diff --git a/adapter_nrf51.go b/adapter_nrf51.go
index a46efb3..2b98cc1 100644
--- a/adapter_nrf51.go
+++ b/adapter_nrf51.go
@@ -42,7 +42,7 @@ func handleEvent() {
 		gapEvent := eventBuf.evt.unionfield_gap_evt()
 		switch id {
 		case C.BLE_GAP_EVT_CONNECTED:
-			currentConnection.Reg = gapEvent.conn_handle
+			currentConnection.handle.Reg = uint16(gapEvent.conn_handle)
 			DefaultAdapter.connectHandler(Address{}, true)
 		case C.BLE_GAP_EVT_DISCONNECTED:
 			if defaultAdvertisement.isAdvertising.Get() != 0 {
@@ -54,7 +54,7 @@ func handleEvent() {
 				// necessary.
 				defaultAdvertisement.start()
 			}
-			currentConnection.Reg = C.BLE_CONN_HANDLE_INVALID
+			currentConnection.handle.Reg = C.BLE_CONN_HANDLE_INVALID
 			DefaultAdapter.connectHandler(Address{}, false)
 		case C.BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
 			// Respond with the default PPCP connection parameters by passing
@@ -109,5 +109,5 @@ func (a *Adapter) Address() (MACAddress, error) {
 	if errCode != 0 {
 		return MACAddress{}, Error(errCode)
 	}
-	return MACAddress{MAC: addr.addr}, nil
+	return MACAddress{MAC: makeAddress(addr.addr)}, nil
 }
diff --git a/adapter_nrf528xx-full.go b/adapter_nrf528xx-full.go
index 64dc954..6ce048b 100644
--- a/adapter_nrf528xx-full.go
+++ b/adapter_nrf528xx-full.go
@@ -30,7 +30,7 @@ func handleEvent() {
 				if debug {
 					println("evt: connected in peripheral role")
 				}
-				currentConnection.Reg = gapEvent.conn_handle
+				currentConnection.handle.Reg = uint16(gapEvent.conn_handle)
 				DefaultAdapter.connectHandler(Address{}, true)
 			case C.BLE_GAP_ROLE_CENTRAL:
 				if debug {
@@ -46,11 +46,11 @@ func handleEvent() {
 			}
 			// Clean up state for this connection.
 			for i, cb := range gattcNotificationCallbacks {
-				if cb.connectionHandle == currentConnection.Reg {
+				if uint16(cb.connectionHandle) == currentConnection.handle.Reg {
 					gattcNotificationCallbacks[i].valueHandle = 0 // 0 means invalid
 				}
 			}
-			currentConnection.Reg = C.BLE_CONN_HANDLE_INVALID
+			currentConnection.handle.Reg = C.BLE_CONN_HANDLE_INVALID
 			// Auto-restart advertisement if needed.
 			if defaultAdvertisement.isAdvertising.Get() != 0 {
 				// The advertisement was running but was automatically stopped
@@ -64,7 +64,7 @@ func handleEvent() {
 			DefaultAdapter.connectHandler(Address{}, false)
 		case C.BLE_GAP_EVT_ADV_REPORT:
 			advReport := gapEvent.params.unionfield_adv_report()
-			if debug && &scanReportBuffer.data[0] != advReport.data.p_data {
+			if debug && &scanReportBuffer.data[0] != (*byte)(unsafe.Pointer(advReport.data.p_data)) {
 				// Sanity check.
 				panic("scanReportBuffer != advReport.p_data")
 			}
@@ -73,7 +73,7 @@ func handleEvent() {
 			scanReportBuffer.len = byte(advReport.data.len)
 			globalScanResult.RSSI = int16(advReport.rssi)
 			globalScanResult.Address = Address{
-				MACAddress{MAC: advReport.peer_addr.addr,
+				MACAddress{MAC: makeAddress(advReport.peer_addr.addr),
 					isRandom: advReport.peer_addr.bitfield_addr_type() != 0},
 			}
 			globalScanResult.AdvertisementPayload = &scanReportBuffer
diff --git a/adapter_nrf528xx-peripheral.go b/adapter_nrf528xx-peripheral.go
index 3b4ab51..5e9f181 100644
--- a/adapter_nrf528xx-peripheral.go
+++ b/adapter_nrf528xx-peripheral.go
@@ -27,13 +27,13 @@ func handleEvent() {
 			if debug {
 				println("evt: connected in peripheral role")
 			}
-			currentConnection.Reg = gapEvent.conn_handle
+			currentConnection.handle.Reg = uint16(gapEvent.conn_handle)
 			DefaultAdapter.connectHandler(Address{}, true)
 		case C.BLE_GAP_EVT_DISCONNECTED:
 			if debug {
 				println("evt: disconnected")
 			}
-			currentConnection.Reg = C.BLE_CONN_HANDLE_INVALID
+			currentConnection.handle.Reg = C.BLE_CONN_HANDLE_INVALID
 			// Auto-restart advertisement if needed.
 			if defaultAdvertisement.isAdvertising.Get() != 0 {
 				// The advertisement was running but was automatically stopped
diff --git a/adapter_nrf528xx.go b/adapter_nrf528xx.go
index 7c47f4e..d05ab02 100644
--- a/adapter_nrf528xx.go
+++ b/adapter_nrf528xx.go
@@ -46,7 +46,7 @@ func (a *Adapter) enable() error {
 	}
 
