Modify UM980 firmware update path

Use LittleFS so that the UM980 can be updated regardless of resets or terminal open/close. Built on similar STM32 pass through technique.

Author: nseidle

Firmware/RTK_Everywhere/LoRa.ino

@@ -385,7 +385,7 @@ void removeUpdateLoraFirmware()
 
 // Force UART connection to LoRa radio for firmware update on the next boot by creating updateLoraFirmware.txt in
 // LittleFS
-bool forceLoRaPassthrough()
+bool createLoRaPassthrough()
 {
     if (online.fs == false)
         return false;

Firmware/RTK_Everywhere/UM980.ino

@@ -1149,3 +1149,148 @@ void um980MenuConstellations()
 }
 
 #endif // COMPILE_UM980
+
+// Check if updateUm980Firmware.txt exists
+bool checkUpdateUm980Firmware()
+{
+    if (online.fs == false)
+        return false;
+
+    if (LittleFS.exists("/updateUm980Firmware.txt"))
+    {
+        if (settings.debugGnss)
+            systemPrintln("LittleFS updateUm980Firmware.txt exists");
+
+        // We do not remove the file here. See removeupdateUm980Firmware().
+
+        return true;
+    }
+
+    return false;
+}
+
+void removeUpdateUm980Firmware()
+{
+    if (online.fs == false)
+        return;
+
+    if (LittleFS.exists("/updateUm980Firmware.txt"))
+    {
+        if (settings.debugGnss)
+            systemPrintln("Removing updateUm980Firmware.txt ");
+
+        LittleFS.remove("/updateUm980Firmware.txt");
+    }
+}
+
+// Force UART connection to UM980 for firmware update on the next boot by creating updateUm980Firmware.txt in
+// LittleFS
+bool createUm980Passthrough()
+{
+    if (online.fs == false)
+        return false;
+
+    if (LittleFS.exists("/updateUm980Firmware.txt"))
+    {
+        if (settings.debugGnss)
+            systemPrintln("LittleFS updateUm980Firmware.txt already exists");
+        return true;
+    }
+
+    File updateUm980Firmware = LittleFS.open("/updateUm980Firmware.txt", FILE_WRITE);
+    updateUm980Firmware.close();
+
+    if (LittleFS.exists("/updateUm980Firmware.txt"))
+        return true;
+
+    if (settings.debugGnss)
+        systemPrintln("Unable to create updateUm980Firmware.txt on LittleFS");
+    return false;
+}
+
+void beginUm980FirmwareUpdate()
+{
+    // Note: We cannot increase the bootloading speed beyond 115200 because
+    //  we would need to alter the UM980 baud, then save to NVM, then allow the UM980 to reset.
+    //  This is workable, but the next time the RTK Torch resets, it assumes communication at 115200bps
+    //  This fails and communication is broken. We could program in some logic that attempts comm at 460800
+    //  then reconfigures the UM980 to 115200bps, then resets, but autobaud detection in the UM980 library is
+    //  not yet supported.
+
+    // Stop all UART tasks
+    tasksStopGnssUart();
+
+    systemPrintln();
+    systemPrintln("Entering UM980 direct connect for firmware update and configuration. Disconnect this terminal "
+                  "connection. Use "
+                  "UPrecise to update the firmware. Baudrate: 115200bps. Press the power button to return "
+                  "to normal operation.");
+    systemFlush();
+
+    // Make sure ESP-UART1 is connected to UM980
+    muxSelectUm980();
+
+    if (serialGNSS == nullptr)
+        serialGNSS = new HardwareSerial(2); // Use UART2 on the ESP32 for communication with the GNSS module
+
+    serialGNSS->begin(115200, SERIAL_8N1, pin_GnssUart_RX, pin_GnssUart_TX);
+
+    // UPrecise needs to query the device before entering bootload mode
+    // Wait for UPrecise to send bootloader trigger (character T followed by character @) before resetting UM980
+    bool inBootMode = false;
+
+    // Echo everything to/from UM980
+    while (1)
+    {
+        // Data coming from UM980 to external USB
+        if (serialGNSS->available())
+            Serial.write(serialGNSS->read());
+
+        // Data coming from external USB to UM980
+        if (Serial.available())
+        {
+            byte incoming = Serial.read();
+            serialGNSS->write(incoming);
+
+            // Detect bootload sequence
+            if (inBootMode == false && incoming == 'T')
+            {
+                byte nextIncoming = Serial.peek();
+                if (nextIncoming == '@')
+                {
+                    // Reset UM980
+                    um980Reset();
+                    delay(25);
+                    um980Boot();
+
+                    inBootMode = true;
+                }
+            }
+        }
+
+        if (digitalRead(pin_powerButton) == HIGH)
+        {
+            while (digitalRead(pin_powerButton) == HIGH)
+                delay(100);
+
+            // Remove file and reset to exit pass-through mode
+            removeUpdateUm980Firmware();
+
+            // Beep to indicate exit
+            beepOn();
+            delay(300);
+            beepOff();
+            delay(100);
+            beepOn();
+            delay(300);
+            beepOff();
+
+            systemPrintln("Exiting UM980 passthrough mode");
+            systemFlush(); // Complete prints
+
+            ESP.restart();
+        }
+    }
+
+    systemFlush(); // Complete prints
+}

