diff --git a/cmd/main.go b/cmd/main.go
index be793d1..c1ca9fa 100755
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -1,4 +1,4 @@
-/* 
+/*
 MIT License
 
 Copyright (c) 2021 Justin Hammond
@@ -26,26 +26,55 @@ package main
 
 import (
 	"context"
-	"log"
+	"flag"
+	"fmt"
+	"os"
 	"time"
 
 	"github.com/Fishwaldo/go-dcdc200"
+	"github.com/Fishwaldo/go-dcdc200/internal/sim"
+	"github.com/Fishwaldo/go-logadapter/loggers/std"
 )
 
 
 func main() {
+	var simulation = flag.Bool("s", false, "Enable Simulation Mode")
+	var capture = flag.Bool("c", false, "Enable Packet Capture")
+	var help = flag.Bool("h", false, "Help")
+	flag.Parse()
+	if *help {
+		flag.PrintDefaults()
+		os.Exit(0)
+	}
+
 	dc := dcdcusb.DcDcUSB{}
-	dc.Init()
+	if *simulation {
+		if err := sim.SetCaptureFile("dcdcusb.txt"); err != nil {
+			fmt.Printf("Can't open Capture File dcdcusb.txt: %s\n", err)
+			os.Exit(-1)
+		}
+	}
+	dc.Init(stdlogger.DefaultLogger(), *simulation)
+
+	if *capture {
+		if *simulation {
+			fmt.Printf("Can't Enable Capture in Simulation Mode\n")
+			os.Exit(-1)
+		}
+		dc.SetCapture(*capture)
+	}
+
+	
 	if ok, err := dc.Scan(); !ok {
-		log.Fatalf("Scan Failed: %v", err)
-		return
+		fmt.Printf("Scan Failed: %v\n", err)
+		os.Exit(-1)
 	}
 	defer dc.Close()
-	for i := 0; i < 100; i++ {
+	for i := 0; i < 1000000; i++ {
 		ctx, cancel := context.WithTimeout(context.Background(), (1 * time.Second))
 		dc.GetAllParam(ctx)
 		cancel()
 		time.Sleep(1 * time.Second)
 	}
-	dc.Close()
+	os.Exit(0)
 }
diff --git a/dcdcusb.go b/dcdcusb.go
index eaaf6f1..3c49d53 100755
--- a/dcdcusb.go
+++ b/dcdcusb.go
@@ -1,4 +1,4 @@
-/* 
+/*
 MIT License
 
 Copyright (c) 2021 Justin Hammond
@@ -28,22 +28,29 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"sync"
+	"os"
 	"time"
 
+	"github.com/Fishwaldo/go-dcdc200/internal"
+	"github.com/Fishwaldo/go-dcdc200/internal/realusb"
+	"github.com/Fishwaldo/go-dcdc200/internal/sim"
 	"github.com/Fishwaldo/go-logadapter"
-	"github.com/Fishwaldo/go-logadapter/loggers/std"
-	"github.com/google/gousb"
 )
+
+type usbifI interface {
+	SetUSBDebug(level int)
+	Scan() (bool, error)
+	Close()
+	GetAllParam(ctx context.Context) ([]byte, int, error)
+}
+
 // Main Structure for the DCDCUSB Communications
 type DcDcUSB struct {
-	ctx      *gousb.Context
-	dev      *gousb.Device
-	intf     *gousb.Interface
-	done     func()
-	log      logadapter.Logger
-	initOnce sync.Once
-	connected bool
+	log         logadapter.Logger
+	connected   bool
+	captureData bool
+	simulation  bool
+	usbif       usbifI
 }
 
 // Represents the Settings for Off and Hardoff Delays when power is lost
@@ -51,190 +58,143 @@ type TimerConfigt struct {
 	// After Ignition Lost, this the time waiting till we toggle the Power Switch I/F
 	OffDelay time.Duration `json:"off_delay"`
 	// After the Power Switch I/F is toggled, this is the delay before we cut power
-	HardOff  time.Duration `json:"hard_off"`
+	HardOff time.Duration `json:"hard_off"`
 }
 
 // Status of Various Peripherals
 type Peripheralst struct {
 	// ??
-	OutSwVin   bool `json:"out_sw_vin"`
+	OutSwVin bool `json:"out_sw_vin"`
 	// ??
-	OutPsw     bool `json:"out_psw"`
+	OutPsw bool `json:"out_psw"`
 	// ??
 	OutStartOutput bool `json:"out_start_output"`
 	// Status of the Onboard Led
-	OutLed     bool `json:"out_led"`
-	// If the VOut is within range. 
+	OutLed bool `json:"out_led"`
+	// If the VOut is within range.
 	InVoutGood bool `json:"in_vout_good"`
 }
 
