Added timeDelta_t type

src/main/common/time.h

@@ -21,6 +21,8 @@
 
 #include "platform.h"
 
+// time difference, 32 bits always sufficient
+typedef int32_t timeDelta_t;
 // millisecond time
 typedef uint32_t timeMs_t ;
 // microsecond time
@@ -31,3 +33,5 @@ typedef uint64_t timeUs_t;
 typedef uint32_t timeUs_t;
 #define TIMEUS_MAX UINT32_MAX
 #endif
+
+static inline timeDelta_t cmpTimeUs(timeUs_t a, timeUs_t b) { return (timeDelta_t)(a - b); }

src/main/common/utils.h

@@ -73,7 +73,6 @@ http://resnet.uoregon.edu/~gurney_j/jmpc/bitwise.html
 
 static inline int16_t cmp16(uint16_t a, uint16_t b) { return a-b; }
 static inline int32_t cmp32(uint32_t a, uint32_t b) { return a-b; }
-static inline int32_t cmpTimeUs(timeUs_t a, timeUs_t b) { return a-b; }
 
 // using memcpy_fn will force memcpy function call, instead of inlining it. In most cases function call takes fewer instructions
 //  than inlined version (inlining is cheaper for very small moves < 8 bytes / 2 store instructions)

src/main/telemetry/hott.c

@@ -66,6 +66,7 @@
 #include "build/debug.h"
 
 #include "common/axis.h"
+#include "common/time.h"
 
 #include "drivers/system.h"
 #include "drivers/serial.h"