Record the NTP request arrival time - without interrupts

Author: PaulZC

Firmware/RTK_Everywhere/Begin.ino

@@ -778,7 +778,6 @@ void beginFS()
 }
 
 // Check if configureViaEthernet.txt exists
-// Used to indicate if SparkFun_WebServer_ESP32_W5500 needs _exclusive_ access to SPI and interrupts
 bool checkConfigureViaEthernet()
 {
     if (online.fs == false)
@@ -796,7 +795,6 @@ bool checkConfigureViaEthernet()
 }
 
 // Force configure-via-ethernet mode by creating configureViaEthernet.txt in LittleFS
-// Used to indicate if SparkFun_WebServer_ESP32_W5500 needs _exclusive_ access to SPI and interrupts
 bool forceConfigureViaEthernet()
 {
     if (online.fs == false)
@@ -836,8 +834,6 @@ void beginInterrupts()
     {
         DMW_if systemPrintf("pin_Ethernet_Interrupt: %d\r\n", pin_Ethernet_Interrupt);
         pinMode(pin_Ethernet_Interrupt, INPUT); // Prepare the interrupt pin
-        // TODO: figure out how to handle NTP mode and timestamp the arrival of UDP NTP requests
-        // attachInterrupt(pin_Ethernet_Interrupt, ethernetISR, FALLING); // Attach the interrupt
     }
 #endif // COMPILE_ETHERNET
 }

Firmware/RTK_Everywhere/Ethernet.ino

@@ -208,6 +208,7 @@ bool ethernetIsNeeded()
     return needed;
 }
 
+/*
 // Ethernet (W5500) ISR
 // Triggered by the falling edge of the W5500 interrupt signal - indicates the arrival of a packet
 // Record the time the packet arrived
@@ -218,6 +219,7 @@ void ethernetISR()
     // Do it in updateEthernet
     gettimeofday((timeval *)&ethernetNtpTv, nullptr); // Record the time of the NTP interrupt
 }
+*/
 
 // Restart the Ethernet controller
 void ethernetRestart()
@@ -393,7 +395,7 @@ void onEthernetEvent(arduino_event_id_t event, arduino_event_info_t info)
 // Web server routines
 //=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 
-// Start Ethernet WebServer ESP32 W5500 - needs exclusive access to WiFi, SPI and Interrupts
+// Start Ethernet for the web server
 void ethernetWebServerStartESP32W5500()
 {
     Network.onEvent(onEthernetEvent);
@@ -405,10 +407,10 @@ void ethernetWebServerStartESP32W5500()
         ETH.config(settings.ethernetIP, settings.ethernetGateway, settings.ethernetSubnet, settings.ethernetDNS);
 }
 
-// Stop the Ethernet web server
+// Stop Ethernet for the web server
 void ethernetWebServerStopESP32W5500()
 {
-    ETH.end(); // This is _really_ important. It undoes the low-level changes to SPI and interrupts
+    ETH.end();
 }
 
 #endif // COMPILE_ETHERNET

Firmware/RTK_Everywhere/NTP.ino

@@ -78,8 +78,6 @@ const RtkMode_t ntpServerMode = RTK_MODE_NTP;
 
 static NetworkUDP *ntpServer; // This will be instantiated when we know the NTP port
 static uint8_t ntpServerState;
-static volatile uint8_t
-    ntpSockIndex; // The W5500 socket index for NTP - so we can enable and read the correct interrupt
 static uint32_t lastLoggedNTPRequest;
 
 //----------------------------------------
@@ -474,7 +472,7 @@ struct NTPpacket
 
 // =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 // NTP process one request
-// recTv contains the timeval the NTP packet was received - from the W5500 interrupt
+// recTv contains the timeval the NTP packet was received
 // syncTv contains the timeval when the RTC was last sync'd
 // ntpDiag will contain useful diagnostics
 bool ntpProcessOneRequest(bool process, const timeval *recTv, const timeval *syncTv, char *ntpDiag = nullptr,
@@ -486,19 +484,24 @@ bool ntpProcessOneRequest(bool process, const timeval *recTv, const timeval *syn
     if (ntpDiag != nullptr)
         *ntpDiag = 0; // Clear any existing diagnostics
 
-    int packetDataSize = ntpServer->parsePacket();
+    gettimeofday((timeval *)&ethernetNtpTv, nullptr); // Record the possible time of the NTP request
 
-    IPAddress remoteIP = ntpServer->remoteIP();
-    uint16_t remotePort = ntpServer->remotePort();
+    int packetDataSize = 0;
 
