diff --git a/src/machine/machine_atsamd21_usb.go b/src/machine/machine_atsamd21_usb.go
index 51f276c0..f47b1ee3 100644
--- a/src/machine/machine_atsamd21_usb.go
+++ b/src/machine/machine_atsamd21_usb.go
@@ -275,15 +275,15 @@ func handleUSBIRQ(intr interrupt.Interrupt) {
 		usbEndpointDescriptors[0].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 
 		ok := false
-		if (setup.bmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
+		if (setup.BmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
 			// Standard Requests
 			ok = handleStandardSetup(setup)
 		} else {
 			// Class Interface Requests
-			if setup.wIndex == usb_CDC_ACM_INTERFACE {
+			if setup.WIndex == usb_CDC_ACM_INTERFACE {
 				ok = cdcSetup(setup)
-			} else if setup.bmRequestType == usb_SET_REPORT_TYPE && setup.bRequest == usb_SET_IDLE {
-				sendZlp()
+			} else if setup.BmRequestType == usb_SET_REPORT_TYPE && setup.BRequest == usb_SET_IDLE {
+				SendZlp()
 				ok = true
 			}
 		}
@@ -411,37 +411,37 @@ func initEndpoint(ep, config uint32) {
 	}
 }
 
-func handleStandardSetup(setup usbSetup) bool {
-	switch setup.bRequest {
+func handleStandardSetup(setup USBSetup) bool {
+	switch setup.BRequest {
 	case usb_GET_STATUS:
 		buf := []byte{0, 0}
 
-		if setup.bmRequestType != 0 { // endpoint
+		if setup.BmRequestType != 0 { // endpoint
 			// TODO: actually check if the endpoint in question is currently halted
 			if isEndpointHalt {
 				buf[0] = 1
 			}
 		}
 
-		sendUSBPacket(0, buf, setup.wLength)
+		sendUSBPacket(0, buf, setup.WLength)
 		return true
 
 	case usb_CLEAR_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = false
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = false
 		}
-		sendZlp()
+		SendZlp()
 		return true
 
 	case usb_SET_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = true
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = true
 		}
-		sendZlp()
+		SendZlp()
 		return true
 
 	case usb_SET_ADDRESS:
@@ -465,7 +465,7 @@ func handleStandardSetup(setup usbSetup) bool {
 		}
 
 		// last, set the device address to that requested by host
-		sam.USB_DEVICE.DADD.SetBits(setup.wValueL)
+		sam.USB_DEVICE.DADD.SetBits(setup.WValueL)
 		sam.USB_DEVICE.DADD.SetBits(sam.USB_DEVICE_DADD_ADDEN)
 
 		return true
@@ -479,16 +479,16 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_CONFIGURATION:
 		buff := []byte{usbConfiguration}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_CONFIGURATION:
-		if setup.bmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
+		if setup.BmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
 			for i := 1; i < len(endPoints); i++ {
 				initEndpoint(uint32(i), endPoints[i])
 			}
 
-			usbConfiguration = setup.wValueL
+			usbConfiguration = setup.WValueL
 
 			// Enable interrupt for CDC control messages from host (OUT packet)
 			setEPINTENSET(usb_CDC_ENDPOINT_ACM, sam.USB_DEVICE_EPINTENSET_TRCPT1)
@@ -501,7 +501,7 @@ func handleStandardSetup(setup usbSetup) bool {
 				setEPINTENSET(usb_HID_ENDPOINT_IN, sam.USB_DEVICE_EPINTENSET_TRCPT1)
 			}
 
-			sendZlp()
+			SendZlp()
 			return true
 		} else {
 			return false
@@ -509,13 +509,13 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_INTERFACE:
 		buff := []byte{usbSetInterface}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_INTERFACE:
-		usbSetInterface = setup.wValueL
+		usbSetInterface = setup.WValueL
 
-		sendZlp()
+		SendZlp()
 		return true
 
 	default:
@@ -523,9 +523,9 @@ func handleStandardSetup(setup usbSetup) bool {
 	}
 }
 
