         return fast
     }
     
-    open static func readSlowChange(_ data: Data) -> SlowChangeData {
+    public static func readSlowChange(_ data: Data) -> SlowChangeData {
         let bytes = data.map { $0 }
-        let slow = SlowChangeData()
+        var slow = SlowChangeData()
         // Included Data:
         // FE State
         // Capabilities


/// :nodoc:
/// Based on ANT+ FE-C standard (::groan::)
open class JetBlackSerializer {
    
    open class SlowChangeData {
        var targetPower: UInt16?
        var userWeight: UInt16?
    }
    
    open class FastChangeData {
        var speed: UInt16?
        var cadence: UInt8?
        var power: UInt16?
    }
    
    open static func setTargetPower(_ watts: UInt16) -> [UInt8] {
        return [0xFF, 0xFF, UInt8(watts & 0xFF), UInt8(watts >> 8 & 0xFF), 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]
    }
    
    open static func setRiderWeight(_ weight: UInt16) -> [UInt8] {
        return [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, UInt8(weight & 0xFF), UInt8(weight >> 8 & 0xFF), 0xFF, 0xFF, 0xFF,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]
    }
    
    open static func setSimulationParameters(rollingResistance: Float, windResistance: Float, grade: Float, windSpeed: Float, draftingFactor: Float) -> [UInt8] {
        // need to convert params to ANT+ units
        return [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]
    }
    
    open static func readFastChange(_ data: Data) -> FastChangeData {
        let bytes = data.map { $0 }
        let fast = FastChangeData()
        // Included Data:
        // Elapsed Time
        // Distance Travelled

        return slow
    }
}

