Pulsein problem

[Keith]

Im having a problem using the Pilsein command. Im' almost sure I have written the instruction an syntax correctly.

What is happening is the program runs properly without the "Pulsein Flow, FlowRate, mS" line but as soon as I un-comment it, compile and upload it, it freezes or halts the the loop.

the full program is attached below.

define Flow PORTC.3

Dim FlowRate as WORD

Main: ;----- start main*******
Do
; FlowRate = 0
; Count = Count + 1

  If ENCODER_SW = 0 Then
     Wait 400 mS
     Wait until ENCODER_SW = 1
     Locate 2,14
     LCDcursor FLASHON
     Wait 5 S                 ;Time to display Flasing Cursor
     Change_Temp
  End if

     Locate 0,0
       Print "VFD"
     Locate 0,9
       Print "|FAN"
     Locate 1,0
       Print "PUMP"
     Locate 1,9
       Print "|FLOW"
     Locate 1,17
       Print "L/M"
     Locate 2,0
       Print "THRESHOLD"
       Target_Temp
     Locate 3,0
       Print "COOLANT TEMP"
       Display_Temp

'' *Switch Pump and San On/Off ******

     If TempT >= value Then
        Set Pump On
        Locate 1,5
        Print "ON "
     End if

     If TempT <= (value-5) Then   ;0.°5C Switching Hysteresis Bandwidth
        Locate 1,5
        Print "OFF"
        Set Pump Off
     End if

     If TempT >= value + 5 Then
        Set Fan On
        Locate 0,15
        Print "ON "
     End if

     If TempT <= (value-10) Then   ;1.0°C Switching Hysteresis Bandwidth
        Locate 0,15
        Print "OFF"
        Set Fan Off
     End if

'' *Switch VFD and San On/Off ******

     If VFD = 0 Then
        Locate 0,5
        Print "ON "
     Else
        Locate 0,5
        Print "OFF"
     End if

'' *END Switch Pump and San On/Off *****

'' *Start Coolant Flow Rate *****
; Pulse:
Pulsein Flow, FlowRate, mS
FlowRate = FlowRate ;/5 ;Divide by 2
Locate 1,15
Print FlowRate
Locate 1,16
Print " "

  '' *******End Coolant Flow Rate ******************************

Loop

[Keith]

This has me really baffled ! it's working fine now - I don't understand...

Don't believe in Code Gremlins and fairy's

[Keith]

Now for today's aggravation.
The problem I'm having is reading the Pulsein signal output very occasionally throws 0 (zero) This can be seen in screenshot, Capture4 below.
I'm driving the input wit a 1kHz signal from a signal generator The input is preconditioned with two gates of a 74HC14 Hex Inverter Schmitt Trigger.

I need to be able to pick up the lack of coolant flow when the Pump and Spindle Motor VFD is on.
This is the code I have so far. I think I need something that ignores the missing pulses for a minute or so. The entire projet so far is attached below.

       Pulsein Flow, FlowRate, uS
      FlowRate = FlowRate  
      Locate 1,15
      Print FlowRate
    ;  Locate 1,16
    ;  Print " "

      If FlowRate = 0 Then
          Flowcount = Flowcount + 1
      End If

      If FlowRate > 0 Then
         Flowcount = 0
       End if

      If  Flowcount = 50 then
          Flow_error = 0
      End if

;    Loop

'' *End Coolant Flow Rate ********

    Do While VFD = 0 And Pump = On And Flow_error = 0
       Coolant_Error