Diff: sm_qsl/dn_fsm.c

Revision:

0:8ca1e814a851

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sm_qsl/dn_fsm.c	Wed May 02 09:26:10 2018 +0000
@@ -0,0 +1,1352 @@
+/*
+Copyright (c) 2016, Dust Networks. All rights reserved.
+
+Finite State Machine for the QuickStart Library.
+
+\license See attached DN_LICENSE.txt.
+*/
+
+#include "dn_fsm.h"
+#include "dn_ipmt.h"
+#include "dn_time.h"
+#include "dn_watchdog.h"
+#include "dn_qsl_api.h"
+#include "dn_debug.h"
+
+//=========================== variables =======================================
+
+typedef struct
+{
+	// FSM
+	uint32_t fsmEventScheduled_ms;
+	uint16_t fsmDelay_ms;
+	bool fsmArmed;
+	uint8_t state;
+	// C Library API
+	dn_fsm_reply_cbt replyCb;
+	dn_fsm_timer_cbt fsmCb;
+	uint8_t replyBuf[MAX_FRAME_LENGTH];
+	uint8_t notifBuf[MAX_FRAME_LENGTH];
+	// Connection
+	uint8_t socketId;
+	uint16_t networkId;
+	uint8_t joinKey[DN_JOIN_KEY_LEN];
+	uint16_t srcPort;
+	uint32_t service_ms;
+	uint8_t payloadBuf[DN_DEFAULT_PAYLOAD_SIZE_LIMIT];
+	uint8_t payloadSize;
+	uint8_t destIPv6[DN_IPv6ADDR_LEN];
+	uint16_t destPort;
+	dn_inbox_t inbox;
+} dn_fsm_vars_t;
+
+static dn_fsm_vars_t dn_fsm_vars;
+
+
+//=========================== prototypes ======================================
+// FSM
+static void dn_fsm_run(void);
+static void dn_fsm_scheduleEvent(uint16_t delay, dn_fsm_timer_cbt cb);
+static void dn_fsm_cancelEvent(void);
+static void dn_fsm_setReplyCallback(dn_fsm_reply_cbt cb);
+static void dn_fsm_enterState(uint8_t newState, uint16_t spesificDelay);
+static bool dn_fsm_cmd_timeout(uint32_t cmdStart_ms, uint32_t cmdTimeout_ms);
+// C Library API
+static void dn_ipmt_notif_cb(uint8_t cmdId, uint8_t subCmdId);
+static void dn_ipmt_reply_cb(uint8_t cmdId);
+static void dn_event_responseTimeout(void);
+static void dn_event_reset(void);
+static void dn_reply_reset(void);
+static void dn_event_disconnect(void);
+static void dn_reply_disconnect(void);
+static void dn_event_getMoteStatus(void);
+static void dn_reply_getMoteStatus(void);
+static void dn_event_openSocket(void);
+static void dn_reply_openSocket(void);
+static void dn_event_bindSocket(void);
+static void dn_reply_bindSocket(void);
+static void dn_event_setJoinKey(void);
+static void dn_reply_setJoinKey(void);
+static void dn_event_setNetworkId(void);
+static void dn_reply_setNetworkId(void);
+static void dn_event_search(void);
+static void dn_reply_search(void);
+static void dn_event_join(void);
+static void dn_reply_join(void);
+static void dn_event_requestService(void);
+static void dn_reply_requestService(void);
+static void dn_event_getServiceInfo(void);
+static void dn_reply_getServiceInfo(void);
+static void dn_event_sendTo(void);
+static void dn_reply_sendTo(void);
+// helpers
+static dn_err_t checkAndSaveNetConfig(uint16_t netID, const uint8_t* joinKey, uint16_t srcPort, uint32_t req_service_ms);
+static uint8_t getPayloadLimit(uint16_t destPort);
+
+//=========================== public ==========================================
+
+//========== QSL API
+
+bool dn_qsl_init(void)
+{
+	//debug("QSL: Init");
+	// Reset local variables
+	memset(&dn_fsm_vars, 0, sizeof (dn_fsm_vars));
+
+	// Initialize the ipmt module
+	dn_ipmt_init // Should be augmented with return value to know if successful...
