MCU temperature telemetry for companion

[yarda]

Repeaters show internal MCU temperature which can be handy, please add the same for companions.

[yarda]

I tried:

diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index 6fbb0f74..4e5abbfb 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -651,6 +651,12 @@ uint8_t MyMesh::onContactRequest(const ContactInfo &contact, uint32_t sender_tim
     if (permissions & TELEM_PERM_BASE) { // only respond if base permission bit is set
       telemetry.reset();
       telemetry.addVoltage(TELEM_CHANNEL_SELF, (float)board.getBattMilliVolts() / 1000.0f);
+
+      float temperature = board.getMCUTemperature();
+      if(!isnan(temperature)) { // Supported boards with built-in temperature sensor. ESP32-C3 may return NAN
+        telemetry.addTemperature(TELEM_CHANNEL_SELF, temperature); // Built-in MCU Temperature
+      }
+
       // query other sensors -- target specific
       sensors.querySensors(permissions, telemetry);
 
@@ -1636,6 +1642,10 @@ void MyMesh::handleCmdFrame(size_t len) {
   } else if (cmd_frame[0] == CMD_SEND_TELEMETRY_REQ && len == 4) {  // 'self' telemetry request
     telemetry.reset();
     telemetry.addVoltage(TELEM_CHANNEL_SELF, (float)board.getBattMilliVolts() / 1000.0f);
+    float temperature = board.getMCUTemperature();
+    if(!isnan(temperature)) { // Supported boards with built-in temperature sensor. ESP32-C3 may return NAN
+      telemetry.addTemperature(TELEM_CHANNEL_SELF, temperature); // Built-in MCU Temperature
+    }
     // query other sensors -- target specific
     sensors.querySensors(0xFF, telemetry);
}

But the board.getMCUTemperature(); call reboots the T114. No idea why.

[yarda]

Hmm, got it. The softdev watchdog is rebooting the device, the softdev API needs to be used:

diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index 6fbb0f74..a17b0bc2 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -1636,6 +1636,12 @@ void MyMesh::handleCmdFrame(size_t len) {
   } else if (cmd_frame[0] == CMD_SEND_TELEMETRY_REQ && len == 4) {  // 'self' telemetry request
     telemetry.reset();
     telemetry.addVoltage(TELEM_CHANNEL_SELF, (float)board.getBattMilliVolts() / 1000.0f);
+    uint32_t err_code;
+    int32_t temp;
+    err_code = sd_temp_get(&temp);
+    if (err_code == NRF_SUCCESS) {
+      telemetry.addTemperature(TELEM_CHANNEL_SELF, temp * 0.25f);
+    }
     // query other sensors -- target specific
     sensors.querySensors(0xFF, telemetry);