 // Overall Status of the DCDCUSB Power Supply
 type Params struct {
 	// What the Vout Setting is configured for
-	VoutSet      float32      `json:"vout_set"`
+	VoutSet float32 `json:"vout_set"`
 	// What Voltage the Config Jumpers are set for VOut
-	VoutConfig   float32      `json:"vout_config"`
+	VoutConfig float32 `json:"vout_config"`
 	// The Input Voltage
-	Vin          float32      `json:"vin"`
+	Vin float32 `json:"vin"`
 	// The Ignition Voltage
-	Vign         float32      `json:"vign"`
+	Vign float32 `json:"vign"`
 	// What the Actual VOut Voltage is
-	VoutActual   float32      `json:"vout_actual"`
+	VoutActual float32 `json:"vout_actual"`
 	// Status of Various Peripherals
-	Peripherals  Peripheralst `json:"peripherals"`
+	Peripherals Peripheralst `json:"peripherals"`
 	// ?? (Not Output Enabled?)
-	Output       bool         `json:"output"`
+	Output bool `json:"output"`
 	// ??
-	AuxVIn       bool         `json:"aux_v_in"`
+	AuxVIn bool `json:"aux_v_in"`
 	// Firmware Version?
-	Version      string       `json:"version"`
+	Version string `json:"version"`
 	// State of the Power Supply
-	State        DcdcStatet   `json:"state"`
+	State DcdcStatet `json:"state"`
 	// Config Registers (unknown)
-	CfgRegisters byte         `json:"cfg_registers"`
+	CfgRegisters byte `json:"cfg_registers"`
 	// Voltage Flags (Unknown)
-	VoltFlags    byte         `json:"volt_flags"`
+	VoltFlags byte `json:"volt_flags"`
 	// Timer Flags (Unknown)
-	TimerFlags   byte         `json:"timer_flags"`
+	TimerFlags byte `json:"timer_flags"`
 	// The configured countdown times for the Timer upon Power Loss
 	TimerConfig TimerConfigt `json:"timer_config"`
 	// Current Power Loss Debounce Timer
-	TimerWait     time.Duration `json:"timer_wait"`
+	TimerWait time.Duration `json:"timer_wait"`
 	// Current VOut Countdown Timer
-	TimerVOut     time.Duration `json:"timer_v_out"`
+	TimerVOut time.Duration `json:"timer_v_out"`
 	// Current VAux Countdown timer
-	TimerVAux     time.Duration `json:"timer_v_aux"`
+	TimerVAux time.Duration `json:"timer_v_aux"`
 	// Current Power Switch Toggle Count Down Timer
-	TimerPRWSW    time.Duration `json:"timer_prwsw"`
+	TimerPRWSW time.Duration `json:"timer_prwsw"`
 	// Current Soft Off Countdown Timer
-	TimerSoftOff  time.Duration `json:"timer_soft_off"`
+	TimerSoftOff time.Duration `json:"timer_soft_off"`
 	// Current Hard Off Countdown Timer
-	TimerHardOff  time.Duration `json:"timer_hard_off"`
-	// Current Script Position 
-	ScriptPointer byte          `json:"script_pointer"`
+	TimerHardOff time.Duration `json:"timer_hard_off"`
+	// Current Script Position
+	ScriptPointer byte `json:"script_pointer"`
 	// Current Operating Mode
-	Mode          DcdcModet     `json:"mode"`
-}
-// Initialize the DCDCUSB Communications. Should be first function called before any other methods are called
-func (dc *DcDcUSB) Init() {
-	dc.initOnce.Do(func() {
-		if dc.log == nil {
-			templogger := stdlogger.DefaultLogger()
-			templogger.Log.SetPrefix("DCDCUSB")
-			dc.log = templogger
-		}
-	})
-	dc.connected = false
-	dc.ctx = gousb.NewContext()
+	Mode DcdcModet `json:"mode"`
 }
 
-// Set a Custom Logger based on https://github.com/Fishwaldo/go-logadapter
-// If not set, then the Library will use the Std Library Logger
-func (dc *DcDcUSB) SetLogger(log logadapter.Logger) {
+// Initialize the DCDCUSB Communications. Should be first function called before any other methods are called
+// Pass a logadapter.Logger as the logger for this package and set simulation to true if you wish to reply a Captured Session instead of
+// live data.
+func (dc *DcDcUSB) Init(log logadapter.Logger, simulation bool) {
 	dc.log = log
+	dc.connected = false
+	dc.simulation = simulation
+	if !simulation {
+		dc.usbif = realusb.Init(dc.log)
+	} else {
+		dc.usbif = sim.Init(dc.log)
+	}
+}
+
+// Capture Data from the Power Supply and save it to dcdcusb.txt for replay via the simulator later
+func (dc *DcDcUSB) SetCapture(enabled bool) {
+	dc.captureData = true
 }
 