+			(
+			dn_ipmt_notif_cb,
+			dn_fsm_vars.notifBuf,
+			sizeof (dn_fsm_vars.notifBuf),
+			dn_ipmt_reply_cb
+			);
+
+	dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+	return TRUE;
+}
+
+bool dn_qsl_isConnected(void)
+{
+	//debug("QSL: isConnected");
+	return dn_fsm_vars.state == DN_FSM_STATE_CONNECTED;
+}
+
+bool dn_qsl_connect(uint16_t netID, const uint8_t* joinKey, uint16_t srcPort, uint32_t req_service_ms)
+{
+	uint32_t cmdStart_ms = dn_time_ms();
+	dn_err_t err;
+	//debug("QSL: Connect");
+	switch (dn_fsm_vars.state)
+	{
+	case DN_FSM_STATE_NOT_INITIALIZED:
+		//log_warn("Can't connect; not initialized");
+		return FALSE;
+	case DN_FSM_STATE_DISCONNECTED:
+		err = checkAndSaveNetConfig(netID, joinKey, srcPort, req_service_ms);
+		if (err != DN_ERR_NONE)
+		{
+			return FALSE;
+		}
+		//debug("Starting connect process...");
+		dn_fsm_enterState(DN_FSM_STATE_PRE_JOIN, 0);
+		break;
+	case DN_FSM_STATE_CONNECTED:
+		if ((netID > 0 && netID != dn_fsm_vars.networkId)
+				|| (joinKey != NULL && memcmp(joinKey, dn_fsm_vars.joinKey, DN_JOIN_KEY_LEN) != 0)
+				|| (srcPort > 0 && srcPort != dn_fsm_vars.srcPort))
+		{
+			err = checkAndSaveNetConfig(netID, joinKey, srcPort, req_service_ms);
+			if (err != DN_ERR_NONE)
+			{
+				return FALSE;
+			}
+			//debug("New network ID, join key and/or source port; reconnecting...");
+			dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		} else if (req_service_ms > 0 && req_service_ms != dn_fsm_vars.service_ms)
+		{
+			//debug("New service request");
+			dn_fsm_vars.service_ms = req_service_ms;
+			dn_fsm_enterState(DN_FSM_STATE_REQ_SERVICE, 0);
+		} else
+		{
+			//debug("Already connected");
+			// Nothing to do
+		}
+		break;
+	default:
+		//log_err("Unexpected state");
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		return FALSE;
+	}
+
+	// Drive FSM until connect success/failure or timeout
+	while (dn_fsm_vars.state != DN_FSM_STATE_CONNECTED
+			&& dn_fsm_vars.state != DN_FSM_STATE_DISCONNECTED
+			&& !dn_fsm_cmd_timeout(cmdStart_ms, DN_CONNECT_TIMEOUT_S * 1000))
+	{
+		dn_watchdog_feed();
+		dn_fsm_run();
+	}
+
+	return dn_fsm_vars.state == DN_FSM_STATE_CONNECTED;
+}
+
+bool dn_qsl_send(const uint8_t* payload, uint8_t payloadSize_B, uint16_t destPort)
+{
+	uint32_t cmdStart_ms = dn_time_ms();
+	uint8_t maxPayloadSize;
+	//debug("QSL: Send");
+	switch (dn_fsm_vars.state)
+	{
+	case DN_FSM_STATE_CONNECTED:
+		maxPayloadSize = getPayloadLimit(destPort);
+
+		if (payloadSize_B > maxPayloadSize)
+		{
+			//log_warn("Payload size (%u) exceeds limit (%u)", payloadSize_B, maxPayloadSize);
+			return FALSE;
+		}
+		// Store outbound payload and parameters
+		memcpy(dn_fsm_vars.payloadBuf, payload, payloadSize_B);
+		dn_fsm_vars.payloadSize = payloadSize_B;
+		memcpy(dn_fsm_vars.destIPv6, DN_DEST_IP, DN_IPv6ADDR_LEN);
+		dn_fsm_vars.destPort = (destPort > 0) ? destPort : DN_DEFAULT_DEST_PORT;
+		// Start send process
+		dn_fsm_enterState(DN_FSM_STATE_SENDING, 0);
+		break;
+	default:
+		//log_warn("Can't send; not connected");
+		return FALSE;
+	}
+
+	// Drive FSM until send success/failure or timeout
+	while (dn_fsm_vars.state == DN_FSM_STATE_SENDING
+			&& !dn_fsm_cmd_timeout(cmdStart_ms, DN_SEND_TIMEOUT_MS))
+	{
+		dn_watchdog_feed();
+		dn_fsm_run();
+	}
+
+	// Catch send failure
+	if (dn_fsm_vars.state == DN_FSM_STATE_SEND_FAILED)
+	{
+		//debug("Send failed");
+		dn_fsm_enterState(DN_FSM_STATE_CONNECTED, 0);
+		return FALSE;
+	}
+
+	return dn_fsm_vars.state == DN_FSM_STATE_CONNECTED;
+}
+
+uint8_t dn_qsl_read(uint8_t* readBuffer)
+{
+	uint8_t bytesRead = 0;
+	//debug("QSL: Read");
+	if (dn_fsm_vars.inbox.unreadPackets > 0)
+	{
+		// Pop payload at head of inbox
+		memcpy
+				(
+				readBuffer,
+				dn_fsm_vars.inbox.pktBuf[dn_fsm_vars.inbox.head],
+				dn_fsm_vars.inbox.pktSize[dn_fsm_vars.inbox.head]
+				);
+		bytesRead = dn_fsm_vars.inbox.pktSize[dn_fsm_vars.inbox.head];
+		dn_fsm_vars.inbox.head = (dn_fsm_vars.inbox.head + 1) % DN_INBOX_SIZE;
+		dn_fsm_vars.inbox.unreadPackets--;
+		//debug("Read %u bytes from inbox", bytesRead);
+	} else
+	{
+		//debug("Inbox empty");
+	}
+	return bytesRead;
+}
+
+//=========================== private =========================================
+
+//========== FSM
+
+//===== run
+
+/**
+ Check if an event is scheduled and run it if due.
