add a new SERIAL psm state, to ensure device doesn't sleep while

connected to the phone over USB.

In support of

https://github.com/meshtastic/Meshtastic-Android/issues/38

docs/software/power.md

@@ -36,6 +36,10 @@ From lower to higher power consumption.
   onEntry: setBluetoothOn(true), screen.setOn(true)
   onExit: screen.setOn(false)
 
+- serial API usage (SERIAL) - Screen is on, device doesn't sleep, bluetooth off
+  onEntry: setBluetooth off, screen on
+  onExit:
+
 ## Behavior
 
 ### events that increase CPU activity
@@ -51,9 +55,11 @@ From lower to higher power consumption.
 - While in DARK/ON: If we receive EVENT_BLUETOOTH_PAIR we transition to ON and start our screen_on_secs timeout
 - While in NB/DARK/ON: If we receive EVENT_NODEDB_UPDATED we transition to ON (so the new screen can be shown)
 - While in DARK: While the phone talks to us over BLE (EVENT_CONTACT_FROM_PHONE) reset any sleep timers and stay in DARK (needed for bluetooth sw update and nice user experience if the user is reading/replying to texts)
+- while in LS/NB/DARK: if SERIAL_CONNECTED, go to serial
 
 ### events that decrease cpu activity
 
+- While in SERIAL: if SERIAL_DISCONNECTED, go to NB
 - While in ON: If PRESS event occurs, reset screen_on_secs timer and tell the screen to handle the pess
 - While in ON: If it has been more than screen_on_secs since a press, lower to DARK
 - While in DARK: If time since last contact by our phone exceeds phone_timeout_secs (15 minutes), we transition down into NB mode

src/PowerFSM.cpp

@@ -104,6 +104,12 @@ static void darkEnter()
     screen.setOn(false);
 }
 
+static void serialEnter()
+{
+    setBluetoothEnable(false);
+    screen.setOn(true);
+}
+
 static void onEnter()
 {
     screen.setOn(true);
@@ -133,6 +139,7 @@ State stateSDS(sdsEnter, NULL, NULL, "SDS");
 State stateLS(lsEnter, lsIdle, lsExit, "LS");
 State stateNB(nbEnter, NULL, NULL, "NB");
 State stateDARK(darkEnter, NULL, NULL, "DARK");
+State stateSERIAL(serialEnter, NULL, NULL, "SERIAL");
 State stateBOOT(bootEnter, NULL, NULL, "BOOT");
 State stateON(onEnter, NULL, NULL, "ON");
 Fsm powerFSM(&stateBOOT);
@@ -148,7 +155,7 @@ void PowerFSM_setup()
 
     powerFSM.add_transition(&stateNB, &stateNB, EVENT_RECEIVED_PACKET, NULL, "Received packet, resetting win wake");
 
-    // Handle press events
+    // Handle press events - note: we ignore button presses when in API mode
     powerFSM.add_transition(&stateLS, &stateON, EVENT_PRESS, NULL, "Press");
     powerFSM.add_transition(&stateNB, &stateON, EVENT_PRESS, NULL, "Press");
     powerFSM.add_transition(&stateDARK, &stateON, EVENT_PRESS, NULL, "Press");
@@ -160,6 +167,7 @@ void PowerFSM_setup()
     powerFSM.add_transition(&stateNB, &stateSDS, EVENT_LOW_BATTERY, NULL, "LowBat");
     powerFSM.add_transition(&stateDARK, &stateSDS, EVENT_LOW_BATTERY, NULL, "LowBat");
     powerFSM.add_transition(&stateON, &stateSDS, EVENT_LOW_BATTERY, NULL, "LowBat");
+    powerFSM.add_transition(&stateSERIAL, &stateSDS, EVENT_LOW_BATTERY, NULL, "LowBat");
 
     powerFSM.add_transition(&stateDARK, &stateON, EVENT_BLUETOOTH_PAIR, NULL, "Bluetooth pairing");
     powerFSM.add_transition(&stateON, &stateON, EVENT_BLUETOOTH_PAIR, NULL, "Bluetooth pairing");
@@ -173,6 +181,13 @@ void PowerFSM_setup()
     powerFSM.add_transition(&stateDARK, &stateON, EVENT_RECEIVED_TEXT_MSG, NULL, "Received text");
     powerFSM.add_transition(&stateON, &stateON, EVENT_RECEIVED_TEXT_MSG, NULL, "Received text"); // restarts the sleep timer
 