 // Set the debug level for the GoUSB Library
 func (dc *DcDcUSB) SetUSBDebug(level int) {
-	if dc.ctx != nil {
-		dc.ctx.Debug(level)
-	}
+	dc.usbif.SetUSBDebug(level)
 }
+
 // Returns if we are connected to the Power Supply
-func (dc *DcDcUSB) IsConnected() (bool) {
+func (dc *DcDcUSB) IsConnected() bool {
 	return dc.connected
 }
 
 // Scan for a DCDCUSB connection, returns true if found, or false (and optional error) if there
-// was a failure setting up communications with it. 
+// was a failure setting up communications with it.
 func (dc *DcDcUSB) Scan() (bool, error) {
 	var err error
-	dc.dev, err = dc.ctx.OpenDeviceWithVIDPID(dcdc200_vid, dcdc200_pid)
-	if err != nil {
-		dc.log.Warn("Could Not Open Device: %v", err)
-		dc.Close()
-		return false, err
-	}
-	if dc.dev == nil {
-		dc.log.Warn("Can't Find Device")
-		dc.Close()
-		return false, nil
-	}
-	err = dc.dev.SetAutoDetach(true)
-	if err != nil {
-		dc.log.Error("%s.SetAutoDetach(true): %v", dc.dev, err)
-	}
-
-	confignum, _ := dc.dev.ActiveConfigNum()
-	dc.log.Trace("Device Config: %s %d", dc.dev.String(), confignum)
-	//	desc, _ := dc.dev.GetStringDescriptor(1)
-	//	manu, _ := dc.dev.Manufacturer()
-	//	prod, _ := dc.dev.Product()
-	//	serial, _ := dc.dev.SerialNumber()
-	dc.intf, dc.done, err = dc.dev.DefaultInterface()
-	if err != nil {
-		dc.log.Error("%s.Interface(): %v", dc.dev, err)
-		dc.Close()
-		return false, err
-	}
-	dc.log.Trace("Interface: %s", dc.intf.String())
-	dc.log = dc.log.With("Device", dc.intf.String())
-	dc.connected = true
-	return true, nil
+	dc.connected, err = dc.usbif.Scan()
+	return dc.connected, err
 }
 func (dc *DcDcUSB) Close() {
-	if dc.intf != nil {
-		dc.done()
-		dc.intf.Close()
-	}
-	if dc.dev != nil {
-		dc.dev.Close()
-	}
-	if dc.ctx != nil {
-		dc.ctx.Close()
-	}
-	dc.connected = false;
+	dc.usbif.Close()
+	dc.connected = false
 }
 
-// Gets All current Params from the DCDCUSB power Supply. 
+// Gets All current Params from the DCDCUSB power Supply.
 // Set a Timeout/Deadline Context to cancel slow calls
 func (dc *DcDcUSB) GetAllParam(ctx context.Context) (Params, error) {
-	if dc.intf == nil {
-		dc.log.Warn("Interface Not Opened")
-		return Params{}, fmt.Errorf("Interface Not Opened")
-	}
-	outp, err := dc.intf.OutEndpoint(0x01)
+	recv, len, err := dc.usbif.GetAllParam(ctx)
 	if err != nil {
-		dc.log.Warn("Can't Get OutEndPoint: %s", err)
+		dc.log.Warn("GetAllParams Call Failed: %s", err)
 		return Params{}, err
 	}
-	//log.Printf("OutEndpoint: %v", outp)
-	var send = make([]byte, 24)
-	send[0] = cmdGetAllValues
-	//send = append(send, 0)
-	//log.Printf("About to Send %v", send)
-	len, err := outp.WriteContext(ctx, send)
-	if err != nil {
-		dc.log.Warn("Cant Send GetAllValues Command: %s (%v) - %d", err, send, len)
-		return Params{}, err
+	if len != 24 {
+		dc.log.Warn("Got Short Read From USB")
+		return Params{}, fmt.Errorf("got Short Read from USB")
 	}
-	//log.Printf("Sent %d Bytes", len)
-	inp, err := dc.intf.InEndpoint(0x81)
-	if err != nil {
-		dc.log.Warn("Can't Get OutPoint: %s", err)
-		return Params{}, err
-	}
-	//log.Printf("InEndpoint: %v", inp)
 
