Index: firmware/App/Controllers/SyringePump.c
===================================================================
diff -u -r61be28695d75fc3ba795be4f4f77e435dde1dd11 -r0edfb69c6bfe5bcac0dcf032939521be32aa50df
--- firmware/App/Controllers/SyringePump.c	(.../SyringePump.c)	(revision 61be28695d75fc3ba795be4f4f77e435dde1dd11)
+++ firmware/App/Controllers/SyringePump.c	(.../SyringePump.c)	(revision 0edfb69c6bfe5bcac0dcf032939521be32aa50df)
@@ -96,6 +96,8 @@
 #define SYRINGE_PUMP_RATE_CHECK_MARGIN                0.05                                  ///< 5 pct margin on commanded vs. measured rate check.
 #define SYRINGE_PUMP_VOLUME_CHECK_MARGIN              0.05                                  ///< 5 pct margin on commanded vs. encoder based volume check.
 
+#define SYRINGE_PUMP_ADC_READ_PERSISTENCE             ( 100 / TASK_PRIORITY_INTERVAL )      ///< Syringe pump ADC stale read alarm persistence time (100 ms).
+
 // Bit definitions for syringe pump control register
 #define SYRINGE_PUMP_CONTROL_SLEEP_OFF                0x40                                  ///< Syringe pump control register bit for sleep mode (active low).
 #define SYRINGE_PUMP_CONTROL_NOT_RESET                0x20                                  ///< Syringe pump control register bit for resetting stepper motor (active low).
@@ -201,6 +203,7 @@
 static F32  syringePumpDACVref;                                                 ///< DAC Vref setting for force sensor.
 
 static U08  lastSyringePumpADCReadCtr;                                          ///< Remember last ADC read counter to check new reads are fresh.
+static U32  syringePumpADCReadErrorCtr;                                         ///< Stale ADC read error persistence timer counter.
 
 static SYRINGE_PUMP_SELF_TEST_STATE_T syringePumpSelfTestState;                 ///< Current syringe pump self-test state.
 static U32 syringePumpSelfTestTimerCount;                                       ///< Timer counter for syringe pump self-test.
@@ -266,6 +269,7 @@
     syringePumpPrimeCompleted = FALSE;
 
     lastSyringePumpADCReadCtr = 0;
+    syringePumpADCReadErrorCtr = 0;
 
     // Reset request flags
     resetSyringePumpRequestFlags();
@@ -832,10 +836,17 @@
     {
 #ifndef USING_DEBUGGER
         // Check ADC read is fresh (takes FPGA a while to configure ADC so don't check until after init/POST mode
-        if ( ( getCurrentOperationMode() > MODE_INIT ) && ( lastSyringePumpADCReadCtr == adcReadCtr ) ) // TODO - add persistence or time window
+        if ( ( getCurrentOperationMode() > MODE_INIT ) && ( lastSyringePumpADCReadCtr == adcReadCtr ) )
         {
-            activateAlarmNoData( ALARM_ID_HD_SYRINGE_PUMP_ADC_ERROR );
+            if ( ++syringePumpADCReadErrorCtr > SYRINGE_PUMP_ADC_READ_PERSISTENCE )
+            {
+                activateAlarmNoData( ALARM_ID_HD_SYRINGE_PUMP_ADC_ERROR );
+            }
         }
+        else
+        {
+            syringePumpADCReadErrorCtr = 0;
+        }
 #endif
         lastSyringePumpADCReadCtr = adcReadCtr;