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

If you need both (a regularly running interrupt and edge detection) it is probably easier to just do the former, and within the regularly scheduled interrupt you can check for edges, i.e.:

[code]

pulseDivider VAR Byte
edges VAR Byte
oldEdges VAR Byte

INTERRUPT 100_000

DEC pulseDivider
IF pulseDivider = 0 THEN
   pulseDivider = 10    
   ' do your regular pulse work. for example this would run 100000/10 or 10000x second
   pin = ~pin ' or whatever
ENDIF

' now check for edge detect changes 1000000x per second
edges = RB  ' or whereever pins are
IF edges.0 <> oldEdges.0  THEN ' it's different, must be an edge
   ' do some stuff
ENDIF
IF edges.1 <> oldEdges.1 THEN ' it's different, must be an edge
   IF edges.1 = 1 THEN ' high going edge, for example
   ' do some stuff
   ELSE                       ' low going edge
     ' do some stuff 
   ENDIF
ENDIF
oldEdges = edges

RETURNINT
[/code]

There are much more efficient ways to do this, but hopefully the above is clear enough that you get the basic idea. Others may have much cleverer suggestions as well.

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