 	// Enable the BLE stack.
-	appRAMBase := uint32(uintptr(unsafe.Pointer(&appRAMBase)))
+	appRAMBase := C.uint32_t(uintptr(unsafe.Pointer(&appRAMBase)))
 	errCode = C.sd_ble_enable(&appRAMBase)
 	return makeError(errCode)
 }
@@ -57,5 +57,5 @@ func (a *Adapter) Address() (MACAddress, error) {
 	if errCode != 0 {
 		return MACAddress{}, Error(errCode)
 	}
-	return MACAddress{MAC: addr.addr}, nil
+	return MACAddress{MAC: makeAddress(addr.addr)}, nil
 }
diff --git a/adapter_sd.go b/adapter_sd.go
index 24963b3..44590ab 100644
--- a/adapter_sd.go
+++ b/adapter_sd.go
@@ -28,7 +28,7 @@ var (
 )
 
 // There can only be one connection at a time in the default configuration.
-var currentConnection = volatile.Register16{C.BLE_CONN_HANDLE_INVALID}
+var currentConnection = volatileHandle{handle: volatile.Register16{C.BLE_CONN_HANDLE_INVALID}}
 
 // Globally allocated buffer for incoming SoftDevice events.
 var eventBuf struct {
@@ -60,7 +60,7 @@ var DefaultAdapter = &Adapter{isDefault: true,
 		return
 	}}
 
-var eventBufLen uint16
+var eventBufLen C.uint16_t
 
 // Enable configures the BLE stack. It must be called before any
 // Bluetooth-related calls (unless otherwise indicated).
@@ -72,8 +72,8 @@ func (a *Adapter) Enable() error {
 	// Enable the IRQ that handles all events.
 	intr := interrupt.New(nrf.IRQ_SWI2, func(interrupt.Interrupt) {
 		for {
-			eventBufLen = uint16(unsafe.Sizeof(eventBuf))
-			errCode := C.sd_ble_evt_get((*uint8)(unsafe.Pointer(&eventBuf)), &eventBufLen)
+			eventBufLen = C.uint16_t(unsafe.Sizeof(eventBuf))
+			errCode := C.sd_ble_evt_get((*C.uint8_t)(unsafe.Pointer(&eventBuf)), &eventBufLen)
 			if errCode != 0 {
 				// Possible error conditions:
 				//  * NRF_ERROR_NOT_FOUND: no events left, break
@@ -97,7 +97,7 @@ func (a *Adapter) Enable() error {
 		return err
 	}
 
-	errCode := C.sd_ble_gap_device_name_set(&secModeOpen, &defaultDeviceName[0], uint16(len(defaultDeviceName)))
+	errCode := C.sd_ble_gap_device_name_set(&secModeOpen, (*C.uint8_t)(unsafe.Pointer(&defaultDeviceName[0])), C.uint16_t(len(defaultDeviceName)))
 	if errCode != 0 {
 		return Error(errCode)
 	}
@@ -116,7 +116,7 @@ func (a *Adapter) Enable() error {
 // play well with the SoftDevice. Restore interrupts to the previous state with
 // RestoreInterrupts.
 func DisableInterrupts() uintptr {
-	var is_nested_critical_region uint8
+	var is_nested_critical_region C.uint8_t
 	C.sd_nvic_critical_region_enter(&is_nested_critical_region)
 	return uintptr(is_nested_critical_region)
 }
@@ -125,5 +125,43 @@ func DisableInterrupts() uintptr {
 // DisableInterrupts. The mask parameter must be the value returned by
 // DisableInterrupts.
 func RestoreInterrupts(mask uintptr) {
-	C.sd_nvic_critical_region_exit(uint8(mask))
+	C.sd_nvic_critical_region_exit(C.uint8_t(mask))
+}
+
+// Wrapper for volatile.Register16 that uses C.uint16_t instead of uint16, for
+// easier interoperability with C.
+type volatileHandle struct {
+	handle volatile.Register16
+}
+
+func (a *volatileHandle) Set(handle C.uint16_t) {
+	a.handle.Set(uint16(handle))
+}
+
+func (a *volatileHandle) Get() C.uint16_t {
+	return C.uint16_t(a.handle.Get())
+}
+
+// Convert a SoftDevice MAC address into a Go MAC address.
+func makeAddress(mac [6]C.uint8_t) MAC {
+	return MAC{
+		uint8(mac[0]),
+		uint8(mac[1]),
+		uint8(mac[2]),
+		uint8(mac[3]),
+		uint8(mac[4]),
+		uint8(mac[5]),
+	}
+}
+
+// Convert a Go MAC address into a SoftDevice MAC Address.
+func makeSDAddress(mac MAC) [6]C.uint8_t {
+	return [6]C.uint8_t{
+		C.uint8_t(mac[0]),
+		C.uint8_t(mac[1]),
+		C.uint8_t(mac[2]),
+		C.uint8_t(mac[3]),
+		C.uint8_t(mac[4]),
+		C.uint8_t(mac[5]),
+	}
 }
diff --git a/error_sd.go b/error_sd.go
index 16c43ee..ad1f371 100644
--- a/error_sd.go
+++ b/error_sd.go
@@ -2,6 +2,7 @@
 