-	var recv = make([]byte, 24)
-	len, err = inp.ReadContext(ctx, recv)
-	if err != nil {
-		dc.log.Warn("Can't Read GetAllValues Command: %s", err)
-		return Params{}, err
+	if dc.captureData {
+		if dc.simulation {
+			dc.log.Warn("Running in Simulation Mode, Can't Capture")
+		} else {
+			f, err := os.OpenFile("dcdcusb.txt", os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+			if err != nil {
+				dc.log.Fatal("Can't open File for Capture: %s", err)
+			}
+
+			if _, err := f.Write(recv); err != nil {
+				dc.log.Fatal("Can't write Text to File: %s", err)
+			}
+			f.Close()
+		}
 	}
-	//log.Printf("Got %d Bytes", len)
+
 	dc.log.Trace("Got %v", recv)
-	params, err := dc.parseAllValues(recv, len)
+	params, err := dc.parseAllValues(recv)
 	return params, err
 }
 
@@ -245,9 +205,9 @@ func (dc *DcDcUSB) GetAllParam(ctx context.Context) (Params, error) {
 //                     2021/09/20 16:12:54 Got [130 133 8  76 0  44 25 133 205 251  1  0  0  0  0  0  0  0  0  0   0  0  0  167]
 //                     2021/09/20 16:12:56 Got [130 133 16 76 0  44 27 133 205 247  1  0  0  0  0  0  0  0  0  0   0  0 59  167]
 //                     2021/09/20 16:13:54 Got [130 133 16 76 0  44  9 133 205 247  1  0  0  0  0  0  0  0  0  0   0  0  0  167]
-func (dc *DcDcUSB) parseAllValues(buf []byte, len int) (Params, error) {
+func (dc *DcDcUSB) parseAllValues(buf []byte) (Params, error) {
 	switch buf[0] {
-	case cmdRecvAllValues:
+	case internal.CmdRecvAllValues:
 		param := Params{}
 		param.Mode = dc.modeToConst((buf[1] >> 6) & 0x7)
 		param.VoutConfig = dc.voutConfigtoFloat((buf[1] >> 2) & 0x07)
@@ -351,8 +311,8 @@ func (dc DcDcUSB) stateToConst(state byte) DcdcStatet {
 func (dc DcDcUSB) peripheralsState(state byte) Peripheralst {
 	p := Peripheralst{
 		InVoutGood:     ((state & 0x01) != 0),
-		OutLed:          ((state & 0x02) != 0),
-		OutPsw:          ((state & 0x04) != 0),
+		OutLed:         ((state & 0x02) != 0),
+		OutPsw:         ((state & 0x04) != 0),
 		OutStartOutput: ((state & 0x08) != 0),
 		OutSwVin:       ((state & 0x10) != 0),
 	}
diff --git a/dcdcusb_test.go b/dcdcusb_test.go
index 24291cf..407316c 100644
--- a/dcdcusb_test.go
+++ b/dcdcusb_test.go
@@ -27,13 +27,14 @@ package dcdcusb
 import (
 	"testing"
 	"time"
+	"github.com/Fishwaldo/go-logadapter/loggers/std"
 )
 
