[Sdcc-user] Compile error, memory models

[Gudjon I. G. <gu...@gu...>]

Hi
   I was trying to compile a small program for an 8051 variant (a test version 
of my large one) and I get strange results:
#include "P89c66x.h"

void usleep(unsigned char j)
{
 // 1 = 3.12us
 unsigned char i;
 for ( i=0;i<=j;i++);
}

void main()
{
 while(1) {
   P1=0xFE;
   usleep(100);
   P1=0xFF;
   usleep(100);
 }
}

This program blinks pin P1_0. If I compile it with the small memory model, the 
usleep function works perfectly but it does not if I use large memory model. 
Then the sleeping time is independent of the input number.

The small sleep function is:
_usleep:
	ar2 = 0x02
	ar3 = 0x03
	ar4 = 0x04
	ar5 = 0x05
	ar6 = 0x06
	ar7 = 0x07
	ar0 = 0x00
	ar1 = 0x01
	mov	r2,dpl
;	test_array.c:9: for ( i=0;i<=j;i++);
	mov	r3,#0x00
00101$:
	clr	c
	mov	a,r2
	subb	a,r3
	jc	00105$
	inc	r3
	sjmp	00101$
00105$:
	ret


The large function is the following:
_usleep:
	ar2 = 0x02
	ar3 = 0x03
	ar4 = 0x04
	ar5 = 0x05
	ar6 = 0x06
	ar7 = 0x07
	ar0 = 0x00
	ar1 = 0x01
	mov	a,dpl
	mov	dptr,#_usleep_j_1_1
	movx	@dptr,a
;	test_array.c:9: for ( i=0;i<=j;i++);
	mov	dptr,#_usleep_j_1_1
	movx	a,@dptr
	mov	r2,a
	mov	r3,#0x00
00101$:
	clr	c
	mov	a,r2
	subb	a,r3
	jc	00105$
	inc	r3
	sjmp	00101$
00105$:
	ret

I don't see anything in the code that should not work.

Thanks 
Gudjon

Ps. I will read through the P89c66x.h file and then contribute it. Thanks for 
the nice software :)