Removed err4, display only stack when not empty on debug

src/devices/system.c

@@ -17,14 +17,14 @@ WITH REGARD TO THIS SOFTWARE.
 static const char *errors[] = {
 	"underflow",
 	"overflow",
-	"division by zero",
-	"Busy"
+	"division by zero"
 };
 
 static void
 system_print(Stack *s, char *name)
 {
 	Uint8 i;
+
 	fprintf(stderr, "<%s>", name);
 	for(i = 0; i < s->ptr; i++)
 		fprintf(stderr, " %02x", s->dat[i]);
@@ -36,7 +36,9 @@ system_print(Stack *s, char *name)
 void
 system_inspect(Uxn *u)
 {
+	if(u->wst->ptr)
 		system_print(u->wst, "wst");
+	if(u->rst->ptr)
 		system_print(u->rst, "rst");
 }
 

src/uxn.c

@@ -88,7 +88,7 @@ uxn_eval(Uxn *u, Uint16 pc)
 		case 0x1f: /* SFT */ POP8(a) POP(b) PUSH(src, b >> (a & 0x0f) << ((a & 0xf0) >> 4)) break;
 		}
 	}
-	return (u->wst->ptr || u->rst->ptr) ? uxn_halt(u, instr, 4, pc - 1) : 1;
+	return 1;
 err:
 	return uxn_halt(u, instr, errcode, pc - 1);
 }