stmhal - More systick cleanup. Fix HAL_Delay

1 files changed, 7 insertions, 5 deletions

diff --git a/stmhal/hal/src/stm32f4xx_hal.c b/stmhal/hal/src/stm32f4xx_hal.c
index 6df59f9f9..672422553 100644
--- a/stmhal/hal/src/stm32f4xx_hal.c
+++ b/stmhal/hal/src/stm32f4xx_hal.c
@@ -281,11 +281,13 @@ uint32_t HAL_GetTick(void)
   */

 void HAL_Delay(__IO uint32_t Delay)

 {

-  uint32_t timingdelay;

-  

-  timingdelay = HAL_GetTick() + Delay;

-  while(HAL_GetTick() < timingdelay)

-  {

+  uint32_t start = HAL_GetTick();

+

+  // Note that the following works (due to the magic of 2's complement numbers)

+  // even when Delay causes wraparound.

+

+  while (HAL_GetTick() - start <= Delay) {

+    __WFI();  // enter sleep mode, waiting for interrupt

   }

 }