'Flex IRS Saw positioning

' Low Priority Interrupt on Timer3 overflow
' in Flex used to generate the stepping frequency for the motor
' here it also keeps track of the slide position: sawpos
Low_Prior_Interrupt:
Timer3_ISR:
    Context Save            ' Save the contents of WREG, STATUS, and BSR
    Clear PIR2bits_TMR3IF   ' Clear the Timer3 interrupt flag.
    Tim3 = Period           ' period wordt bepaald bij ontvangst van een note on
    Btg Mot_Klok            ' portA.5
    blueled = sensor1
    redled = sensor2
    If poweron = 1 Then     ' if power is off, the motor will not run.
      If mot_enable = 0 Then     ' this means the motor is running 
        If mot_dir = 0 Then      ' saw position monitoring in the interrupt.
                                 ' we are running cw, outwards with the saw 
            If sawpos > 0 Then Dec sawpos    ' we block off at zero
            If sensor1 = 1 Then              ' running cw and reaching the end
                    Set mot_enable           ' stop motor
                    Clear Sawpos             ' reset sawpos
                    Motspeed =1              ' reset speed
                    mot_dir = 1              ' inverse direction of rotation: set ccw
                    sollpos = hys_min        ' set soll position to away from the sensor
                    period = Freqs[Motspeed]
                    Timvals[2] = time + Dur5[Rampspeed]
                    Clear mot_enable         ' restart motor
                    'sollspeed = 64           ' to be tested value, set at note-on
            EndIf
        Else           
                                ' ccw running counterclockwize , bending the saw inwards
								' so increment motor step counter
            If sawpos < maxpos Then Inc sawpos  ' more efficient coding of the above.
            If sensor2 = 1 Then             ' end sensor reached
                Set mot_enable              ' stop motor
                maxpos = sawpos             ' store value for maxpos
                mot_dir = 0                 ' inverse direction of rotation : set cw
                sollpos = hys_max
                Motspeed = 1
                period = Freqs[Motspeed]
                Timvals[2] = time + Dur5[Rampspeed]
                Clear mot_enable            ' restart motor
                'sollspeed = 64
            EndIf
        EndIf
      EndIf
    EndIf
    Context Restore ' Restore the contents of WREG, STATUS, and BSR, then exit interrupt
'    Retfie         ' required?
'Return