diff --git a/armsrc/ticks.c b/armsrc/ticks.c
index 43555b21b..1510de490 100644
--- a/armsrc/ticks.c
+++ b/armsrc/ticks.c
@@ -185,6 +185,13 @@ uint32_t RAMFUNC GetCountSspClk(void) {
     return tmp_count;
 }
 
+uint32_t RAMFUNC GetCountSspClkDelta(uint32_t start) {
+    uint32_t stop = GetCountSspClk();
+    if ( stop >= start ) 
+        return stop - start;
+    return (UINT32_MAX - start) + stop;
+}
+
 //  -------------------------------------------------------------------------
 //  Timer for bitbanging, or LF stuff when you need a very precis timer
 //  1us = 1.5ticks
diff --git a/armsrc/ticks.h b/armsrc/ticks.h
index 089501c87..e036e018c 100644
--- a/armsrc/ticks.h
+++ b/armsrc/ticks.h
@@ -33,6 +33,7 @@ void SpinDelayCountUs(uint32_t us);
 void StartCountSspClk();
 void ResetSspClk(void);
 uint32_t RAMFUNC GetCountSspClk();
+uint32_t RAMFUNC GetCountSspClkDelta();
 
 void StartTicks(void);
 uint32_t GetTicks(void);