cc3200: Fix time.ticks_* functions.

cc3200/mods/modutime.c

@@ -32,6 +32,7 @@
 #include MICROPY_HAL_H
 #include "py/nlr.h"
 #include "py/obj.h"
+#include "py/smallint.h"
 #include "timeutils.h"
 #include "inc/hw_types.h"
 #include "inc/hw_ints.h"
@@ -152,7 +153,7 @@ STATIC mp_obj_t time_ticks_ms(void) {
     // We want to "cast" the 32 bit unsigned into a small-int.  This means
     // copying the MSB down 1 bit (extending the sign down), which is
     // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
-    return MP_OBJ_NEW_SMALL_INT(HAL_GetTick());
+    return MP_OBJ_NEW_SMALL_INT(HAL_GetTick() & MP_SMALL_INT_POSITIVE_MASK);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(time_ticks_ms_obj, time_ticks_ms);
 
@@ -160,7 +161,7 @@ STATIC mp_obj_t time_ticks_us(void) {
     // We want to "cast" the 32 bit unsigned into a small-int.  This means
     // copying the MSB down 1 bit (extending the sign down), which is
     // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
-    return MP_OBJ_NEW_SMALL_INT(sys_tick_get_microseconds());
+    return MP_OBJ_NEW_SMALL_INT(sys_tick_get_microseconds() & MP_SMALL_INT_POSITIVE_MASK);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(time_ticks_us_obj, time_ticks_us);
 
@@ -168,7 +169,7 @@ STATIC mp_obj_t time_ticks_cpu(void) {
     // We want to "cast" the 32 bit unsigned into a small-int.  This means
     // copying the MSB down 1 bit (extending the sign down), which is
     // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
-    return MP_OBJ_NEW_SMALL_INT(SysTickValueGet());
+    return MP_OBJ_NEW_SMALL_INT(SysTickValueGet() & MP_SMALL_INT_POSITIVE_MASK);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_0(time_ticks_cpu_obj, time_ticks_cpu);
 
@@ -178,7 +179,7 @@ STATIC mp_obj_t time_ticks_diff(mp_obj_t t0, mp_obj_t t1) {
     // equivalent to just using the MP_OBJ_NEW_SMALL_INT macro.
     uint32_t start = mp_obj_get_int(t0);
     uint32_t end = mp_obj_get_int(t1);
-    return MP_OBJ_NEW_SMALL_INT((end > start) ? (end - start) : (start - end));
+    return MP_OBJ_NEW_SMALL_INT((end - start) & MP_SMALL_INT_POSITIVE_MASK);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_2(time_ticks_diff_obj, time_ticks_diff);
 

tests/wipy/time.py

@@ -43,7 +43,6 @@ def spot_test(seconds, expected_time):
             return
     print("time.localtime(", seconds, ") returned", actual_time, "(pass)")
 
-
 test()
 spot_test(          0,  (2000,  1,  1,  0,  0,  0, 5,   1))
 spot_test(          1,  (2000,  1,  1,  0,  0,  1, 5,   1))
@@ -75,4 +74,4 @@ print(time.ticks_diff(t1, t2) < 2000)
 
 t1 = time.ticks_cpu()
 t2 = time.ticks_cpu()
-print(time.ticks_diff(t1, t2) < 16384)
+print(time.ticks_diff(t1, t2) >= 0)