 func TestParseAllValues(t *testing.T) {
 	var test1 = []byte{130, 133, 7,  76, 75, 43, 27, 133, 215, 251,  1,  0,  0,  0,  0,  0,  0,  0,  0,  3,  68,  0,  0,  167}
 	dc := DcDcUSB{}
-	dc.Init()
-	result, err := dc.parseAllValues(test1, 24)
+	dc.Init(stdlogger.DefaultLogger(), false)
+	result, err := dc.parseAllValues(test1)
 	if err != nil {
 		t.Fatalf("Error Returned from parseAllValues: %v", err)
 	}
@@ -108,8 +109,8 @@ func TestParseAllValues(t *testing.T) {
 func TestParseAllValues2(t *testing.T) {
 	var test1 = []byte{130, 133, 8,  76, 0,  43, 27, 133, 205, 251,  1,  0,  0,  0,  0,  0,  0,  0,  0,  3, 127,  0,  0,  167}
 	dc := DcDcUSB{}
-	dc.Init()
-	result, err := dc.parseAllValues(test1, 24)
+	dc.Init(stdlogger.DefaultLogger(), false)
+	result, err := dc.parseAllValues(test1)
 	if err != nil {
 		t.Fatalf("Error Returned from parseAllValues: %v", err)
 	}
@@ -184,8 +185,8 @@ func TestParseAllValues2(t *testing.T) {
 func TestParseAllValues3(t *testing.T) {
 	var test1 = []byte{130, 133, 8,  76, 0,  44, 25, 133, 205, 251,  1,  0,  0,  0,  0,  0,  0,  0,  0,  0,   0,  0,  0,  167}
 	dc := DcDcUSB{}
-	dc.Init()
-	result, err := dc.parseAllValues(test1, 24)
+	dc.Init(stdlogger.DefaultLogger(), false)
+	result, err := dc.parseAllValues(test1)
 	if err != nil {
 		t.Fatalf("Error Returned from parseAllValues: %v", err)
 	}
@@ -259,8 +260,8 @@ func TestParseAllValues3(t *testing.T) {
 func TestParseAllValues4(t *testing.T) {
 	var test1 = []byte{130, 133, 16, 76, 0,  44, 27, 133, 205, 247,  1,  0,  0,  0,  0,  0,  0,  0,  0,  0,   0,  0, 59,  167}
 	dc := DcDcUSB{}
-	dc.Init()
-	result, err := dc.parseAllValues(test1, 24)
+	dc.Init(stdlogger.DefaultLogger(),false)
+	result, err := dc.parseAllValues(test1)
 	if err != nil {
 		t.Fatalf("Error Returned from parseAllValues: %v", err)
 	}
@@ -335,8 +336,8 @@ func TestParseAllValues4(t *testing.T) {
 func TestParseAllValues5(t *testing.T) {
 	var test1 = []byte{130, 133, 16, 76, 0,  44,  9, 133, 205, 247,  1,  0,  0,  0,  0,  0,  0,  0,  0,  0,   0,  0,  0,  167}
 	dc := DcDcUSB{}
-	dc.Init()
-	result, err := dc.parseAllValues(test1, 24)
+	dc.Init(stdlogger.DefaultLogger(), false)
+	result, err := dc.parseAllValues(test1)
 	if err != nil {
 		t.Fatalf("Error Returned from parseAllValues: %v", err)
 	}
diff --git a/dcdcusbexample_test.go b/dcdcusbexample_test.go
index efb9ccc..4afa1f0 100644
--- a/dcdcusbexample_test.go
+++ b/dcdcusbexample_test.go
@@ -6,11 +6,12 @@ import (
 	"time"
 
 	"github.com/Fishwaldo/go-dcdc200"
+	"github.com/Fishwaldo/go-logadapter/loggers/std"
 )
 
 func Example() {
 	dc := dcdcusb.DcDcUSB{}
-	dc.Init()
+	dc.Init(stdlogger.DefaultLogger(), false)
 	if ok, err := dc.Scan(); !ok {
 		log.Fatalf("Scan Failed: %v", err)
 		return
diff --git a/definitions.go b/definitions.go
index ea496c3..ee9ea54 100755
--- a/definitions.go
+++ b/definitions.go
@@ -24,89 +24,9 @@ SOFTWARE.
 
 package dcdcusb
 
-const (
-	dcdc200_vid = 0x04d8
-	dcdc200_pid = 0xd003
-)
 
-const (
-	statusOK    = 0x00
-	statusErase = 0x01
-	statusWrite = 0x02
-	statusRead  = 0x03
-	statusError = 0xFF
-)
 
-const (
-	cmdGetAllValues  = 0x81
-	cmdRecvAllValues = 0x82
-	cmdOut           = 0xB1
-	cmdIn            = 0xB2
-	cmdReadOut       = 0xA1
-	cmdReadIn        = 0xA2
-	cmdWriteOut      = 0xA3
-	cmdWriteIn       = 0xA4
-	cmdErase         = 0xA5
-)
 