-func cdcSetup(setup usbSetup) bool {
-	if setup.bmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_GET_LINE_CODING {
+func cdcSetup(setup USBSetup) bool {
+	if setup.BmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_GET_LINE_CODING {
 			var b [cdcLineInfoSize]byte
 			b[0] = byte(usbLineInfo.dwDTERate)
 			b[1] = byte(usbLineInfo.dwDTERate >> 8)
@@ -535,13 +535,13 @@ func cdcSetup(setup usbSetup) bool {
 			b[5] = byte(usbLineInfo.bParityType)
 			b[6] = byte(usbLineInfo.bDataBits)
 
-			sendUSBPacket(0, b[:], setup.wLength)
+			sendUSBPacket(0, b[:], setup.WLength)
 			return true
 		}
 	}
 
-	if setup.bmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_SET_LINE_CODING {
+	if setup.BmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_SET_LINE_CODING {
 			b, err := receiveUSBControlPacket()
 			if err != nil {
 				return false
@@ -553,25 +553,25 @@ func cdcSetup(setup usbSetup) bool {
 			usbLineInfo.bDataBits = b[6]
 		}
 
-		if setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
-			usbLineInfo.lineState = setup.wValueL
+		if setup.BRequest == usb_CDC_SET_CONTROL_LINE_STATE {
+			usbLineInfo.lineState = setup.WValueL
 		}
 
-		if setup.bRequest == usb_CDC_SET_LINE_CODING || setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
+		if setup.BRequest == usb_CDC_SET_LINE_CODING || setup.BRequest == usb_CDC_SET_CONTROL_LINE_STATE {
 			// auto-reset into the bootloader
 			if usbLineInfo.dwDTERate == 1200 && usbLineInfo.lineState&usb_CDC_LINESTATE_DTR == 0 {
 				EnterBootloader()
 			} else {
 				// TODO: cancel any reset
 			}
-			sendZlp()
+			SendZlp()
 		}
 
-		if setup.bRequest == usb_CDC_SEND_BREAK {
+		if setup.BRequest == usb_CDC_SEND_BREAK {
 			// TODO: something with this value?
 			// breakValue = ((uint16_t)setup.wValueH << 8) | setup.wValueL;
 			// return false;
-			sendZlp()
+			SendZlp()
 		}
 		return true
 	}
@@ -678,7 +678,7 @@ func handleEndpoint(ep uint32) {
 	setEPSTATUSCLR(ep, sam.USB_DEVICE_EPSTATUSCLR_BK0RDY)
 }
 
-func sendZlp() {
+func SendZlp() {
 	usbEndpointDescriptors[0].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 }
 
diff --git a/src/machine/machine_atsamd51_usb.go b/src/machine/machine_atsamd51_usb.go
index f0f7e114..d49a68b4 100644
--- a/src/machine/machine_atsamd51_usb.go
+++ b/src/machine/machine_atsamd51_usb.go
@@ -279,15 +279,15 @@ func handleUSBIRQ(interrupt.Interrupt) {
 		usbEndpointDescriptors[0].DeviceDescBank[0].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 
 		ok := false
-		if (setup.bmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
+		if (setup.BmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
 			// Standard Requests
 			ok = handleStandardSetup(setup)
 		} else {
 			// Class Interface Requests
-			if setup.wIndex == usb_CDC_ACM_INTERFACE {
+			if setup.WIndex == usb_CDC_ACM_INTERFACE {
 				ok = cdcSetup(setup)
-			} else if setup.bmRequestType == usb_SET_REPORT_TYPE && setup.bRequest == usb_SET_IDLE {
-				sendZlp()
+			} else if setup.BmRequestType == usb_SET_REPORT_TYPE && setup.BRequest == usb_SET_IDLE {
+				SendZlp()
 				ok = true
 			}
 		}
@@ -415,37 +415,37 @@ func initEndpoint(ep, config uint32) {
 	}
 }
 
