the program do my friend and I use the
identifier "btemp"... searching for btemp in the compiler manual finds:
"1. The BTEMP register is a memory location allocated by the compiler, but
which is treated like a register for code generation purposes."

Google for "undefined symbol btemp" finds:
<http://forum.htsoft.com/all/showflat.php?Cat=3D0&Number=3D1284&page=3D0&fp=
art=3D1&v
c=3D1>

In which the cryptic reply...

	Add the following bit of assembly:

	psect   temp,ovrld,class=3DBANK0,space=3D1
	global btemp
	btemp
	        ds      2
=09
	You could put #asm/#endasm around it and add it to the C file.

....provides us with a solution. Apparently, it needs to be at the end of th=
e
C file? Anyway, adding that code allows for a successful compile, and
destroys my confidence in the compiler...=20

I mean... really? Are you kidding? The compiler is using an identifier that
is isn't bothering to define space for? And one that (although we didn't)
has a name any one could /easily/ crash on?

Just for fairness, here is the program, so you can see how simple it is and
maybe find something in it that could cause an issue. Actually, if someone
could try compiling this on their PC I would appreciate it; just to see if
it does the same thing to you with out the #asm block at the end.=20

BTW: the offending line seems to be the=20
	for (;speed < MID_SPEED;speed++)=20
if you comment out that one line, it compiles without the asm block.=20

Also had to change=20

	return (int)(ADRESH << 8 | ADRESL);

(which seems more intuitive to me) into

	return (int)(ADRESH << 8 + ADRESL);

or the same error appears.

Here is the complete program (bugs, I'm sure, and all)

#include <htc.h>

__CONFIG (UNPROTECT
//	& BORDIS	//brown out reset disabled (default enabled)
	& MCLRDIS	//master clear reset on pin 3 disabled (default
enabled)
//	& PWRTEN	//power up timer enabled (default disabled)
	& WDTDIS	//watch dog timer disabled (default enabled)
	& INTIO 	//internal osc, GP4,5 are IO (default RCCLK)
	);
#define _XTAL_FREQ 4000000	//required for __delay_ms macro

#define AINbit 	0
volatile bit	AIN	@ (unsigned)&GPIO*8+AINbit;
#define STEPX	GPIO1
#define STEPY	GPIO2
#define STEPZ	GPIO4
#define DIR	GPIO5

void init() {
	TRISIO =3D 1<<AINbit;	//only the A2D is an input
	ANSEL =3D 1<<AINbit;	//the A2D pin is analog
	ADCS0 =3D ADCS1 =3D 1;	//RC clock
	}

typedef enum {cw=3D0,ccw=3D1} direction;
typedef enum {xaxis,yaxis,zaxis,aaxis} axis;

#define MID_SPEED ((1<<10)/2)
#define DEAD_BAND 32

void step(axis anaxis, direction adir) {
	DIR =3D 0;
	STEPX =3D STEPY =3D STEPZ =3D 0;
	DIR =3D adir;
	switch(anaxis) {
		case xaxis: STEPX =3D 1; break;
		case yaxis: STEPY =3D 1; break;
		case zaxis: STEPZ =3D 1; break;
		}
	}=09

int adc_read(unsigned char channel)
{
	ADCON0 =3D (channel << 3);//0xC1;		// enable ADC, RC osc.
	ADON =3D 1;
	VCFG =3D 0;	//Vcc is our reference
	ADFM =3D 1;	//0=3DTop 8 bits of result in ADRESH,1=3D10bits in
ADRESH/ADRESL
	GODONE =3D 1;
	while(GODONE)
		continue;	// wait for conversion complete
	return (int)(ADRESH << 8 + ADRESL);
}


void main() {
int speed;
direction dir;
	init();
	while(1) {
		speed =3D adc_read(0);
		speed =3D MID_SPEED-speed;
		dir =3D cw;
		if (speed<0) {dir =3D ccw; speed =3D -speed;};
		speed -=3D DEAD_BAND;
		if (speed < 0)=20
			continue;	//no movement in dead band
		for (;speed < MID_SPEED;speed++)=20
			__delay_ms(1);
		step(xaxis,dir);
//		step(yaxis,dir);
//		step(zaxis,dir);
		}=09
	}
=09
#asm
psect   temp,ovrld,class=3DBANK0,space=3D1
global btemp
btemp
        ds      2
#endasm

--
James Newton
1-970-462-7764=20


--=20
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