+    powerFSM.add_transition(&stateLS, &stateSERIAL, EVENT_SERIAL_CONNECTED, NULL, "serial API");
+    powerFSM.add_transition(&stateNB, &stateSERIAL, EVENT_SERIAL_CONNECTED, NULL, "serial API");
+    powerFSM.add_transition(&stateDARK, &stateSERIAL, EVENT_SERIAL_CONNECTED, NULL, "serial API");
+    powerFSM.add_transition(&stateON, &stateSERIAL, EVENT_SERIAL_CONNECTED, NULL, "serial API");
+
+    powerFSM.add_transition(&stateSERIAL, &stateNB, EVENT_SERIAL_DISCONNECTED, NULL, "serial disconnect");
+
     powerFSM.add_transition(&stateDARK, &stateDARK, EVENT_CONTACT_FROM_PHONE, NULL, "Contact from phone");
 
     powerFSM.add_transition(&stateNB, &stateDARK, EVENT_PACKET_FOR_PHONE, NULL, "Packet for phone");

src/PowerFSM.h

@@ -14,6 +14,8 @@
 #define EVENT_NODEDB_UPDATED 8     // NodeDB has a big enough change that we think you should turn on the screen
 #define EVENT_CONTACT_FROM_PHONE 9 // the phone just talked to us over bluetooth
 #define EVENT_LOW_BATTERY 10 // Battery is critically low, go to sleep
+#define EVENT_SERIAL_CONNECTED 11
+#define EVENT_SERIAL_DISCONNECTED 12
 
 extern Fsm powerFSM;
 

src/SerialConsole.cpp

@@ -1,6 +1,6 @@
 #include "SerialConsole.h"
+#include "PowerFSM.h"
 #include "configuration.h"
-#include "target_specific.h"
 #include <Arduino.h>
 
 #define Port Serial
@@ -40,5 +40,9 @@ void SerialConsole::handleToRadio(const uint8_t *buf, size_t len)
 /// Hookable to find out when connection changes
 void SerialConsole::onConnectionChanged(bool connected)
 {
-    setBluetoothEnable(!connected); // To prevent user confusion, turn off bluetooth while using the serial port api
+    if (connected) { // To prevent user confusion, turn off bluetooth while using the serial port api
+        powerFSM.trigger(EVENT_SERIAL_CONNECTED);
+    } else {
+        powerFSM.trigger(EVENT_SERIAL_DISCONNECTED);
+    }
 }

src/mesh/PhoneAPI.cpp

@@ -18,7 +18,7 @@ void PhoneAPI::init()
 void PhoneAPI::checkConnectionTimeout()
 {
     if (isConnected) {
-        bool newConnected = (millis() - lastContactMsec < radioConfig.preferences.phone_timeout_secs);
+        bool newConnected = (millis() - lastContactMsec < radioConfig.preferences.phone_timeout_secs * 1000L);
         if (!newConnected) {
             isConnected = false;
             onConnectionChanged(isConnected);
@@ -247,8 +247,9 @@ void PhoneAPI::handleToRadioPacket(MeshPacket *p) {}
 /// If the mesh service tells us fromNum has changed, tell the phone
 int PhoneAPI::onNotify(uint32_t newValue)
 {
-    checkConnectionTimeout(); // a handy place to check if we've heard from the phone (since the BLE version doesn't call this from idle)
-    
+    checkConnectionTimeout(); // a handy place to check if we've heard from the phone (since the BLE version doesn't call this
+                              // from idle)
+
     if (state == STATE_SEND_PACKETS || state == STATE_LEGACY) {
         DEBUG_MSG("Telling client we have new packets %u\n", newValue);
         onNowHasData(newValue);