-func handleStandardSetup(setup usbSetup) bool {
-	switch setup.bRequest {
+func handleStandardSetup(setup USBSetup) bool {
+	switch setup.BRequest {
 	case usb_GET_STATUS:
 		buf := []byte{0, 0}
 
-		if setup.bmRequestType != 0 { // endpoint
+		if setup.BmRequestType != 0 { // endpoint
 			// TODO: actually check if the endpoint in question is currently halted
 			if isEndpointHalt {
 				buf[0] = 1
 			}
 		}
 
-		sendUSBPacket(0, buf, setup.wLength)
+		sendUSBPacket(0, buf, setup.WLength)
 		return true
 
 	case usb_CLEAR_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = false
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = false
 		}
-		sendZlp()
+		SendZlp()
 		return true
 
 	case usb_SET_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = true
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = true
 		}
-		sendZlp()
+		SendZlp()
 		return true
 
 	case usb_SET_ADDRESS:
@@ -469,7 +469,7 @@ func handleStandardSetup(setup usbSetup) bool {
 		}
 
 		// last, set the device address to that requested by host
-		sam.USB_DEVICE.DADD.SetBits(setup.wValueL)
+		sam.USB_DEVICE.DADD.SetBits(setup.WValueL)
 		sam.USB_DEVICE.DADD.SetBits(sam.USB_DEVICE_DADD_ADDEN)
 
 		return true
@@ -483,16 +483,16 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_CONFIGURATION:
 		buff := []byte{usbConfiguration}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_CONFIGURATION:
-		if setup.bmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
+		if setup.BmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
 			for i := 1; i < len(endPoints); i++ {
 				initEndpoint(uint32(i), endPoints[i])
 			}
 
-			usbConfiguration = setup.wValueL
+			usbConfiguration = setup.WValueL
 
 			// Enable interrupt for CDC control messages from host (OUT packet)
 			setEPINTENSET(usb_CDC_ENDPOINT_ACM, sam.USB_DEVICE_ENDPOINT_EPINTENSET_TRCPT1)
@@ -505,7 +505,7 @@ func handleStandardSetup(setup usbSetup) bool {
 				setEPINTENSET(usb_HID_ENDPOINT_IN, sam.USB_DEVICE_ENDPOINT_EPINTENSET_TRCPT1)
 			}
 
-			sendZlp()
+			SendZlp()
 			return true
 		} else {
 			return false
@@ -513,13 +513,13 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_INTERFACE:
 		buff := []byte{usbSetInterface}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_INTERFACE:
-		usbSetInterface = setup.wValueL
+		usbSetInterface = setup.WValueL
 
-		sendZlp()
+		SendZlp()
 		return true
 
 	default:
@@ -527,9 +527,9 @@ func handleStandardSetup(setup usbSetup) bool {
 	}
 }
 
-func cdcSetup(setup usbSetup) bool {
-	if setup.bmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_GET_LINE_CODING {
+func cdcSetup(setup USBSetup) bool {
+	if setup.BmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_GET_LINE_CODING {
 			var b [cdcLineInfoSize]byte
 			b[0] = byte(usbLineInfo.dwDTERate)
 			b[1] = byte(usbLineInfo.dwDTERate >> 8)
@@ -539,13 +539,13 @@ func cdcSetup(setup usbSetup) bool {
 			b[5] = byte(usbLineInfo.bParityType)
 			b[6] = byte(usbLineInfo.bDataBits)
 
-			sendUSBPacket(0, b[:], setup.wLength)
+			sendUSBPacket(0, b[:], setup.WLength)
 			return true
 		}
 	}
 
-	if setup.bmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_SET_LINE_CODING {
+	if setup.BmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_SET_LINE_CODING {
 			b, err := receiveUSBControlPacket()
 			if err != nil {
 				return false
@@ -557,25 +557,25 @@ func cdcSetup(setup usbSetup) bool {
 			usbLineInfo.bDataBits = b[6]
 		}
 
