anchor.diff:      // 60: 10  PS   5:  26  PS  13: 42  R-  21: 58  GC  29: 74  GC  37: 90  GC  45: 106 GC  53: 122 GC
       // 61: 12  SS   6:  28  SS  14: 44  R-  22: 60  GC  30: 76  GC  38: 92  GC  46: 108 GC  54: 124 GC
       // 62: 14  PS   7:  30  PS  15: 46  RC  23: 62  GC  31: 78  GC  39: 94  GC  47: 110 GC
  -    let ClockRasterCounter (mac, rasterX) =
  +    let ClockRasterCounter mac rasterX =
           if rasterLineCounter = config.RasterIncrement then
               rasterY <- nextRasterY.[rasterY]
               if rasterY = 0x0F8 then
  
positive.code:         (if mobMobCollisionIrqEnabled then 0x04 else 0x00) |||
          (if mobBackgroundCollisionIrqEnabled then 0x02 else 0x00) |||
          (if rasterIrqEnabled then 0x01 else 0x00)
      let SetInterruptRegister (value) =
          lightPenIrq <- (lightPenIrq && ((value &&& 0x08) = 0))
          mobMobCollisionIrq <- (mobMobCollisionIrq && ((value &&& 0x04) = 0))
          mobBackgroundCollisionIrq <- (mobBackgroundCollisionIrq && ((value &&& 0x02) = 0))
          rasterIrq <- (rasterIrq && ((value &&& 0x01) = 0))
      let SetInterruptEnable (value) =
          lightPenIrqEnabled <- (value &&& 0x08) <> 0
          mobMobCollisionIrqEnabled <- (value &&& 0x04) <> 0
          mobBackgroundCollisionIrq <- (value &&& 0x02) <> 0
  
negative.code: 
      // MxY (01, 03, 05, 07, 09, 0B, 0D, 0F)
      let mobY = Array.zeroCreate 8
      let GetMobY index =
          mobY.[index]
      let SetMobY index value =
          mobY.[index] <- value &&& 0xFF
  
      // RASTER/RST8 (11, 12) (high expects high bit in position 7 as if you wrote to the reg)
      let mutable rasterYCompareValue = 0
      let SetLowRasterYCompareValue value =
          rasterYCompareValue <- (rasterYCompareValue &&& 0x100) ||| value
      let mutable rasterY =
          config.RasterLinesPerFrame - 1
      let nextRasterY =
          Array.init config.RasterLinesPerFrame (fun y -> if y >= (config.RasterLinesPerFrame - 1) then 0 else (y + 1))
      let GetLowRasterY () =
          rasterY &&& 0x0FF
  
      // Control register 1 (11) (RST8/ECM/BMM/DEN/RSEL/YSCROLL)
      let mutable extraColorMode = false
  