Jean-Paul PETILLON / Mbed OS test_usTimer

snippet to assess microsecond ticker reading function: uint32_t t = us_ticker_read();

Diff: mbed-os.lib

Revision:
0:677f08c93544
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os.lib	Fri Jan 24 17:52:52 2020 +0000
@@ -0,0 +1,1 @@
+https://github.com/armmbed/mbed-os/#2fd0c5cfbd83fce62da6308f9d64c0ab64e1f0d6