+ */
+static void dn_fsm_run(void)
+{
+	uint32_t timePassed_ms = dn_time_ms() - dn_fsm_vars.fsmEventScheduled_ms; // Handle dn_time_ms wrap around
+	if (dn_fsm_vars.fsmArmed && (timePassed_ms > dn_fsm_vars.fsmDelay_ms))
+	{
+		// Scheduled event is due; execute it
+		dn_fsm_vars.fsmArmed = FALSE;
+		if (dn_fsm_vars.fsmCb != NULL)
+		{
+			dn_fsm_vars.fsmCb();
+		}
+	} else
+	{
+		// Sleep to save CPU power
+		dn_sleep_ms(DN_FSM_RUN_INTERVAL_MS);
+	}
+}
+
+//===== scheduleEvent
+
+/**
+ Schedule function to be called after a given delay.
+ */
+static void dn_fsm_scheduleEvent(uint16_t delay_ms, dn_fsm_timer_cbt cb)
+{
+	dn_fsm_vars.fsmEventScheduled_ms = dn_time_ms();
+	dn_fsm_vars.fsmDelay_ms = delay_ms;
+	dn_fsm_vars.fsmCb = cb;
+	dn_fsm_vars.fsmArmed = TRUE;
+}
+
+//===== cancelEvent
+
+/**
+ Cancel currently scheduled event.
+ */
+static void dn_fsm_cancelEvent(void)
+{
+	dn_fsm_vars.fsmDelay_ms = 0;
+	dn_fsm_vars.fsmCb = NULL;
+	dn_fsm_vars.fsmArmed = FALSE;
+}
+
+//===== setReplyCallback
+
+/**
+ Set the callback function that the C Library will execute when the next reply
+ is received and the reply buffer is ready to be parsed.
+ */
+static void dn_fsm_setReplyCallback(dn_fsm_reply_cbt cb)
+{
+	dn_fsm_vars.replyCb = cb;
+}
+
+//===== enterState
+
+/**
+ Transition FSM to new state and schedule any default entry events.
+ */
+static void dn_fsm_enterState(uint8_t newState, uint16_t spesificDelay)
+{
+	uint32_t now = dn_time_ms();
+	uint16_t delay = DN_CMD_PERIOD_MS;
+	static uint32_t lastTransition = 0;
+	if (lastTransition == 0)
+		lastTransition = now;
+
+	// Use default delay if none given
+	if (spesificDelay > 0)
+		delay = spesificDelay;
+
+	// Schedule default events for transition into states
+	switch (newState)
+	{
+	case DN_FSM_STATE_PRE_JOIN:
+		dn_fsm_scheduleEvent(delay, dn_event_getMoteStatus);
+		break;
+	case DN_FSM_STATE_PROMISCUOUS:
+		dn_fsm_scheduleEvent(delay, dn_event_search);
+		break;
+	case DN_FSM_STATE_JOINING:
+		dn_fsm_scheduleEvent(delay, dn_event_join);
+		break;
+	case DN_FSM_STATE_REQ_SERVICE:
+		dn_fsm_scheduleEvent(delay, dn_event_requestService);
+		break;
+	case DN_FSM_STATE_RESETTING:
+		if (DN_MOTE_DISCONNECT_BEFORE_RESET)
+			dn_fsm_scheduleEvent(delay, dn_event_disconnect); // More graceful
+		else
+			dn_fsm_scheduleEvent(delay, dn_event_reset); // Faster
+		break;
+	case DN_FSM_STATE_SENDING:
+		/*
+		 Send is scheduled immediately because it is the users responsibility
+		 to implement the necessary backoff and not exceed the granted bandwidth.
+		 */
+		dn_fsm_scheduleEvent(0, dn_event_sendTo);
+		break;
+	case DN_FSM_STATE_SEND_FAILED:
+	case DN_FSM_STATE_DISCONNECTED:
+	case DN_FSM_STATE_CONNECTED:
+		// These states have no default entry events
+		break;
+	default:
+		//log_warn("Attempt at entering unexpected state %#.2x", newState);
+		return;
+	}
+
+	//debug("FSM state transition: %#.2x --> %#.2x (%u ms)",
+			//dn_fsm_vars.state, newState, (uint32_t)(now - lastTransition));
+	lastTransition = now;
+	dn_fsm_vars.state = newState;
+}
+
+//===== cmdTimeout
+
+/**
+ Correctly abort the current API command if time passed since the given start
+ has exceeded the given timeout.