-		if setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
-			usbLineInfo.lineState = setup.wValueL
+		if setup.BRequest == usb_CDC_SET_CONTROL_LINE_STATE {
+			usbLineInfo.lineState = setup.WValueL
 		}
 
-		if setup.bRequest == usb_CDC_SET_LINE_CODING || setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
+		if setup.BRequest == usb_CDC_SET_LINE_CODING || setup.BRequest == usb_CDC_SET_CONTROL_LINE_STATE {
 			// auto-reset into the bootloader
 			if usbLineInfo.dwDTERate == 1200 && usbLineInfo.lineState&usb_CDC_LINESTATE_DTR == 0 {
 				EnterBootloader()
 			} else {
 				// TODO: cancel any reset
 			}
-			sendZlp()
+			SendZlp()
 		}
 
-		if setup.bRequest == usb_CDC_SEND_BREAK {
+		if setup.BRequest == usb_CDC_SEND_BREAK {
 			// TODO: something with this value?
 			// breakValue = ((uint16_t)setup.wValueH << 8) | setup.wValueL;
 			// return false;
-			sendZlp()
+			SendZlp()
 		}
 		return true
 	}
@@ -683,7 +683,7 @@ func handleEndpoint(ep uint32) {
 	setEPSTATUSCLR(ep, sam.USB_DEVICE_ENDPOINT_EPSTATUSCLR_BK0RDY)
 }
 
-func sendZlp() {
+func SendZlp() {
 	usbEndpointDescriptors[0].DeviceDescBank[1].PCKSIZE.ClearBits(usb_DEVICE_PCKSIZE_BYTE_COUNT_Mask << usb_DEVICE_PCKSIZE_BYTE_COUNT_Pos)
 }
 
diff --git a/src/machine/machine_nrf52840_usb.go b/src/machine/machine_nrf52840_usb.go
index 663f9e22..a01285f3 100644
--- a/src/machine/machine_nrf52840_usb.go
+++ b/src/machine/machine_nrf52840_usb.go
@@ -242,14 +242,14 @@ func handleUSBIRQ(interrupt.Interrupt) {
 		setup := parseUSBSetupRegisters()
 
 		ok := false
-		if (setup.bmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
+		if (setup.BmRequestType & usb_REQUEST_TYPE) == usb_REQUEST_STANDARD {
 			// Standard Requests
 			ok = handleStandardSetup(setup)
 		} else {
-			if setup.wIndex == usb_CDC_ACM_INTERFACE {
+			if setup.WIndex == usb_CDC_ACM_INTERFACE {
 				ok = cdcSetup(setup)
-			} else if setup.bmRequestType == usb_SET_REPORT_TYPE && setup.bRequest == usb_SET_IDLE {
-				sendZlp()
+			} else if setup.BmRequestType == usb_SET_REPORT_TYPE && setup.BRequest == usb_SET_IDLE {
+				SendZlp()
 				ok = true
 			}
 		}
@@ -323,14 +323,14 @@ func parseUSBLineInfo(b []byte) {
 	usbLineInfo.bDataBits = b[6]
 }
 
-func parseUSBSetupRegisters() usbSetup {
-	return usbSetup{
-		bmRequestType: uint8(nrf.USBD.BMREQUESTTYPE.Get()),
-		bRequest:      uint8(nrf.USBD.BREQUEST.Get()),
-		wValueL:       uint8(nrf.USBD.WVALUEL.Get()),
-		wValueH:       uint8(nrf.USBD.WVALUEH.Get()),
-		wIndex:        uint16((nrf.USBD.WINDEXH.Get() << 8) | nrf.USBD.WINDEXL.Get()),
-		wLength:       uint16(((nrf.USBD.WLENGTHH.Get() & 0xff) << 8) | (nrf.USBD.WLENGTHL.Get() & 0xff)),
+func parseUSBSetupRegisters() USBSetup {
+	return USBSetup{
+		BmRequestType: uint8(nrf.USBD.BMREQUESTTYPE.Get()),
+		BRequest:      uint8(nrf.USBD.BREQUEST.Get()),
+		WValueL:       uint8(nrf.USBD.WVALUEL.Get()),
+		WValueH:       uint8(nrf.USBD.WVALUEH.Get()),
+		WIndex:        uint16((nrf.USBD.WINDEXH.Get() << 8) | nrf.USBD.WINDEXL.Get()),
+		WLength:       uint16(((nrf.USBD.WLENGTHH.Get() & 0xff) << 8) | (nrf.USBD.WLENGTHL.Get() & 0xff)),
 	}
 }
 
