Using hardware capture

[rmteo]

Thanks. I converted it to SF.

Device = 18F4620       
Clock = 4

Dim Capture As PIR1.2   ' CCP1 capture flag
Dim CapIE As PIE1.2     ' CCP1 interrupt enable bit
Dim CapPriEn As IPR1.2  ' priority enable bit for CCP1 interrupt
Dim PriEnable As RCON.7 ' set to enable priority levels on interrupts

Dim T1 As Word          ' 1st capture value
Dim PW As Word          ' 2nd capture value & ultimately final pulse width
Dim CF As Boolean       ' indicates when last capture is ready
Dim CCP1 As Word Absolute $fbe   ' Location of CCPR1H:CCPR1L

Interrupt IntHigh()
   if CCP1CON.0=1 then  ' Capture from rising edge?
      t1 = ccp1         ' Move word to T1     
   else
      pw = ccp1         ' Move word to PW
      cf = true         ' Indicate last capture
   end if
   CCP1CON.0 = not CCP1CON.0  ' toggle between rising/falling edge captures
   capture = 0          ' Clear capture interrupt flag bit
End Interrupt

Sub Init()
   CCP1CON = %00000101  ' Capture mode, capture on rising edge
   T1CON = 0            ' TMR1 prescale=1, clock=Fosc/4, TMR1=off
   TMR1H = 0            ' Clear high byte of TMR1 counter
   TMR1L = 0            ' Clear low byte
   PriEnable = 1        ' enable priority levels on interrupts
   Capture = 0          ' clear capture flag bit
   CapPriEn = 1         ' set CCP1 int to high priority
   CapIE = 1            ' enable the CCP1 capture interrupt
   INTCON = %11000000   ' global + peripheral ints enabled
   T1CON.0 = 1          ' Turn TMR1 on here
End Sub

' Main Program Entry
Init                    ' Initialization
TRISC.2 = 1             ' CCP1 input pin (Capture input on 18F4620)
Enable(IntHigh)         ' Enable Interrupts

While true
   ' do other stuff here as required
   If CF Then           ' figure out & print result only after last capture
      PW = PW-T1        ' High pulse width = PW-T1
      CF = false        ' Clear flag bit
      ' Send Out Data
   EndIf
Wend