-const (
-	msgInternal             = 0xFF
-	msgInternalDisconnected = 0x01
-)
-
-const (
-	cmdSetAuxWin         = 0x01
-	cmdSetPwSwitch       = 0x02
-	cmdSetOutput         = 0x03
-	cmdWriteVout         = 0x06
-	cmdReadVout          = 0x07
-	cmdIncVout           = 0x0C
-	cmdDecVout           = 0x0D
-	cmdLoadDefaults      = 0x0E
-	cmdScriptStart       = 0x10
-	cmdScriptStop        = 0x11
-	cmdSleep             = 0x12
-	cmdReadRegulatorStep = 0x13
-)
-
-const (
-	typeCodeMemory     = 0x00
-	typeEepromExternal = 0x01
-	typeEepromInternal = 0x02
-	typeCodeSplash     = 0x03
-)
-
-const (
-	flashReportEraseMemory = 0xF2 /* AddressLo : AddressHi : AddressUp (anywhere inside the 64 byte-block to be erased) */
-	flashReportReadMemory  = 0xF3 /* AddressLo : AddressHi : AddressUp : Data Length (1...32) */
-	flashReportWriteMemory = 0xF4 /* AddressLo : AddressHi : AddressUp : Data Length (1...32) : Data.... */
-	keyBdReportEraseMemory = 0xB2 /* same as F2 but in keyboard mode */
-	keybdReportReadMemory  = 0xB3 /* same as F3 but in keyboard mode */
-	keybdReportWriteMemory = 0xB4 /* same as F4 but in keyboard mode */
-	keybdReportMemory      = 0x41 /* response to b3,b4 */
-)
-
-const (
-	inReportExtEEData   = 0x31
-	outReportExtEERead  = 0xA1
-	outReportExtEEWrite = 0xA2
-	inReportIntEEData   = 0x32
-	outReportIntEERead  = 0xA3
-	outReportIntEEWrite = 0xA4
-)
-
-/* MEASUREMENT CONSTANTS */
-
-const (
-	ct_RW = 75
-	ct_R1 = 49900
-	ct_R2 = 1500
-	ct_RP = 10000
-)
-
-const check_char = 0xAA /* used for line/write check */
-
-const max_message_cnt = 64
 
 //go:generate stringer -type=DcdcModet
 type DcdcModet int
diff --git a/doc.go b/doc.go
index dfc1a25..a6010ac 100644
--- a/doc.go
+++ b/doc.go
@@ -30,5 +30,10 @@ it depends upon GoUSB which in turn depends upon the libusb C library, thus CGO
 