@@ -360,33 +360,33 @@ func initEndpoint(ep, config uint32) {
 	}
 }
 
-func handleStandardSetup(setup usbSetup) bool {
-	switch setup.bRequest {
+func handleStandardSetup(setup USBSetup) bool {
+	switch setup.BRequest {
 	case usb_GET_STATUS:
 		buf := []byte{0, 0}
 
-		if setup.bmRequestType != 0 { // endpoint
+		if setup.BmRequestType != 0 { // endpoint
 			if isEndpointHalt {
 				buf[0] = 1
 			}
 		}
 
-		sendUSBPacket(0, buf, setup.wLength)
+		sendUSBPacket(0, buf, setup.WLength)
 		return true
 
 	case usb_CLEAR_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = false
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = false
 		}
 		nrf.USBD.TASKS_EP0STATUS.Set(1)
 		return true
 
 	case usb_SET_FEATURE:
-		if setup.wValueL == 1 { // DEVICEREMOTEWAKEUP
+		if setup.WValueL == 1 { // DEVICEREMOTEWAKEUP
 			isRemoteWakeUpEnabled = true
-		} else if setup.wValueL == 0 { // ENDPOINTHALT
+		} else if setup.WValueL == 0 { // ENDPOINTHALT
 			isEndpointHalt = true
 		}
 		nrf.USBD.TASKS_EP0STATUS.Set(1)
@@ -405,11 +405,11 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_CONFIGURATION:
 		buff := []byte{usbConfiguration}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_CONFIGURATION:
-		if setup.bmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
+		if setup.BmRequestType&usb_REQUEST_RECIPIENT == usb_REQUEST_DEVICE {
 			nrf.USBD.TASKS_EP0STATUS.Set(1)
 			for i := 1; i < len(endPoints); i++ {
 				initEndpoint(uint32(i), endPoints[i])
@@ -420,7 +420,7 @@ func handleStandardSetup(setup usbSetup) bool {
 				nrf.USBD.INTENSET.Set(nrf.USBD_INTENSET_ENDEPOUT0 << usb_HID_ENDPOINT_IN)
 			}
 
-			usbConfiguration = setup.wValueL
+			usbConfiguration = setup.WValueL
 			return true
 		} else {
 			return false
@@ -428,11 +428,11 @@ func handleStandardSetup(setup usbSetup) bool {
 
 	case usb_GET_INTERFACE:
 		buff := []byte{usbSetInterface}
-		sendUSBPacket(0, buff, setup.wLength)
+		sendUSBPacket(0, buff, setup.WLength)
 		return true
 
 	case usb_SET_INTERFACE:
-		usbSetInterface = setup.wValueL
+		usbSetInterface = setup.WValueL
 
 		nrf.USBD.TASKS_EP0STATUS.Set(1)
 		return true
@@ -442,9 +442,9 @@ func handleStandardSetup(setup usbSetup) bool {
 	}
 }
 
-func cdcSetup(setup usbSetup) bool {
-	if setup.bmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_GET_LINE_CODING {
+func cdcSetup(setup USBSetup) bool {
+	if setup.BmRequestType == usb_REQUEST_DEVICETOHOST_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_GET_LINE_CODING {
 			var b [cdcLineInfoSize]byte
 			b[0] = byte(usbLineInfo.dwDTERate)
 			b[1] = byte(usbLineInfo.dwDTERate >> 8)
@@ -454,27 +454,27 @@ func cdcSetup(setup usbSetup) bool {
 			b[5] = byte(usbLineInfo.bParityType)
 			b[6] = byte(usbLineInfo.bDataBits)
 