+ */
+static bool dn_fsm_cmd_timeout(uint32_t cmdStart_ms, uint32_t cmdTimeout_ms)
+{
+	uint32_t timePassed_ms = dn_time_ms() - cmdStart_ms; // Handle dn_time_ms wrap around
+	bool timeout = timePassed_ms > cmdTimeout_ms;
+	if (timeout)
+	{
+		// Cancel any ongoing transmission or scheduled event and reset reply cb
+		dn_ipmt_cancelTx();
+		dn_fsm_vars.replyCb = NULL;
+		dn_fsm_cancelEvent();
+
+		// Default timeout state is different while connecting vs sending
+		switch (dn_fsm_vars.state)
+		{
+		case DN_FSM_STATE_PRE_JOIN:
+		case DN_FSM_STATE_JOINING:
+		case DN_FSM_STATE_REQ_SERVICE:
+		case DN_FSM_STATE_RESETTING:
+			//debug("Connect timeout");
+			dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+			break;
+		case DN_FSM_STATE_SENDING:
+			//debug("Send timeout");
+			dn_fsm_enterState(DN_FSM_STATE_SEND_FAILED, 0);
+			break;
+		default:
+			//log_err("Command timeout in unexpected state: %#x", dn_fsm_vars.state);
+			break;
+		}
+	}
+	return timeout;
+}
+
+//========== C Library API
+
+//===== notif_cb
+
+/**
+ This function is called whenever a notification is received through the
+ SmartMesh C Library. The notification variables are than available through
+ the notification buffer that can be cast to the correct type based on the
+ given command ID (notification type).
+ */
+static void dn_ipmt_notif_cb(uint8_t cmdId, uint8_t subCmdId)
+{
+	//dn_ipmt_timeIndication_nt* notif_timeIndication;
+	dn_ipmt_events_nt* notif_events;
+	dn_ipmt_receive_nt* notif_receive;
+	//dn_ipmt_macRx_nt* notif_macRx;
+	//dn_ipmt_txDone_nt* notif_txDone;
+	dn_ipmt_advReceived_nt* notif_advReceived;
+
+	//debug("Got notification: cmdId; %#.2x (%u), subCmdId; %#.2x (%u)",
+			//cmdId, cmdId, subCmdId, subCmdId);
+
+	switch (cmdId)
+	{
+	case CMDID_TIMEINDICATION:
+		// Not implemented
+		break;
+	case CMDID_EVENTS:
+		notif_events = (dn_ipmt_events_nt*)dn_fsm_vars.notifBuf;
+		//debug("State: %#.2x | Events: %#.4x", notif_events->state, notif_events->events);
+
+		// Check if in fsm state where we expect a certain mote event
+		switch (dn_fsm_vars.state)
+		{
+		case DN_FSM_STATE_JOINING:
+			if (notif_events->events & DN_MOTE_EVENT_MASK_OPERATIONAL)
+			{
+				// Join complete
+				if (dn_fsm_vars.service_ms > 0)
+				{
+					dn_fsm_enterState(DN_FSM_STATE_REQ_SERVICE, 0);
+				} else
+				{
+					dn_fsm_enterState(DN_FSM_STATE_CONNECTED, 0);
+				}
+				return;
+			}
+			break;
+		case DN_FSM_STATE_REQ_SERVICE:
+			if (notif_events->events & DN_MOTE_EVENT_MASK_SVC_CHANGE)
+			{
+				// Service request complete; check what we were granted
+				dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_getServiceInfo);
+				return;
+			}
+			break;
+		}
+
+		// Check if reported mote state should trigger fsm state transition
+		switch (notif_events->state)
+		{
+		case DN_MOTE_STATE_IDLE:
+			switch (dn_fsm_vars.state)
+			{
+			case DN_FSM_STATE_PRE_JOIN:
+			case DN_FSM_STATE_JOINING:
+			case DN_FSM_STATE_REQ_SERVICE:
+			case DN_FSM_STATE_RESETTING:
+			case DN_FSM_STATE_PROMISCUOUS:
+				// Restart during connect; retry
+				dn_fsm_enterState(DN_FSM_STATE_PRE_JOIN, 0);
+				break;
+			case DN_FSM_STATE_CONNECTED:
+			case DN_FSM_STATE_SENDING:
+			case DN_FSM_STATE_SEND_FAILED:
+				// Disconnect/reset; set state accordingly
+				dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+				break;
+			}
+			break;
+		case DN_MOTE_STATE_OPERATIONAL:
+			switch (dn_fsm_vars.state)
+			{
+			case DN_FSM_STATE_PRE_JOIN:
+			case DN_FSM_STATE_PROMISCUOUS:
+				/*
+				 Early (and unexpected) operational (connected to network)
+				 during connect; reset and retry
+				 */
+				dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+				break;
+			}
+			break;
+		}
+		break;
