package ClkDivider(mkClkDivider, ClkDivider(..)) where

interface (ClkDivider :: # -> *) hi =
  {
  reset :: Action
  ;isAdvancing :: Bool
  ;isHalfCycle :: Bool
  }

mkClkDivider :: Handle -> Module (ClkDivider hi)
mkClkDivider fileHandle = do
    counter <- mkReg(0 :: UInt (TLog hi))   
    let hi_value :: UInt (TLog hi) = (fromInteger $ valueOf hi)
    let half_hi_value :: UInt (TLog hi) = (fromInteger $ valueOf (TDiv hi 2))

    let val :: Real = (fromInteger $ valueOf hi)
    let msg = "Clock Div Period : " + (realToString val) + "\n"

    hPutStr fileHandle msg
    hPutStr fileHandle genModuleName

    addRules $
      rules
        {-# ASSERT fire when enabled #-}
        {-# ASSERT no implicit conditions #-}
        "tick" : when True ==> action
          $display (counter)
          counter := if (counter == hi_value)
                    then 0
                    else counter + 1
    
    return $
      interface ClkDivider
        reset :: Action
        reset = do
          counter := 0

        isAdvancing :: Bool
        isAdvancing = (counter == hi_value)
        isHalfCycle = (counter == half_hi_value)