Merge pull request #5841 from ARMmbed/release-candidate

Release candidate for mbed-os-5.7.3

Author: 0xc0170

README.md

@@ -28,7 +28,7 @@ The [release notes](https://os.mbed.com/releases) detail the current release. Yo
 
 ## Getting started for developers
 
-We have a [developer webiste](https://os.mbed.com) for asking questions, engaging with others, finding information on boards and components, using an online IDE and compiler, reading the documentation and learning about what's new and what's coming next in Mbed OS.
+We have a [developer website](https://os.mbed.com) for asking questions, engaging with others, finding information on boards and components, using an online IDE and compiler, reading the documentation and learning about what's new and what's coming next in Mbed OS.
 
 ## Getting started for contributors
 

TESTS/mbed_drivers/lp_timer/main.cpp

@@ -51,13 +51,17 @@ extern uint32_t SystemCoreClock;
  *   For K64F          DELTA = (80000 / 120000000) * 1000000 = 666[us]
  *   For NUCLEO_F070RB DELTA = (80000 /  48000000) * 1000000 = 1666[us]
  *   For NRF51_DK      DELTA = (80000 /  16000000) * 1000000 = 5000[us]
+ *
+ * As low power timer cannot be too much accurate, this DELTA should not be more precise than 500us,
+ * which corresponds to a maximum CPU clock around 130MHz
  */
 #define US_PER_SEC       1000000
 #define US_PER_MSEC      1000
 #define TOLERANCE_FACTOR 80000.0f
 #define US_FACTOR        1000000.0f
+#define CLOCK_MAX        130000000
 
-static const int delta_sys_clk_us = ((int) (TOLERANCE_FACTOR / (float) SystemCoreClock * US_FACTOR));
+static const int delta_sys_clk_us = (SystemCoreClock < CLOCK_MAX? ((int) (TOLERANCE_FACTOR / (float) SystemCoreClock * US_FACTOR)):((int) (TOLERANCE_FACTOR / (float) CLOCK_MAX * US_FACTOR)));
 
 /* When test performs time measurement using Timer in sequence, then measurement error accumulates
  * in the successive attempts. */