+	case CMDID_RECEIVE:
+		notif_receive = (dn_ipmt_receive_nt*)dn_fsm_vars.notifBuf;
+		//debug("Received downstream data");
+
+		// Push payload at tail of inbox
+		memcpy
+				(
+				dn_fsm_vars.inbox.pktBuf[dn_fsm_vars.inbox.tail],
+				notif_receive->payload,
+				notif_receive->payloadLen
+				);
+		dn_fsm_vars.inbox.pktSize[dn_fsm_vars.inbox.tail] = notif_receive->payloadLen;
+		dn_fsm_vars.inbox.tail = (dn_fsm_vars.inbox.tail + 1) % DN_INBOX_SIZE;
+		if(dn_fsm_vars.inbox.unreadPackets == DN_INBOX_SIZE)
+		{
+			//log_warn("Inbox overflow; oldest packet dropped");
+		} else
+		{
+			dn_fsm_vars.inbox.unreadPackets++;
+		}
+		//debug("Inbox capacity at %u / %u", dn_fsm_vars.inbox.unreadPackets, DN_INBOX_SIZE);
+
+		break;
+	case CMDID_MACRX:
+		// Not implemented
+		break;
+	case CMDID_TXDONE:
+		// Not implemented
+		break;
+	case CMDID_ADVRECEIVED:
+		notif_advReceived = (dn_ipmt_advReceived_nt*)dn_fsm_vars.notifBuf;
+		//debug("Received network advertisement");
+
+		if (dn_fsm_vars.state == DN_FSM_STATE_PROMISCUOUS
+				&& dn_fsm_vars.networkId == DN_PROMISCUOUS_NET_ID)
+		{
+			//debug("Saving network ID: %#.4x (%u)",
+					//notif_advReceived->netId, notif_advReceived->netId);
+			dn_fsm_vars.networkId = notif_advReceived->netId;
+			dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_setNetworkId);
+		}
+
+		break;
+	default:
+		//log_warn("Unknown notification ID");
+		break;
+	}
+}
+
+//===== reply_cb
+
+/**
+ This function is called whenever a reply is received through the SmartMesh.
+ C Library. It calls the reply function that was armed at the start of the
+ current event.
+ */
+static void dn_ipmt_reply_cb(uint8_t cmdId)
+{
+	//debug("Got reply: cmdId; %#.2x (%u)", cmdId, cmdId);
+	if (dn_fsm_vars.replyCb == NULL)
+	{
+		//debug("Reply callback empty");
+		return;
+	}
+	dn_fsm_vars.replyCb();
+}
+
+//===== response_timeout
+
+/**
+ This event is scheduled after each mote API command is sent, effectively
+ placing a timeout for the mote to reply.
+ */
+static void dn_event_responseTimeout(void)
+{
+	//debug("Response timeout");
+
+	// Cancel any ongoing transmission and reset reply cb
+	dn_ipmt_cancelTx();
+	dn_fsm_vars.replyCb = NULL;
+
+	switch (dn_fsm_vars.state)
+	{
+	case DN_FSM_STATE_PRE_JOIN:
+	case DN_FSM_STATE_JOINING:
+	case DN_FSM_STATE_REQ_SERVICE:
+	case DN_FSM_STATE_RESETTING:
+	case DN_FSM_STATE_PROMISCUOUS:
+		// Response timeout during connect; retry
+		dn_fsm_enterState(DN_FSM_STATE_PRE_JOIN, 0);
+		break;
+	case DN_FSM_STATE_SENDING:
+		// Response timeout during send; fail
+		dn_fsm_enterState(DN_FSM_STATE_SEND_FAILED, 0);
+		break;
+	default:
+		//log_err("Response timeout in unexpected state: %#x", dn_fsm_vars.state);
+		break;
+	}
+}
+
+//===== reset
+
+/**
+ Initiates a soft-reset of the mote. Its reply simply checks that
+ the command was accepted, as the FSM will wait for the ensuing boot event.
+ */
+static void dn_event_reset(void)
+{
+	//debug("Reset");
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_reset);
+
+	// Issue mote API command
+	dn_ipmt_reset
+			(
+			(dn_ipmt_reset_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_reset(void)
+{
+	dn_ipmt_reset_rpt* reply;
+	//debug("Reset reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_reset_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Mote soft-reset initiated");
+		// Will wait for notification of reboot
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== disconnect
+
+/**
+ This event does much the same as reset, however it uses the disconnect command
+ instead, where the mote first spends a couple of seconds notifying its
+ neighbors of its imminent soft-reset. If the reply is anything but success,
+ it will schedule a simple reset event instead.