 package bluetooth
 
+// #include <stdint.h>
 // #include "nrf_error.h"
 // #include "nrf_error_sdm.h"
 import "C"
@@ -83,7 +84,7 @@ func (e Error) Error() string {
 
 // makeError returns an error (using the Error type) if the error code is
 // non-zero, otherwise it returns nil. It is used with internal API calls.
-func makeError(code uint32) error {
+func makeError(code C.uint32_t) error {
 	if code != 0 {
 		return Error(code)
 	}
diff --git a/gap_nrf51.go b/gap_nrf51.go
index f37f59b..9ec6d7f 100644
--- a/gap_nrf51.go
+++ b/gap_nrf51.go
@@ -15,6 +15,7 @@ import "C"
 import (
 	"runtime/volatile"
 	"time"
+	"unsafe"
 )
 
 // Address contains a Bluetooth MAC address.
@@ -52,7 +53,7 @@ func (a *Advertisement) Configure(options AdvertisementOptions) error {
 		return errAdvertisementPacketTooBig
 	}
 
-	errCode := C.sd_ble_gap_adv_data_set(&payload.data[0], payload.len, nil, 0)
+	errCode := C.sd_ble_gap_adv_data_set((*C.uint8_t)(unsafe.Pointer(&payload.data[0])), C.uint8_t(payload.len), nil, 0)
 	a.interval = options.Interval
 	return makeError(errCode)
 }
@@ -73,11 +74,11 @@ func (a *Advertisement) Stop() error {
 
 // Low-level version of Start. Used to restart advertisement when a connection
 // is lost.
-func (a *Advertisement) start() uint32 {
+func (a *Advertisement) start() C.uint32_t {
 	params := C.ble_gap_adv_params_t{
 		_type:    C.BLE_GAP_ADV_TYPE_ADV_IND,
 		fp:       C.BLE_GAP_ADV_FP_ANY,
-		interval: uint16(a.interval),
+		interval: C.uint16_t(a.interval),
 		timeout:  0, // no timeout
 	}
 	return C.sd_ble_gap_adv_start_noescape(params)
diff --git a/gap_nrf528xx-advertisement.go b/gap_nrf528xx-advertisement.go
index 9b3a653..1d72604 100644
--- a/gap_nrf528xx-advertisement.go
+++ b/gap_nrf528xx-advertisement.go
@@ -5,6 +5,7 @@ package bluetooth
 import (
 	"runtime/volatile"
 	"time"
+	"unsafe"
 )
 
 /*
@@ -19,7 +20,7 @@ type Address struct {
 
 // Advertisement encapsulates a single advertisement instance.
 type Advertisement struct {
-	handle        uint8
+	handle        C.uint8_t
 	isAdvertising volatile.Register8
 	payload       rawAdvertisementPayload
 }
@@ -57,14 +58,14 @@ func (a *Advertisement) Configure(options AdvertisementOptions) error {
 
 	data := C.ble_gap_adv_data_t{}
 	data.adv_data = C.ble_data_t{
-		p_data: &a.payload.data[0],
-		len:    uint16(a.payload.len),
+		p_data: (*C.uint8_t)(unsafe.Pointer(&a.payload.data[0])),
+		len:    C.uint16_t(a.payload.len),
 	}
 	params := C.ble_gap_adv_params_t{
 		properties: C.ble_gap_adv_properties_t{
 			_type: C.BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED,
 		},
-		interval: uint32(options.Interval),
+		interval: C.uint32_t(options.Interval),
 	}
 	errCode := C.sd_ble_gap_adv_set_configure(&a.handle, &data, &params)
 	return makeError(errCode)
diff --git a/gap_nrf528xx-central.go b/gap_nrf528xx-central.go
index d3faa4a..44fe683 100644
--- a/gap_nrf528xx-central.go
+++ b/gap_nrf528xx-central.go
@@ -7,6 +7,7 @@ import (
 	"errors"
 	"runtime/volatile"
 	"time"
+	"unsafe"
 )
 
