diff --git a/apps/mstpcap/main.c b/apps/mstpcap/main.c
index 4da985a0..fc9e22e8 100644
--- a/apps/mstpcap/main.c
+++ b/apps/mstpcap/main.c
@@ -400,7 +400,7 @@ static void packet_statistics_clear(void)
 
 static uint32_t Timer_Silence(void *pArg)
 {
-    return mstimer_remaining(&Silence_Timer);
+    return mstimer_elapsed(&Silence_Timer);
 }
 
 static void Timer_Silence_Reset(void *pArg)
diff --git a/ports/bdk-atxx4-mstp/rs485.c b/ports/bdk-atxx4-mstp/rs485.c
index b0b372b7..9db99060 100644
--- a/ports/bdk-atxx4-mstp/rs485.c
+++ b/ports/bdk-atxx4-mstp/rs485.c
@@ -61,7 +61,7 @@ static struct mstimer Silence_Timer;
 bool rs485_silence_time_elapsed(
     uint16_t milliseconds)
 {
-    return (mstimer_remaining(&Silence_Timer) > milliseconds);
+    return (mstimer_elapsed(&Silence_Timer) > milliseconds);
 }
 
 /****************************************************************************
diff --git a/ports/linux/mstpsnap.c b/ports/linux/mstpsnap.c
index 58c300d3..942172ea 100644
--- a/ports/linux/mstpsnap.c
+++ b/ports/linux/mstpsnap.c
@@ -62,12 +62,14 @@ static volatile struct mstp_port_struct_t MSTP_Port;
 /* buffers needed by mstp port struct */
 static uint8_t RxBuffer[MAX_MPDU];
 static uint8_t TxBuffer[MAX_MPDU];
+static struct mstimer Silence_Timer;
+
 static uint32_t Timer_Silence(
     void *pArg)
 {
     uint32_t delta_time = 0;
 
-    delta_time = timer_milliseconds(TIMER_SILENCE);
+    delta_time = mstimer_elapsed(&Silence_Timer);
     if (delta_time > 0xFFFF) {
         delta_time = 0xFFFF;
     }
@@ -78,7 +80,7 @@ static uint32_t Timer_Silence(
 static void Timer_Silence_Reset(
     void *pArg)
 {
-    timer_reset(TIMER_SILENCE);
+    mstimer_set(&Silence_Timer, 0);
 }
 
 /* functions used by the MS/TP state machine to put or get data */
diff --git a/ports/stm32f10x/main.c b/ports/stm32f10x/main.c
index 56602329..fae8d3e0 100644
--- a/ports/stm32f10x/main.c
+++ b/ports/stm32f10x/main.c
@@ -76,7 +76,7 @@ void lse_init(
     while (1) {
         if (LSE_Delay < LSE_FAIL_FLAG) {
             mstimer_set(&Delay_Timer, 0);
-            while (mstimer_remaining(&Delay_Timer) <  500) {
+            while (mstimer_elapsed(&Delay_Timer) <  500) {
                 /* do nothing */
             }
             /* check whether LSE is ready, with 4 seconds timeout */
diff --git a/ports/stm32f10x/rs485.c b/ports/stm32f10x/rs485.c
index 1b055123..ce5bcdbc 100644
--- a/ports/stm32f10x/rs485.c
+++ b/ports/stm32f10x/rs485.c
@@ -72,7 +72,7 @@ void rs485_silence_reset(
 bool rs485_silence_elapsed(
     uint32_t interval)
 {
-    return (mstimer_remaining(&Silence_Timer) > interval);
+    return (mstimer_elapsed(&Silence_Timer) > interval);
 }
 
 /*************************************************************************
@@ -101,7 +101,7 @@ static uint16_t rs485_turnaround_time(
 bool rs485_turnaround_elapsed(
     void)
 {
-    return (mstimer_remaining(&Silence_Timer) > rs485_turnaround_time());
+    return (mstimer_elapsed(&Silence_Timer) > rs485_turnaround_time());
 }
 
 
diff --git a/ports/win32/dlmstp.c b/ports/win32/dlmstp.c
index 3dabef1e..6a8339dc 100644
--- a/ports/win32/dlmstp.c
+++ b/ports/win32/dlmstp.c
@@ -72,7 +72,7 @@ static struct mstimer Silence_Timer;
 static uint32_t Timer_Silence(
     void *pArg)
 {
-    return mstimer_remaining(&Silence_Timer);
+    return mstimer_elapsed(&Silence_Timer);
 }
 
 static void Timer_Silence_Reset(
diff --git a/ports/xplained/rs485.c b/ports/xplained/rs485.c
index b01d6630..d9120643 100644
--- a/ports/xplained/rs485.c
+++ b/ports/xplained/rs485.c
@@ -90,7 +90,7 @@ void rs485_silence_reset(void)
  */
 bool rs485_silence_elapsed(uint32_t interval)
 {
-    return (mstimer_remaining(&Silence_Timer) > interval);
+    return (mstimer_elapsed(&Silence_Timer) > interval);
 }
 
 /**
@@ -154,7 +154,7 @@ static uint16_t rs485_turnaround_time(void)
  */
 bool rs485_turnaround_elapsed(void)
 {
-    return (mstimer_remaining(&Silence_Timer) > rs485_turnaround_time());
+    return (mstimer_elapsed(&Silence_Timer) > rs485_turnaround_time());
 }
 
 /**
diff --git a/src/bacnet/basic/sys/mstimer.c b/src/bacnet/basic/sys/mstimer.c
index caee0af1..759ef248 100644
--- a/src/bacnet/basic/sys/mstimer.c
+++ b/src/bacnet/basic/sys/mstimer.c
@@ -106,6 +106,21 @@ unsigned long mstimer_remaining(struct mstimer *t)
     return t->start + t->interval - mstimer_now();
 }
 
+/**
+ * The time elapsed since the timer started
+ *
+ * This function returns the time elapsed.
+ *
+ * @param t A pointer to the timer
+ *
+ * @return The time elapsed since the last start of the timer
+ *
+ */
+unsigned long mstimer_elapsed(struct mstimer *t)
+{
+  return mstimer_now() - t->start;
+}
+
 /**
  * The value of the interval
  *
diff --git a/src/bacnet/basic/sys/mstimer.h b/src/bacnet/basic/sys/mstimer.h
index 180d8866..997e0134 100644
--- a/src/bacnet/basic/sys/mstimer.h
+++ b/src/bacnet/basic/sys/mstimer.h
@@ -59,6 +59,8 @@ int mstimer_expired(struct mstimer *t);
 BACNET_STACK_EXPORT
 unsigned long mstimer_remaining(struct mstimer *t);
 BACNET_STACK_EXPORT
+unsigned long mstimer_elapsed(struct mstimer *t);
+BACNET_STACK_EXPORT
 unsigned long mstimer_interval(struct mstimer *t);
 /* HAL implementation */
 BACNET_STACK_EXPORT