+ */
+static void dn_event_disconnect(void)
+{
+	//debug("Disconnect");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_disconnect);
+
+	// Issue mote API command
+	dn_ipmt_disconnect
+			(
+			(dn_ipmt_disconnect_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_disconnect(void)
+{
+	dn_ipmt_disconnect_rpt* reply;
+	//debug("Disconnect reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_disconnect_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Mote disconnect initiated");
+		// Will wait for notification of reboot
+		break;
+	case DN_RC_INVALID_STATE:
+		//debug("The mote is in an invalid state to disconnect; resetting");
+		dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_reset);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_reset);
+		break;
+	}
+}
+
+//===== getMoteStatus
+
+/**
+ Asks the mote for its status, and the reply will use the reported
+ mote state to decide whether or not it is ready to proceed with pre-join
+ configurations or if a reset is needed first.
+ */
+static void dn_event_getMoteStatus(void)
+{
+	//debug("Mote status");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_getMoteStatus);
+
+	// Issue mote API command
+	dn_ipmt_getParameter_moteStatus
+			(
+			(dn_ipmt_getParameter_moteStatus_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_getMoteStatus(void)
+{
+	dn_ipmt_getParameter_moteStatus_rpt* reply;
+	//debug("Mote status reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_getParameter_moteStatus_rpt*)dn_fsm_vars.replyBuf;
+	//debug("Mote state: %#.2x", reply->state);
+
+	// Choose next event or state transition
+	switch (reply->state)
+	{
+	case DN_MOTE_STATE_IDLE:
+		dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_openSocket);
+		break;
+	case DN_MOTE_STATE_OPERATIONAL:
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	default:
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	}
+}
+
+//===== openSocket
+
+/**
+ Tells the mote to open a socket, and the reply saves the reported
+ socket ID before scheduling its binding. If no sockets are available, a mote
+ reset is scheduled and the connect process starts over.
+ */
+static void dn_event_openSocket(void)
+{
+	//debug("Open socket");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_openSocket);
+
+	// Issue mote API command
+	dn_ipmt_openSocket
+			(
+			DN_PROTOCOL_TYPE_UDP,
+			(dn_ipmt_openSocket_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_openSocket(void)
+{
+	dn_ipmt_openSocket_rpt* reply;
+	//debug("Open socket reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_openSocket_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Socket %d opened successfully", reply->socketId);
+		dn_fsm_vars.socketId = reply->socketId;
+		dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_bindSocket);
+		break;
+	case DN_RC_NO_RESOURCES:
+		//debug("Couldn't create socket due to resource availability");
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== bindSocket
+
+/**
+ Binds the previously opened socket to a port. If said port is already bound,
+ a mote reset is scheduled and the connect process starts over.
+ */
+static void dn_event_bindSocket(void)
+{
+	//debug("Bind socket");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_bindSocket);
+
+	// Issue mote API command
+	dn_ipmt_bindSocket
+			(
+			dn_fsm_vars.socketId,
+			dn_fsm_vars.srcPort,
+			(dn_ipmt_bindSocket_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_bindSocket(void)
+{
+	dn_ipmt_bindSocket_rpt* reply;
+	//debug("Bind socket reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_bindSocket_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Socket bound successfully");
+		dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_setJoinKey);
+		break;
+	case DN_RC_BUSY:
+		//debug("Port already bound");
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	case DN_RC_NOT_FOUND:
+		//debug("Invalid socket ID");
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== setJoinKey
+
+/**
+ Configures the join key that the mote should use when attempting to join a
+ network.
+ */
+static void dn_event_setJoinKey(void)
+{
+	//debug("Set join key");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_setJoinKey);
+
+	// Issue mote API command
+	dn_ipmt_setParameter_joinKey
+			(
+			dn_fsm_vars.joinKey,
+			(dn_ipmt_setParameter_joinKey_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_setJoinKey(void)
+{
+	dn_ipmt_setParameter_joinKey_rpt* reply;
+	//debug("Set join key reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_setParameter_joinKey_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Join key set");
+		if (dn_fsm_vars.networkId == DN_PROMISCUOUS_NET_ID)
+		{
+			// Promiscuous netID set; search for new first
+			dn_fsm_enterState(DN_FSM_STATE_PROMISCUOUS, 0);
+			/*
+			 As of version 1.4.x, a network ID of 0xFFFF can be used to indicate
+			 that the mote should join the first network heard. Thus, searching
+			 before joining will not be necessary.
+			*/
+		} else
+		{
+			dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_setNetworkId);
+		}
+		break;
+	case DN_RC_WRITE_FAIL:
+		//debug("Could not write the key to storage");
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== setNetworkId
+
+/**
+ Configures the ID of the network that the mote should should try to join.