 /*
@@ -40,12 +41,12 @@ func (a *Adapter) Scan(callback func(*Adapter, ScanResult)) error {
 	scanParams := C.ble_gap_scan_params_t{}
 	scanParams.set_bitfield_extended(0)
 	scanParams.set_bitfield_active(0)
-	scanParams.interval = uint16(NewDuration(40 * time.Millisecond))
-	scanParams.window = uint16(NewDuration(30 * time.Millisecond))
+	scanParams.interval = C.uint16_t(NewDuration(40 * time.Millisecond))
+	scanParams.window = C.uint16_t(NewDuration(30 * time.Millisecond))
 	scanParams.timeout = C.BLE_GAP_SCAN_TIMEOUT_UNLIMITED
 	scanReportBufferInfo := C.ble_data_t{
-		p_data: &scanReportBuffer.data[0],
-		len:    uint16(len(scanReportBuffer.data)),
+		p_data: (*C.uint8_t)(unsafe.Pointer(&scanReportBuffer.data[0])),
+		len:    C.uint16_t(len(scanReportBuffer.data)),
 	}
 	errCode := C.sd_ble_gap_scan_start(&scanParams, &scanReportBufferInfo)
 	if errCode != 0 {
@@ -93,13 +94,13 @@ func (a *Adapter) StopScan() error {
 
 // Device is a connection to a remote peripheral.
 type Device struct {
-	connectionHandle uint16
+	connectionHandle C.uint16_t
 }
 
 // In-progress connection attempt.
 var connectionAttempt struct {
 	state            volatile.Register8 // 0 means unused, 1 means connecting, 2 means ready (connected or timeout)
-	connectionHandle uint16
+	connectionHandle C.uint16_t
 }
 
 // Connect starts a connection attempt to the given peripheral device address.
@@ -111,7 +112,7 @@ var connectionAttempt struct {
 func (a *Adapter) Connect(address Address, params ConnectionParams) (*Device, error) {
 	// Construct an address object as used in the SoftDevice.
 	var addr C.ble_gap_addr_t
-	addr.addr = address.MAC
+	addr.addr = makeSDAddress(address.MAC)
 	if address.IsRandom() {
 		switch address.MAC[5] >> 6 {
 		case 0b11:
@@ -142,13 +143,13 @@ func (a *Adapter) Connect(address Address, params ConnectionParams) (*Device, er
 	scanParams := C.ble_gap_scan_params_t{}
 	scanParams.set_bitfield_extended(0)
 	scanParams.set_bitfield_active(0)
-	scanParams.interval = uint16(NewDuration(40 * time.Millisecond))
-	scanParams.window = uint16(NewDuration(30 * time.Millisecond))
-	scanParams.timeout = uint16(params.ConnectionTimeout)
+	scanParams.interval = C.uint16_t(NewDuration(40 * time.Millisecond))
+	scanParams.window = C.uint16_t(NewDuration(30 * time.Millisecond))
+	scanParams.timeout = C.uint16_t(params.ConnectionTimeout)
 
 	connectionParams := C.ble_gap_conn_params_t{
-		min_conn_interval: uint16(params.MinInterval) / 2,
-		max_conn_interval: uint16(params.MaxInterval) / 2,
+		min_conn_interval: C.uint16_t(params.MinInterval) / 2,
+		max_conn_interval: C.uint16_t(params.MaxInterval) / 2,
 		slave_latency:     0,   // mostly relevant to connected keyboards etc
 		conn_sup_timeout:  200, // 2 seconds (in 10ms units), the minimum recommended by Apple
 	}
diff --git a/gattc_sd.go b/gattc_sd.go
index 018d398..9f8fb8f 100644
--- a/gattc_sd.go
+++ b/gattc_sd.go
@@ -11,6 +11,7 @@ import (
 	"device/arm"
 	"errors"
 	"runtime/volatile"
+	"unsafe"
 )
 
 const (
@@ -28,8 +29,8 @@ var (
 // program and the event handler.
 var discoveringService struct {
 	state       volatile.Register8 // 0 means nothing happening, 1 means in progress, 2 means found something
-	startHandle volatile.Register16
-	endHandle   volatile.Register16
+	startHandle volatileHandle
+	endHandle   volatileHandle
 	uuid        C.ble_uuid_t
 }
 
@@ -38,9 +39,9 @@ var discoveringService struct {
 type DeviceService struct {
 	uuid shortUUID
 
-	connectionHandle uint16
-	startHandle      uint16
-	endHandle        uint16
+	connectionHandle C.uint16_t
+	startHandle      C.uint16_t
+	endHandle        C.uint16_t
 }
 