-			sendUSBPacket(0, b[:], setup.wLength)
+			sendUSBPacket(0, b[:], setup.WLength)
 			return true
 		}
 	}
 
-	if setup.bmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
-		if setup.bRequest == usb_CDC_SET_LINE_CODING {
+	if setup.BmRequestType == usb_REQUEST_HOSTTODEVICE_CLASS_INTERFACE {
+		if setup.BRequest == usb_CDC_SET_LINE_CODING {
 			epout0data_setlinecoding = true
 			nrf.USBD.TASKS_EP0RCVOUT.Set(1)
 			return true
 		}
 
-		if setup.bRequest == usb_CDC_SET_CONTROL_LINE_STATE {
-			usbLineInfo.lineState = setup.wValueL
+		if setup.BRequest == usb_CDC_SET_CONTROL_LINE_STATE {
+			usbLineInfo.lineState = setup.WValueL
 			if usbLineInfo.dwDTERate == 1200 && usbLineInfo.lineState&usb_CDC_LINESTATE_DTR == 0 {
 				EnterBootloader()
 			}
 			nrf.USBD.TASKS_EP0STATUS.Set(1)
 		}
 
-		if setup.bRequest == usb_CDC_SEND_BREAK {
+		if setup.BRequest == usb_CDC_SEND_BREAK {
 			nrf.USBD.TASKS_EP0STATUS.Set(1)
 		}
 		return true
@@ -530,7 +530,7 @@ func (usbcdc *USBCDC) handleEndpoint(ep uint32) {
 	nrf.USBD.SIZE.EPOUT[ep].Set(0)
 }
 
-func sendZlp() {
+func SendZlp() {
 	nrf.USBD.TASKS_EP0STATUS.Set(1)
 }
 
diff --git a/src/machine/usb.go b/src/machine/usb.go
index cc7e4534..2e5811b5 100644
--- a/src/machine/usb.go
+++ b/src/machine/usb.go
@@ -176,13 +176,6 @@ const (
 )
 
 // usbDeviceDescBank is the USB device endpoint descriptor.
-// typedef struct {
-// 	__IO USB_DEVICE_ADDR_Type      ADDR;        /**< \brief Offset: 0x000 (R/W 32) DEVICE_DESC_BANK Endpoint Bank, Adress of Data Buffer */
-// 	__IO USB_DEVICE_PCKSIZE_Type   PCKSIZE;     /**< \brief Offset: 0x004 (R/W 32) DEVICE_DESC_BANK Endpoint Bank, Packet Size */
-// 	__IO USB_DEVICE_EXTREG_Type    EXTREG;      /**< \brief Offset: 0x008 (R/W 16) DEVICE_DESC_BANK Endpoint Bank, Extended */
-// 	__IO USB_DEVICE_STATUS_BK_Type STATUS_BK;   /**< \brief Offset: 0x00A (R/W  8) DEVICE_DESC_BANK Enpoint Bank, Status of Bank */
-// 		 RoReg8                    Reserved1[0x5];
-//   } UsbDeviceDescBank;
 type usbDeviceDescBank struct {
 	ADDR      volatile.Register32
 	PCKSIZE   volatile.Register32
@@ -195,38 +188,23 @@ type usbDeviceDescriptor struct {
 	DeviceDescBank [2]usbDeviceDescBank
 }
 
-// typedef struct {
-// 	union {
-// 		uint8_t bmRequestType;
-// 		struct {
-// 			uint8_t direction : 5;
-// 			uint8_t type : 2;
-// 			uint8_t transferDirection : 1;
-// 		};
-// 	};
-// 	uint8_t bRequest;
-// 	uint8_t wValueL;
-// 	uint8_t wValueH;
-// 	uint16_t wIndex;
-// 	uint16_t wLength;
-// } USBSetup;
-type usbSetup struct {
-	bmRequestType uint8
-	bRequest      uint8
-	wValueL       uint8
-	wValueH       uint8
-	wIndex        uint16
-	wLength       uint16
+type USBSetup struct {
+	BmRequestType uint8
+	BRequest      uint8
+	WValueL       uint8
+	WValueH       uint8
+	WIndex        uint16
+	WLength       uint16
 }
 