 Please see the GoUSB pages for hints on compiling for platforms other than linux
 
+Building
+
+Compile with the tag nogousb to disable compiling with USB Support. Then the only option available
+is a Simulator Mode that replays a previously captured session.
+
 */
 package dcdcusb
diff --git a/internal/definitions.go b/internal/definitions.go
new file mode 100644
index 0000000..c4d7aa3
--- /dev/null
+++ b/internal/definitions.go
@@ -0,0 +1,80 @@
+package internal
+
+const (
+	statusOK    = 0x00
+	statusErase = 0x01
+	statusWrite = 0x02
+	statusRead  = 0x03
+	statusError = 0xFF
+)
+
+const (
+	CmdGetAllValues  = 0x81
+	CmdRecvAllValues = 0x82
+	CmdOut           = 0xB1
+	CmdIn            = 0xB2
+	CmdReadOut       = 0xA1
+	CmdReadIn        = 0xA2
+	CmdWriteOut      = 0xA3
+	CmdWriteIn       = 0xA4
+	CmdErase         = 0xA5
+)
+
+const (
+	msgInternal             = 0xFF
+	msgInternalDisconnected = 0x01
+)
+
+const (
+	cmdSetAuxWin         = 0x01
+	cmdSetPwSwitch       = 0x02
+	cmdSetOutput         = 0x03
+	cmdWriteVout         = 0x06
+	cmdReadVout          = 0x07
+	cmdIncVout           = 0x0C
+	cmdDecVout           = 0x0D
+	cmdLoadDefaults      = 0x0E
+	cmdScriptStart       = 0x10
+	cmdScriptStop        = 0x11
+	cmdSleep             = 0x12
+	cmdReadRegulatorStep = 0x13
+)
+
+const (
+	typeCodeMemory     = 0x00
+	typeEepromExternal = 0x01
+	typeEepromInternal = 0x02
+	typeCodeSplash     = 0x03
+)
+
+const (
+	flashReportEraseMemory = 0xF2 /* AddressLo : AddressHi : AddressUp (anywhere inside the 64 byte-block to be erased) */
+	flashReportReadMemory  = 0xF3 /* AddressLo : AddressHi : AddressUp : Data Length (1...32) */
+	flashReportWriteMemory = 0xF4 /* AddressLo : AddressHi : AddressUp : Data Length (1...32) : Data.... */
+	keyBdReportEraseMemory = 0xB2 /* same as F2 but in keyboard mode */
+	keybdReportReadMemory  = 0xB3 /* same as F3 but in keyboard mode */
+	keybdReportWriteMemory = 0xB4 /* same as F4 but in keyboard mode */
+	keybdReportMemory      = 0x41 /* response to b3,b4 */
+)
+
+const (
+	inReportExtEEData   = 0x31
+	outReportExtEERead  = 0xA1
+	outReportExtEEWrite = 0xA2
+	inReportIntEEData   = 0x32
+	outReportIntEERead  = 0xA3
+	outReportIntEEWrite = 0xA4
+)
+
+/* MEASUREMENT CONSTANTS */
+
+const (
+	ct_RW = 75
+	ct_R1 = 49900
+	ct_R2 = 1500
+	ct_RP = 10000
+)
+
+const check_char = 0xAA /* used for line/write check */
+
+const max_message_cnt = 64
diff --git a/internal/realusb/realusb.go b/internal/realusb/realusb.go
new file mode 100644
index 0000000..7c33afc
--- /dev/null
+++ b/internal/realusb/realusb.go
@@ -0,0 +1,122 @@
+// +build !nogousb
+
+package realusb
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/Fishwaldo/go-dcdc200/internal"
+	"github.com/Fishwaldo/go-logadapter"
+	"github.com/google/gousb"
+)
+
+const (
+	dcdc200_vid = 0x04d8
+	dcdc200_pid = 0xd003
+)
+
+
+type UsbIF struct {
+	ctx      *gousb.Context
+	dev      *gousb.Device
+	intf     *gousb.Interface
+	done     func()
+	log logadapter.Logger
+}
+
+func Init(log logadapter.Logger) (*UsbIF) {
+	usbif := UsbIF{log: log, ctx: gousb.NewContext()}
+	return &usbif	
+}
+
+func (usbif *UsbIF) SetUSBDebug(level int) {
+	if usbif.ctx != nil {
+		usbif.ctx.Debug(level)
+	}
+}
+
+func (usbif *UsbIF) Scan() (bool, error) {
+	var err error
+	usbif.dev, err = usbif.ctx.OpenDeviceWithVIDPID(dcdc200_vid, dcdc200_pid)
+	if err != nil {
+		usbif.log.Warn("Could Not Open Device: %v", err)
+		usbif.Close()
+		return false, err
+	}
+	if usbif.dev == nil {
+		usbif.log.Warn("Can't Find Device")
+		usbif.Close()
+		return false, nil
+	}
+	err = usbif.dev.SetAutoDetach(true)
+	if err != nil {
+		usbif.log.Error("%s.SetAutoDetach(true): %v", usbif.dev, err)
+	}
+
+	confignum, _ := usbif.dev.ActiveConfigNum()
+	usbif.log.Trace("Device Config: %s %d", usbif.dev.String(), confignum)
+	//	desc, _ := dc.dev.GetStringDescriptor(1)
+	//	manu, _ := dc.dev.Manufacturer()
+	//	prod, _ := dc.dev.Product()
+	//	serial, _ := dc.dev.SerialNumber()
+	usbif.intf, usbif.done, err = usbif.dev.DefaultInterface()
+	if err != nil {
+		usbif.log.Error("%s.Interface(): %v", usbif.dev, err)
+		usbif.Close()
+		return false, err
+	}
+	usbif.log.Trace("Interface: %s", usbif.intf.String())
+	usbif.log = usbif.log.With("Device", usbif.intf.String())
+	return true, nil
+}
+
+func (usbif *UsbIF) Close() {
+	if usbif.intf != nil {
+		usbif.done()
+		usbif.intf.Close()
+	}
+	if usbif.dev != nil {
+		usbif.dev.Close()
+	}
+	if usbif.ctx != nil {
+		usbif.ctx.Close()