 // UUID returns the UUID for this DeviceService.
@@ -76,7 +77,7 @@ func (d *Device) DiscoverServices(uuids []UUID) ([]DeviceService, error) {
 	if len(uuids) > 0 {
 		shortUUIDs = make([]C.ble_uuid_t, sz)
 		for i, uuid := range uuids {
-			var errCode uint32
+			var errCode C.uint32_t
 			shortUUIDs[i], errCode = uuid.shortUUID()
 			if errCode != 0 {
 				return nil, Error(errCode)
@@ -86,7 +87,7 @@ func (d *Device) DiscoverServices(uuids []UUID) ([]DeviceService, error) {
 
 	numFound := 0
 
-	var startHandle uint16 = 1
+	var startHandle C.uint16_t = 1
 
 	for i := 0; i < sz; i++ {
 		var suuid C.ble_uuid_t
@@ -96,7 +97,7 @@ func (d *Device) DiscoverServices(uuids []UUID) ([]DeviceService, error) {
 
 		// Start discovery of this service.
 		discoveringService.state.Set(1)
-		var errCode uint32
+		var errCode C.uint32_t
 		if len(uuids) > 0 {
 			errCode = C.sd_ble_gattc_primary_services_discover(d.connectionHandle, startHandle, &suuid)
 		} else {
@@ -159,9 +160,9 @@ func (d *Device) DiscoverServices(uuids []UUID) ([]DeviceService, error) {
 type DeviceCharacteristic struct {
 	uuid shortUUID
 
-	connectionHandle uint16
-	valueHandle      uint16
-	cccdHandle       uint16
+	connectionHandle C.uint16_t
+	valueHandle      C.uint16_t
+	cccdHandle       C.uint16_t
 	permissions      CharacteristicPermissions
 }
 
@@ -175,7 +176,7 @@ func (c *DeviceCharacteristic) UUID() UUID {
 var discoveringCharacteristic struct {
 	uuid         C.ble_uuid_t
 	char_props   C.ble_gatt_char_props_t
-	handle_value volatile.Register16
+	handle_value volatileHandle
 }
 
 // DiscoverCharacteristics discovers characteristics in this service. Pass a
@@ -204,7 +205,7 @@ func (s *DeviceService) DiscoverCharacteristics(uuids []UUID) ([]DeviceCharacter
 	if len(uuids) > 0 {
 		shortUUIDs = make([]C.ble_uuid_t, sz)
 		for i, uuid := range uuids {
-			var errCode uint32
+			var errCode C.uint32_t
 			shortUUIDs[i], errCode = uuid.shortUUID()
 			if errCode != 0 {
 				return nil, Error(errCode)
@@ -324,8 +325,8 @@ func (c DeviceCharacteristic) WriteWithoutResponse(p []byte) (n int, err error)
 		write_op: C.BLE_GATT_OP_WRITE_CMD,
 		handle:   c.valueHandle,
 		offset:   0,
-		len:      uint16(len(p)),
-		p_value:  &p[0],
+		len:      C.uint16_t(len(p)),
+		p_value:  (*C.uint8_t)(unsafe.Pointer(&p[0])),
 	})
 	if errCode != 0 {
 		return 0, Error(errCode)
@@ -334,8 +335,8 @@ func (c DeviceCharacteristic) WriteWithoutResponse(p []byte) (n int, err error)
 }
 
 type gattcNotificationCallback struct {
-	connectionHandle uint16
-	valueHandle      uint16 // may be 0 if the slot is empty
+	connectionHandle C.uint16_t
+	valueHandle      C.uint16_t // may be 0 if the slot is empty
 	callback         func([]byte)
 }
 
@@ -400,7 +401,7 @@ func (c DeviceCharacteristic) EnableNotifications(callback func(buf []byte)) err
 	}
 
 	// Write to the CCCD to enable notifications. Don't wait for a response.
-	value := [2]byte{0x01, 0x00} // 0x0001 enables notifications (and disables indications)
+	value := [2]C.uint8_t{0x01, 0x00} // 0x0001 enables notifications (and disables indications)
 	errCode := C.sd_ble_gattc_write(c.connectionHandle, &C.ble_gattc_write_params_t{
 		write_op: C.BLE_GATT_OP_WRITE_CMD,
 		handle:   c.cccdHandle,
@@ -414,9 +415,9 @@ func (c DeviceCharacteristic) EnableNotifications(callback func(buf []byte)) err
 // A global used to pass information from the event handler back to the
 // Read function below.
 var readingCharacteristic struct {
-	handle_value volatile.Register16
-	offset       uint16
-	length       uint16
+	handle_value volatileHandle
+	offset       C.uint16_t
+	length       C.uint16_t
 	value        []byte
 }
 
diff --git a/gatts_sd.go b/gatts_sd.go
index 970f776..afd05be 100644
--- a/gatts_sd.go
+++ b/gatts_sd.go
@@ -17,11 +17,12 @@ static inline uint32_t sd_ble_gatts_value_set_noescape(uint16_t conn_handle, uin
 }
 */
 import "C"
+import "unsafe"
 
 // Characteristic is a single characteristic in a service. It has an UUID and a
 // value.
 type Characteristic struct {
-	handle      uint16
+	handle      C.uint16_t
 	permissions CharacteristicPermissions
 }
 