-func newUSBSetup(data []byte) usbSetup {
-	u := usbSetup{}
-	u.bmRequestType = uint8(data[0])
-	u.bRequest = uint8(data[1])
-	u.wValueL = uint8(data[2])
-	u.wValueH = uint8(data[3])
-	u.wIndex = uint16(data[4]) | (uint16(data[5]) << 8)
-	u.wLength = uint16(data[6]) | (uint16(data[7]) << 8)
+func newUSBSetup(data []byte) USBSetup {
+	u := USBSetup{}
+	u.BmRequestType = uint8(data[0])
+	u.BRequest = uint8(data[1])
+	u.WValueL = uint8(data[2])
+	u.WValueH = uint8(data[3])
+	u.WIndex = uint16(data[4]) | (uint16(data[5]) << 8)
+	u.WLength = uint16(data[6]) | (uint16(data[7]) << 8)
 	return u
 }
 
@@ -299,41 +277,41 @@ func (usbcdc *USBCDC) Receive(data byte) {
 
 // sendDescriptor creates and sends the various USB descriptor types that
 // can be requested by the host.
-func sendDescriptor(setup usbSetup) {
-	switch setup.wValueH {
+func sendDescriptor(setup USBSetup) {
+	switch setup.WValueH {
 	case usb_CONFIGURATION_DESCRIPTOR_TYPE:
-		sendUSBPacket(0, usbDescriptor.Configuration, setup.wLength)
+		sendUSBPacket(0, usbDescriptor.Configuration, setup.WLength)
 		return
 	case usb_DEVICE_DESCRIPTOR_TYPE:
 		// composite descriptor
 		usbDescriptor.Configure(usb_VID, usb_PID)
-		sendUSBPacket(0, usbDescriptor.Device, setup.wLength)
+		sendUSBPacket(0, usbDescriptor.Device, setup.WLength)
 		return
 
 	case usb_STRING_DESCRIPTOR_TYPE:
-		switch setup.wValueL {
+		switch setup.WValueL {
 		case 0:
 			b := []byte{0x04, 0x03, 0x09, 0x04}
-			sendUSBPacket(0, b, setup.wLength)
+			sendUSBPacket(0, b, setup.WLength)
 
 		case usb_IPRODUCT:
 			b := make([]byte, (len(usb_STRING_PRODUCT)<<1)+2)
 			strToUTF16LEDescriptor(usb_STRING_PRODUCT, b)
-			sendUSBPacket(0, b, setup.wLength)
+			sendUSBPacket(0, b, setup.WLength)
 
 		case usb_IMANUFACTURER:
 			b := make([]byte, (len(usb_STRING_MANUFACTURER)<<1)+2)
 			strToUTF16LEDescriptor(usb_STRING_MANUFACTURER, b)
-			sendUSBPacket(0, b, setup.wLength)
+			sendUSBPacket(0, b, setup.WLength)
 
 		case usb_ISERIAL:
 			// TODO: allow returning a product serial number
-			sendZlp()
+			SendZlp()
 		}
 		return
 	case usb_HID_REPORT_TYPE:
-		if h, ok := usbDescriptor.HID[setup.wIndex]; ok {
-			sendUSBPacket(0, h, setup.wLength)
+		if h, ok := usbDescriptor.HID[setup.WIndex]; ok {
+			sendUSBPacket(0, h, setup.WLength)
 			return
 		}
 	case usb_DEVICE_QUALIFIER:
@@ -342,7 +320,7 @@ func sendDescriptor(setup usbSetup) {
 	}
 
 	// do not know how to handle this message, so return zero
-	sendZlp()
+	SendZlp()
 	return
 }