+ */
+static void dn_event_setNetworkId(void)
+{
+	//debug("Set network ID");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_setNetworkId);
+
+	// Issue mote API command
+	dn_ipmt_setParameter_networkId
+			(
+			dn_fsm_vars.networkId,
+			(dn_ipmt_setParameter_networkId_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_setNetworkId(void)
+{
+	dn_ipmt_setParameter_networkId_rpt* reply;
+	//debug("Set network ID reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_setParameter_networkId_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Network ID set");
+		dn_fsm_enterState(DN_FSM_STATE_JOINING, 0);
+		break;
+	case DN_RC_WRITE_FAIL:
+		//debug("Could not write the network ID to storage");
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== search
+
+/**
+ Tells the mote to start listening for network advertisements. The mote will
+ then report the network ID (among other things) of any advertisements heard.
+ Upon a successful reply, the FSM will wait for an advReceived notification,
+ before attempting to join the reported network.
+ */
+static void dn_event_search(void)
+{
+	//debug("Search");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_search);
+
+	// Issue mote API command
+	dn_ipmt_search
+			(
+			(dn_ipmt_search_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_search(void)
+{
+	dn_ipmt_search_rpt* reply;
+	//debug("Search reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_search_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Searching for network advertisements");
+		// Will wait for notification of advertisement received
+		break;
+	case DN_RC_INVALID_STATE:
+		//debug("The mote is in an invalid state to start searching");
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== join
+
+/**
+ Requests that the mote start searching for the previously configured network
+ and attempt to join with the configured join key. If the mote is in an invalid
+ state to join or lacks configuration to start joining, a reset is scheduled and
+ the connect procedure starts over. Otherwise the FSM will wait for the ensuing
+ operational event when the mote has finished joining.
+ */
+static void dn_event_join(void)
+{
+	//debug("Join");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_join);
+
+	// Issue mote API command
+	dn_ipmt_join
+			(
+			(dn_ipmt_join_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_join(void)
+{
+	dn_ipmt_join_rpt* reply;
+	//debug("Join reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_join_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Join operation started");
+		// Will wait for join complete notification (operational event)
+		break;
+	case DN_RC_INVALID_STATE:
+		//debug("The mote is in an invalid state to start join operation");
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	case DN_RC_INCOMPLETE_JOIN_INFO:
+		//debug("Incomplete configuration to start joining");
+		dn_fsm_enterState(DN_FSM_STATE_RESETTING, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== requestService
+
+/**
+ The mote is told to request a new service level from the manager. Its reply
+ simply checks that the command was accepted, as the FSM will wait for the
+ ensuing svcChange event when the service allocation has changed.
+ */
+static void dn_event_requestService(void)
+{
+	//debug("Request service");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_requestService);
+
+	// Issue mote API command
+	dn_ipmt_requestService
+			(
+			DN_SERVICE_ADDRESS,
+			DN_SERVICE_TYPE_BW,
+			dn_fsm_vars.service_ms,
+			(dn_ipmt_requestService_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_requestService(void)
+{
+	dn_ipmt_requestService_rpt* reply;
+	//debug("Request service reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_requestService_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Service request accepted");
+		// Will wait for svcChanged notification
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== getServiceInfo
+
+/**
+ Requests details about the service currently allocated to the mote. Its reply
+ checks that we have been granted a service equal to or better than what was
+ requested (smaller value equals better).
+ */
+static void dn_event_getServiceInfo(void)
+{
+	//debug("Get service info");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_getServiceInfo);
+
+	// Issue mote API command
+	dn_ipmt_getServiceInfo
+			(
+			DN_SERVICE_ADDRESS,
+			DN_SERVICE_TYPE_BW,
+			(dn_ipmt_getServiceInfo_rpt*)dn_fsm_vars.replyBuf
+			);
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_getServiceInfo(void)
+{
+	dn_ipmt_getServiceInfo_rpt* reply;
+	//debug("Get service info reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_getServiceInfo_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		if (reply->state == DN_SERVICE_STATE_COMPLETED)
+		{
+			if (reply->value <= dn_fsm_vars.service_ms)
+			{
+				//debug("Granted service of %u ms (requested %u ms)", reply->value, dn_fsm_vars.service_ms);
+				dn_fsm_enterState(DN_FSM_STATE_CONNECTED, 0);
+			} else
+			{
+				//log_warn("Only granted service of %u ms (requested %u ms)", reply->value, dn_fsm_vars.service_ms);
+				dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+			}
+
+		} else
+		{
+			//debug("Service request still pending");
+			dn_fsm_scheduleEvent(DN_CMD_PERIOD_MS, dn_event_getServiceInfo);
+		}
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_DISCONNECTED, 0);
+		break;
+	}
+}
+
+//===== sendTo
+
+/**
+ This event sends a packet into the network, and its reply checks that it was
+ accepted and queued up for transmission.