@@ -32,18 +33,18 @@ func (a *Adapter) AddService(service *Service) error {
 	if errCode != 0 {
 		return Error(errCode)
 	}
-	errCode = C.sd_ble_gatts_service_add(C.BLE_GATTS_SRVC_TYPE_PRIMARY, &uuid, &service.handle)
+	errCode = C.sd_ble_gatts_service_add(C.BLE_GATTS_SRVC_TYPE_PRIMARY, &uuid, (*C.uint16_t)(unsafe.Pointer(&service.handle)))
 	if errCode != 0 {
 		return Error(errCode)
 	}
 	for _, char := range service.Characteristics {
 		metadata := C.ble_gatts_char_md_t{}
-		metadata.char_props.set_bitfield_broadcast(uint8(char.Flags>>0) & 1)
-		metadata.char_props.set_bitfield_read(uint8(char.Flags>>1) & 1)
-		metadata.char_props.set_bitfield_write_wo_resp(uint8(char.Flags>>2) & 1)
-		metadata.char_props.set_bitfield_write(uint8(char.Flags>>3) & 1)
-		metadata.char_props.set_bitfield_notify(uint8(char.Flags>>4) & 1)
-		metadata.char_props.set_bitfield_indicate(uint8(char.Flags>>5) & 1)
+		metadata.char_props.set_bitfield_broadcast(C.uint8_t(char.Flags>>0) & 1)
+		metadata.char_props.set_bitfield_read(C.uint8_t(char.Flags>>1) & 1)
+		metadata.char_props.set_bitfield_write_wo_resp(C.uint8_t(char.Flags>>2) & 1)
+		metadata.char_props.set_bitfield_write(C.uint8_t(char.Flags>>3) & 1)
+		metadata.char_props.set_bitfield_notify(C.uint8_t(char.Flags>>4) & 1)
+		metadata.char_props.set_bitfield_indicate(C.uint8_t(char.Flags>>5) & 1)
 		handles := C.ble_gatts_char_handles_t{}
 		charUUID, errCode := char.UUID.shortUUID()
 		if errCode != 0 {
@@ -55,16 +56,16 @@ func (a *Adapter) AddService(service *Service) error {
 				read_perm:  secModeOpen,
 				write_perm: secModeOpen,
 			},
-			init_len:  uint16(len(char.Value)),
+			init_len:  C.uint16_t(len(char.Value)),
 			init_offs: 0,
 			max_len:   20, // This is a conservative maximum length.
 		}
 		if len(char.Value) != 0 {
-			value.p_value = &char.Value[0]
+			value.p_value = (*C.uint8_t)(unsafe.Pointer(&char.Value[0]))
 		}
 		value.p_attr_md.set_bitfield_vloc(C.BLE_GATTS_VLOC_STACK)
 		value.p_attr_md.set_bitfield_vlen(1)
-		errCode = C.sd_ble_gatts_characteristic_add(service.handle, &metadata, &value, &handles)
+		errCode = C.sd_ble_gatts_characteristic_add(C.uint16_t(service.handle), &metadata, &value, &handles)
 		if errCode != 0 {
 			return Error(errCode)
 		}
@@ -88,13 +89,13 @@ func (a *Adapter) AddService(service *Service) error {
 // charWriteHandler contains a handler->callback mapping for characteristic
 // writes.
 type charWriteHandler struct {
-	handle   uint16
+	handle   C.uint16_t
 	callback func(connection Connection, offset int, value []byte)
 }
 
 // getCharWriteHandler returns a characteristic write handler if one matches the
 // handle, or nil otherwise.
-func (a *Adapter) getCharWriteHandler(handle uint16) *charWriteHandler {
+func (a *Adapter) getCharWriteHandler(handle C.uint16_t) *charWriteHandler {
 	// Look through all handlers for a match.
 	// There is probably a way to do this more efficiently (with a hashmap for
 	// example) but the number of event handlers is likely low and improving
@@ -124,8 +125,8 @@ func (c *Characteristic) Write(p []byte) (n int, err error) {
 			c.handle,
 			C.BLE_GATT_HVX_NOTIFICATION,
 			0,
-			p_len,
-			&p[0],
+			C.uint16_t(p_len),
+			(*C.uint8_t)(unsafe.Pointer(&p[0])),
 		)
 