+	}
+}
+
+func (usbif *UsbIF) GetAllParam(ctx context.Context) ([]byte, int, error) {
+	if usbif.intf == nil {
+		usbif.log.Warn("Interface Not Opened")
+		return nil, 0, fmt.Errorf("interface Not Opened")
+	}
+	outp, err := usbif.intf.OutEndpoint(0x01)
+	if err != nil {
+		usbif.log.Warn("Can't Get OutEndPoint: %s", err)
+		return nil, 0, err
+	}
+	//log.Printf("OutEndpoint: %v", outp)
+	var send = make([]byte, 24)
+	send[0] = internal.CmdGetAllValues
+	//send = append(send, 0)
+	//log.Printf("About to Send %v", send)
+	len, err := outp.WriteContext(ctx, send)
+	if err != nil {
+		usbif.log.Warn("Cant Send GetAllValues Command: %s (%v) - %d", err, send, len)
+		return nil, 0, err
+	}
+	//log.Printf("Sent %d Bytes", len)
+	inp, err := usbif.intf.InEndpoint(0x81)
+	if err != nil {
+		usbif.log.Warn("Can't Get OutPoint: %s", err)
+		return nil, 0, err
+	}
+	//log.Printf("InEndpoint: %v", inp)
+
+	var recv = make([]byte, 24)
+	len, err = inp.ReadContext(ctx, recv)
+	if err != nil {
+		usbif.log.Warn("Can't Read GetAllValues Command: %s", err)
+		return nil, 0, err
+	}
+	return recv, len, nil
+}
\ No newline at end of file
diff --git a/internal/realusb/realusb_nogousb.go b/internal/realusb/realusb_nogousb.go
new file mode 100644
index 0000000..d0f1868
--- /dev/null
+++ b/internal/realusb/realusb_nogousb.go
@@ -0,0 +1,35 @@
+// +build nogousb
+
+package realusb
+
+import (
+	"context"
+	"fmt"
+	"github.com/Fishwaldo/go-logadapter"
+)
+
+type UsbIF struct {
+	log logadapter.Logger
+}
+
+func Init(log logadapter.Logger) (*UsbIF) {
+	usbif := UsbIF{log: log}
+	log.Panic("Not Compiled with USB Support!")
+	return &usbif	
+}
+
+func (usbif *UsbIF) SetUSBDebug(level int) {
+	usbif.log.Panic("Not Compiled with USB Support!")
+}
+
+func (usbif *UsbIF) Scan() (bool, error) {
+	usbif.log.Panic("Not Compiled with USB Support")
+	return false, fmt.Errorf("Not Compiled with USB Support")
+}
+func (usbif *UsbIF) Close() { 
+	usbif.log.Panic("Not Compiled with USB Support")
+}
+func (usbif *UsbIF) GetAllParam(ctx context.Context) ([]byte, int, error) {
+	usbif.log.Panic("Not Compiled with USB Support")
+	return nil, 0, fmt.Errorf("not compiled with USB Support")
+}
\ No newline at end of file
diff --git a/internal/sim/sim.go b/internal/sim/sim.go
new file mode 100644
index 0000000..0f361de
--- /dev/null
+++ b/internal/sim/sim.go
@@ -0,0 +1,82 @@
+package sim
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/Fishwaldo/go-logadapter"
+)
+
+type SimIF struct {
+	log  logadapter.Logger
+	file *os.File
+}
+
+var captureFile string
+
+func SetCaptureFile(name string) error {
+	file, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	captureFile = name
+	return nil
+}
+
+func Init(log logadapter.Logger) *SimIF {
+	usbif := SimIF{log: log}
+	usbif.log.Info("Enabling Simulation Replay")
+	var err error
+	usbif.file, err = os.Open(captureFile)
+	if err != nil {
+		usbif.log.Panic("cannot open USB Capture File %s: %s", captureFile, err)
+	}
+	return &usbif
+}
+
+func (usbif *SimIF) SetUSBDebug(level int) {
+}
+
+func (usbif *SimIF) Scan() (bool, error) {
+	if usbif.file != nil {
+		return true, nil
+	} else {
+		return false, fmt.Errorf("capture File Not Specified")
+	}
+}
+func (usbif *SimIF) Close() {
+	if usbif.file != nil {
+		usbif.file.Close()
+	}
+}
+func (usbif *SimIF) GetAllParam(ctx context.Context) ([]byte, int, error) {
+	if usbif.file == nil {
+		usbif.log.Panic("usb Capture File Not Opened")
+		return nil, 0, fmt.Errorf("usb Capture File Not Opened")
+	}
+	cap := make([]byte, 24)
+	var len int
+	var err error
+	len, err = usbif.file.Read(cap)
+	if err != nil {
+		if err == io.EOF {
+			usbif.file.Seek(0, 0)
+			_, err = usbif.file.Read(cap)
+			if err != nil {
+				usbif.log.Warn("Seek to start of file Failed: %s", err)
+				return nil, 0, fmt.Errorf("seek to Start of File Failed: %s", err)
+			}
+		} else {
+			usbif.log.Warn("Read From Capture File Returned Error: %s", err)
+			return nil, 0, fmt.Errorf("read from Capture FIle Returned %s", err)
+		}
+	}
+	if len != 24 {
+		usbif.log.Warn("Short Read from USB Capture File: %d", len)
+		return nil, 0, fmt.Errorf("short Read from USB Capture File: %d", len)
+	}
+	return cap, len, nil
+}
diff --git a/running.cap b/running.cap
new file mode 100644
index 0000000..60a817a
Binary files /dev/null and b/running.cap differ
diff --git a/shutdown.cap b/shutdown.cap
new file mode 100644
index 0000000..50d4f03
Binary files /dev/null and b/shutdown.cap differ