In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Zoot wrote:

Why not use a simple RTCC interrupt that's at least 4x faster than your pulses, and count them there? e.g.

[code]
samplePin PIN RB.0 INPUT

sampleFrame VAR Word
sampleCount VAR Word
sampleCaptured VAR Word
sampleState VAR Byte

INTERRUPT 400_000 ' will count pulses up to 100khz
   sampleState.0 = samplePin ' capture pin right now
   IF sampleState.0 = 1 THEN ' this state was 1
         IF sampleState.1 = 0 THEN ' previous state 0, must be rising edge
             INC sampleCount
         ENDIF
   ENDIF
   sampleState = sampleState << 1 ' save current state as previous

   INC sampleFrame
   IF sampleFrame >= 4000 THEN ' capture every 10ms
       sampleCaptured = sampleCount
       sampleCount = 0
       sampleFrame = 0
   ENDIF

   RETURNINT

Start:


Main:

   'debug sampleCaptured

   GOTO Main   

[/code]

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