+ */
+static void dn_event_sendTo(void)
+{
+	dn_err_t err;
+	//debug("Send");
+
+	// Arm reply callback
+	dn_fsm_setReplyCallback(dn_reply_sendTo);
+
+	// Issue mote API command
+	err = dn_ipmt_sendTo
+			(
+			dn_fsm_vars.socketId,
+			dn_fsm_vars.destIPv6,
+			dn_fsm_vars.destPort,
+			DN_SERVICE_TYPE_BW,
+			DN_PACKET_PRIORITY_MEDIUM,
+			DN_PACKET_ID_NO_NOTIF,
+			dn_fsm_vars.payloadBuf,
+			dn_fsm_vars.payloadSize,
+			(dn_ipmt_sendTo_rpt*)dn_fsm_vars.replyBuf
+			);
+	if (err != DN_ERR_NONE)
+	{
+		//debug("Send error: %u", err);
+		dn_fsm_enterState(DN_FSM_STATE_SEND_FAILED, 0);
+	}
+
+	// Schedule timeout for reply
+	dn_fsm_scheduleEvent(DN_SERIAL_RESPONSE_TIMEOUT_MS, dn_event_responseTimeout);
+}
+
+static void dn_reply_sendTo(void)
+{
+	dn_ipmt_sendTo_rpt* reply;
+	//debug("Send reply");
+
+	// Cancel reply timeout
+	dn_fsm_cancelEvent();
+
+	// Parse reply
+	reply = (dn_ipmt_sendTo_rpt*)dn_fsm_vars.replyBuf;
+
+	// Choose next event or state transition
+	switch (reply->RC)
+	{
+	case DN_RC_OK:
+		//debug("Packet was queued up for transmission");
+		dn_fsm_enterState(DN_FSM_STATE_CONNECTED, 0);
+		break;
+	case DN_RC_NO_RESOURCES:
+		//debug("No queue space to accept the packet");
+		dn_fsm_enterState(DN_FSM_STATE_SEND_FAILED, 0);
+		break;
+	default:
+		//log_warn("Unexpected response code: %#x", reply->RC);
+		dn_fsm_enterState(DN_FSM_STATE_SEND_FAILED, 0);
+		break;
+	}
+}
+
+//=========================== helpers =========================================
+
+static dn_err_t checkAndSaveNetConfig(uint16_t netID, const uint8_t* joinKey, uint16_t srcPort, uint32_t req_service_ms)
+{
+	if (netID == 0)
+	{
+		//debug("No network ID given; using default");
+		dn_fsm_vars.networkId = DN_DEFAULT_NET_ID;
+	} else if (netID == DN_PROMISCUOUS_NET_ID)
+	{
+		//debug("Promiscuous network ID given; will search for and join first network advertised");
+		dn_fsm_vars.networkId = netID;
+	} else
+	{
+		dn_fsm_vars.networkId = netID;
+	}
+
+	if (joinKey == NULL)
+	{
+		//debug("No join key given; using default");
+		memcpy(dn_fsm_vars.joinKey, DN_DEFAULT_JOIN_KEY, DN_JOIN_KEY_LEN);
+	} else
+	{
+		memcpy(dn_fsm_vars.joinKey, joinKey, DN_JOIN_KEY_LEN);
+	}
+
+	if (srcPort == 0)
+	{
+		//debug("No source port given; using default");
+		dn_fsm_vars.srcPort = DN_DEFAULT_SRC_PORT;
+	} else
+	{
+		dn_fsm_vars.srcPort = srcPort;
+	}
+
+	if (req_service_ms == 0)
+	{
+		//debug("No service requested; will only be granted base bandwidth");
+	}
+	dn_fsm_vars.service_ms = req_service_ms;
+
+	return DN_ERR_NONE;
+}
+
+static uint8_t getPayloadLimit(uint16_t destPort)
+{
+	bool destIsF0Bx = (destPort >= DN_WELL_KNOWN_PORT_1 && destPort <= DN_WELL_KNOWN_PORT_8);
+	bool srcIsF0Bx = (dn_fsm_vars.srcPort >= DN_WELL_KNOWN_PORT_1 && dn_fsm_vars.srcPort <= DN_WELL_KNOWN_PORT_8);
+	int8_t destIsMng = memcmp(DN_DEST_IP, DN_DEFAULT_DEST_IP, DN_IPv6ADDR_LEN);
+
+	if (destIsMng == 0)
+	{
+		if (destIsF0Bx && srcIsF0Bx)
+			return DN_PAYLOAD_SIZE_LIMIT_MNG_HIGH;
+		else if (destIsF0Bx || srcIsF0Bx)
+			return DN_PAYLOAD_SIZE_LIMIT_MNG_MED;
+		else
+			return DN_PAYLOAD_SIZE_LIMIT_MNG_LOW;
+	} else
+	{
+		if (destIsF0Bx && srcIsF0Bx)
+			return DN_PAYLOAD_SIZE_LIMIT_IP_HIGH;
+		else if (destIsF0Bx || srcIsF0Bx)
+			return DN_PAYLOAD_SIZE_LIMIT_IP_MED;
+		else
+			return DN_PAYLOAD_SIZE_LIMIT_IP_LOW;
+	}
+}
+