 		// Check for some expected errors. Don't report them as errors, but
@@ -145,8 +146,8 @@ func (c *Characteristic) Write(p []byte) (n int, err error) {
 	}
 
 	errCode := C.sd_ble_gatts_value_set_noescape(C.BLE_CONN_HANDLE_INVALID, c.handle, C.ble_gatts_value_t{
-		len:     uint16(len(p)),
-		p_value: &p[0],
+		len:     C.uint16_t(len(p)),
+		p_value: (*C.uint8_t)(unsafe.Pointer(&p[0])),
 	})
 	if errCode != 0 {
 		return 0, Error(errCode)
diff --git a/go.mod b/go.mod
index ae68982..85559c2 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 	github.com/saltosystems/winrt-go v0.0.0-20230921082907-2ab5b7d431e1
 	github.com/tinygo-org/cbgo v0.0.4
 	golang.org/x/crypto v0.12.0
-	tinygo.org/x/drivers v0.25.0
+	tinygo.org/x/drivers v0.26.1-0.20230922160320-ed51435c2ef6
 	tinygo.org/x/tinyfont v0.4.0
 	tinygo.org/x/tinyterm v0.3.0
 )
diff --git a/go.sum b/go.sum
index 57a0225..8dd63d1 100644
--- a/go.sum
+++ b/go.sum
@@ -1,24 +1,18 @@
-github.com/bgould/http v0.0.0-20190627042742-d268792bdee7/go.mod h1:BTqvVegvwifopl4KTEDth6Zezs9eR+lCWhvGKvkxJHE=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/eclipse/paho.mqtt.golang v1.2.0/go.mod h1:H9keYFcgq3Qr5OUJm/JZI/i6U7joQ8SYLhZwfeOo6Ts=
 github.com/fatih/structs v1.1.0 h1:Q7juDM0QtcnhCpeyLGQKyg4TOIghuNXrkL32pHAUMxo=
 github.com/fatih/structs v1.1.0/go.mod h1:9NiDSp5zOcgEDl+j00MP/WkGVPOlPRLejGD8Ga6PJ7M=
-github.com/frankban/quicktest v1.10.2/go.mod h1:K+q6oSqb0W0Ininfk863uOk1lMy69l/P6txr3mVT54s=
 github.com/go-ole/go-ole v1.2.6 h1:/Fpf6oFPoeFik9ty7siob0G6Ke8QvQEuVcuChpwXzpY=
 github.com/go-ole/go-ole v1.2.6/go.mod h1:pprOEPIfldk/42T2oK7lQ4v4JSDwmV0As9GaiUsvbm0=
 github.com/godbus/dbus/v5 v5.0.3/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/godbus/dbus/v5 v5.1.0 h1:4KLkAxT3aOY8Li4FRJe/KvhoNFFxo0m6fNuFUO8QJUk=
 github.com/godbus/dbus/v5 v5.1.0/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 h1:El6M4kTTCOh6aBiKaUGG7oYTSPP8MxqL4YI3kZKwcP4=
 github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510/go.mod h1:pupxD2MaaD3pAXIBCelhxNneeOaAeabZDe5s4K6zSpQ=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/hajimehoshi/go-jisx0208 v1.0.0/go.mod h1:yYxEStHL7lt9uL+AbdWgW9gBumwieDoZCiB1f/0X0as=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
 github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
-github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/muka/go-bluetooth v0.0.0-20221213043340-85dc80edc4e1 h1:BuVRHr4HHJbk1DHyWkArJ7E8J/VA8ncCr/VLnQFazBo=
@@ -28,7 +22,6 @@ github.com/paypal/gatt v0.0.0-20151011220935-4ae819d591cf/go.mod h1:+AwQL2mK3Pd3
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/sago35/go-bdf v0.0.0-20200313142241-6c17821c91c4/go.mod h1:rOebXGuMLsXhZAC6mF/TjxONsm45498ZyzVhel++6KM=
 github.com/saltosystems/winrt-go v0.0.0-20230921082907-2ab5b7d431e1 h1:L2YoWezgwpAZ2SEKjXk6yLnwOkM3u7mXq/mKuJeEpFM=
 github.com/saltosystems/winrt-go v0.0.0-20230921082907-2ab5b7d431e1/go.mod h1:CIltaIm7qaANUIvzr0Vmz71lmQMAIbGJ7cvgzX7FMfA=
 github.com/sirupsen/logrus v1.5.0/go.mod h1:+F7Ogzej0PZc/94MaYx/nvG9jOFMD2osvC3s+Squfpo=
@@ -43,19 +36,16 @@ github.com/stretchr/testify v1.7.5 h1:s5PTfem8p8EbKQOctVV53k6jCJt3UX4IEJzwh+C324
 github.com/suapapa/go_eddystone v1.3.1/go.mod h1:bXC11TfJOS+3g3q/Uzd7FKd5g62STQEfeEIhcKe4Qy8=