Firmware/RTK_Everywhere/menuSystem.ino

@@ -519,59 +519,16 @@ void menuDebugHardware()
         }
         else if (incoming == 13 && present.gnss_um980)
         {
-            // Note: We cannot increase the bootloading speed beyond 115200 because
-            //  we would need to alter the UM980 baud, then save to NVM, then allow the UM980 to reset.
-            //  This is workable, but the next time the RTK Torch resets, it assumes communication at 115200bps
-            //  This fails and communication is broken. We could program in some logic that attempts comm at 460800
-            //  then reconfigures the UM980 to 115200bps, then resets, but autobaud detection in the UM980 library is
-            //  not yet supported.
-
-            // Stop all UART tasks
-            tasksStopGnssUart();
-
-            systemPrintln("Entering UM980 direct connect at 115200bps for firmware update and configuration. Use "
-                          "UPrecise to update "
-                          "the firmware. Power cycle RTK Torch to "
-                          "return to normal operation.");
-
-            // Make sure ESP-UART1 is connected to UM980
-            digitalWrite(pin_muxA, LOW);
-
-            // UPrecise needs to query the device before entering bootload mode
-            // Wait for UPrecise to send bootloader trigger (character T followed by character @) before resetting UM980
-            bool inBootMode = false;
-
-            // Echo everything to/from UM980
-            while (1)
+            // Create a file in LittleFS
+            if (createUm980Passthrough() == true)
             {
-                // Data coming from UM980 to external USB
-                if (serialGNSS->available())
-                    systemWrite(serialGNSS->read());
-
-                // Data coming from external USB to UM980
-                if (systemAvailable())
-                {
-                    byte incoming = systemRead();
-                    serialGNSS->write(incoming);
-
-                    // Detect bootload sequence
-                    if (inBootMode == false && incoming == 'T')
-                    {
-                        byte nextIncoming = Serial.peek();
-                        if (nextIncoming == '@')
-                        {
-                            // Reset UM980
-                            um980Reset();
-                            delay(25);
-                            um980Boot();
+                systemPrintln();
+                systemPrintln("UM980 passthrough mode has been recorded to LittleFS. Device will now reset.");
+                systemFlush(); // Complete prints
 
-                            inBootMode = true;
-                        }
-                    }
-                }
+                ESP.restart();
             }
         }
-
         else if (incoming == 14)
         {
             settings.enablePsram ^= 1;
@@ -586,10 +543,10 @@ void menuDebugHardware()
         }
         else if (incoming == 17 && present.radio_lora)
         {
-            if (forceLoRaPassthrough() == true)
+            if (createLoRaPassthrough() == true)
             {
                 systemPrintln();
-                systemPrintln("Passthrough mode has been recorded to LittleFS. Device will now reset.");
+                systemPrintln("STM32 passthrough mode has been recorded to LittleFS. Device will now reset.");
                 systemFlush(); // Complete prints
 
                 ESP.restart();