-    if (ntpDiag != nullptr) // Add the packet size and remote IP/Port to the diagnostics
-    {
-        snprintf(ntpDiag, ntpDiagSize, "NTP request from:  Remote IP: %d.%d.%d.%d  Remote Port: %d\r\n", remoteIP[0],
-                 remoteIP[1], remoteIP[2], remoteIP[3], remotePort);
-    }
+    if (ntpServer->available() > 0)
+        packetDataSize = ntpServer->parsePacket();
 
-    if (packetDataSize && (packetDataSize >= NTPpacket::NTPpacketSize))
+    if (packetDataSize >= NTPpacket::NTPpacketSize)
     {
+        IPAddress remoteIP = ntpServer->remoteIP();
+        uint16_t remotePort = ntpServer->remotePort();
+
+        if (ntpDiag != nullptr) // Add the packet size and remote IP/Port to the diagnostics
+        {
+            snprintf(ntpDiag, ntpDiagSize, "NTP request from:  Remote IP: %d.%d.%d.%d  Remote Port: %d\r\n", remoteIP[0],
+                    remoteIP[1], remoteIP[2], remoteIP[3], remotePort);
+        }
+
         // Read the NTP packet
         NTPpacket packet;
 
@@ -774,7 +777,6 @@ void ntpServerStop()
     // Release the NTP server memory
     if (ntpServer)
     {
-        w5500DisableSocketInterrupt(ntpSockIndex); // Disable the receive interrupt
         ntpServer->stop();
         delete ntpServer;
         ntpServer = nullptr;
@@ -850,12 +852,7 @@ void ntpServerUpdate()
                 ntpServerStop();
             else
             {
-                // Start the NTP server
-                // TODO
-                //ntpServer->begin(settings.ethernetNtpPort);
-                //ntpSockIndex = ntpServer->getSockIndex(); // Get the socket index
-                //w5500ClearSocketInterrupts();             // Clear all interrupts
-                //w5500EnableSocketInterrupt(ntpSockIndex); // Enable the RECV interrupt for the desired socket index
+                ntpServer->begin(settings.ethernetNtpPort); // Start the NTP server
                 online.ethernetNTPServer = true;
                 if (!inMainMenu)
                     reportHeapNow(settings.debugNtp);
@@ -872,9 +869,6 @@ void ntpServerUpdate()
 
         else
         {
-            if (w5500CheckSocketInterrupt(ntpSockIndex))
-                w5500ClearSocketInterrupt(ntpSockIndex); // Clear the socket interrupt here
-
             // Check for new NTP requests - if the time has been sync'd
             bool processed = ntpProcessOneRequest(systemState == STATE_NTPSERVER_SYNC, (const timeval *)&ethernetNtpTv,
                                                   (const timeval *)&gnssSyncTv, ntpDiag, sizeof(ntpDiag));

Firmware/RTK_Everywhere/RTK_Everywhere.ino

@@ -788,8 +788,9 @@ correctionsSource pplCorrectionsSource = CORR_NUM; // Record which source is fee
 
 // configureViaEthernet:
 //  Set to true if configureViaEthernet.txt exists in LittleFS.
-//  Causes setup and loop to skip any code which would cause SPI or interrupts to be initialized.
-//  This is to allow SparkFun_WebServer_ESP32_W5500 to have _exclusive_ access to WiFi, SPI and Interrupts.
+//  Previously, the SparkFun_WebServer_ESP32_W5500 needed _exclusive_ access to SPI and Interrupts.
+//  That's no longer true - thanks to Espressif adding full support for the W5500 within the
+//  arduino-esp32 core (v3.0.0+). But it's easier to leave the code as it is.
 bool configureViaEthernet;
 
 int floatLockRestarts;
@@ -1106,7 +1107,7 @@ void setup()
     gnssBeginPPS(); // Configure the time pulse output
 
     DMW_b("beginInterrupts");
-    beginInterrupts(); // Begin the TP and W5500 interrupts
+    beginInterrupts(); // Begin the TP interrupts
 
     DMW_b("beginButtons");
     beginButtons(); // Start task for button monitoring.

Firmware/RTK_Everywhere/States.ino

@@ -617,8 +617,6 @@ void stateUpdate()
             RTK_MODE(RTK_MODE_ETHERNET_CONFIG);
             // The code should only be able to enter this state if configureViaEthernet is true.
             // If configureViaEthernet is not true, we need to restart again.
-            //(If we continue, startEthernerWebServerESP32W5500 will fail as it won't have exclusive access to SPI and
-            // ints).
             if (!configureViaEthernet)
             {
                 displayConfigViaEthStarting(1500);