 github.com/tinygo-org/cbgo v0.0.4 h1:3D76CRYbH03Rudi8sEgs/YO0x3JIMdyq8jlQtk/44fU=
 github.com/tinygo-org/cbgo v0.0.4/go.mod h1:7+HgWIHd4nbAz0ESjGlJ1/v9LDU1Ox8MGzP9mah/fLk=
-github.com/valyala/fastjson v1.6.3/go.mod h1:CLCAqky6SMuOcxStkYQvblddUtoRxhYMGLrsQns1aXY=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.12.0 h1:tFM/ta59kqch6LlvYnPa0yx5a83cL2nHflFhYKvv9Yk=
 golang.org/x/crypto v0.12.0/go.mod h1:NF0Gs7EO5K4qLn+Ylc+fih8BSTeIjAP05siRnAh98yw=
-golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
-golang.org/x/net v0.0.0-20210614182718-04defd469f4e/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -64,38 +54,24 @@ golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190916202348-b4ddaad3f8a3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
 golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.11.0 h1:F9tnn/DA/Im8nCwm+fX+1/eBwi4qFjRT++MhtVC4ZX0=
 golang.org/x/term v0.11.0/go.mod h1:zC9APTIj3jG3FdV/Ons+XE1riIZXG4aZ4GTHiPZJPIU=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200925191224-5d1fdd8fa346/go.mod h1:z6u4i615ZeAfBE4XtMziQW1fSVJXACjjbWkB/mvPzlU=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
-tinygo.org/x/drivers v0.14.0/go.mod h1:uT2svMq3EpBZpKkGO+NQHjxjGf1f42ra4OnMMwQL2aI=
-tinygo.org/x/drivers v0.15.1/go.mod h1:uT2svMq3EpBZpKkGO+NQHjxjGf1f42ra4OnMMwQL2aI=
-tinygo.org/x/drivers v0.16.0/go.mod h1:uT2svMq3EpBZpKkGO+NQHjxjGf1f42ra4OnMMwQL2aI=
-tinygo.org/x/drivers v0.19.0/go.mod h1:uJD/l1qWzxzLx+vcxaW0eY464N5RAgFi1zTVzASFdqI=
-tinygo.org/x/drivers v0.25.0 h1:MFnec5lY8Sxk1bIfqQWsflIbxcpAFbohWhg/qZ7psdM=
-tinygo.org/x/drivers v0.25.0/go.mod h1:v+mXaA4cgpz/YZJ3ZPm/86bYQJAXTaYtMkHlVwbodbw=
-tinygo.org/x/tinyfont v0.2.1/go.mod h1:eLqnYSrFRjt5STxWaMeOWJTzrKhXqpWw7nU3bPfKOAM=
-tinygo.org/x/tinyfont v0.3.0/go.mod h1:+TV5q0KpwSGRWnN+ITijsIhrWYJkoUCp9MYELjKpAXk=
+tinygo.org/x/drivers v0.26.1-0.20230922160320-ed51435c2ef6 h1:w18u47MirULgAl+bP0piUGu5VUZDs7TvXwHASEVXqHk=
+tinygo.org/x/drivers v0.26.1-0.20230922160320-ed51435c2ef6/go.mod h1:X7utcg3yfFUFuKLOMTZD56eztXMjpkcf8OHldfTBsjw=
 tinygo.org/x/tinyfont v0.4.0 h1:XexPKEKiHInf6p4CMCJwsIheVPY0T46HUs6ictYyZfE=
 tinygo.org/x/tinyfont v0.4.0/go.mod h1:7nVj3j3geqBoPDzpFukAhF1C8AP9YocMsZy0HSAcGCA=
-tinygo.org/x/tinyfs v0.1.0/go.mod h1:ysc8Y92iHfhTXeyEM9+c7zviUQ4fN9UCFgSOFfMWv20=
-tinygo.org/x/tinyterm v0.1.0/go.mod h1:/DDhNnGwNF2/tNgHywvyZuCGnbH3ov49Z/6e8LPLRR4=
 tinygo.org/x/tinyterm v0.3.0 h1:4MMZoMyrbWbjru1KP/Z2TGhaguy/Uh5Mdhf/niemM8c=
 tinygo.org/x/tinyterm v0.3.0/go.mod h1:F1pQjxEwNZQIc5czeJSBtk57ucEvbR4u7vHaLhWhHtg=
diff --git a/uuid_sd.go b/uuid_sd.go
index b8b28fe..e9deb8b 100644
--- a/uuid_sd.go
+++ b/uuid_sd.go
@@ -10,9 +10,9 @@ import "unsafe"
 
 type shortUUID C.ble_uuid_t
 
-func (uuid UUID) shortUUID() (C.ble_uuid_t, uint32) {
+func (uuid UUID) shortUUID() (C.ble_uuid_t, C.uint32_t) {
 	var short C.ble_uuid_t
-	short.uuid = uint16(uuid[3])
+	short.uuid = C.uint16_t(uuid[3])
 	if uuid.Is16Bit() {
 		short._type = C.BLE_UUID_TYPE_BLE
 		return short, 0
@@ -24,7 +24,7 @@ func (uuid UUID) shortUUID() (C.ble_uuid_t, uint32) {
 // UUID returns the full length UUID for this short UUID.
 func (s shortUUID) UUID() UUID {
 	if s._type == C.BLE_UUID_TYPE_BLE {
-		return New16BitUUID(s.uuid)
+		return New16BitUUID(uint16(s.uuid))
 	}
 	var outLen C.uint8_t
 	var outUUID UUID