fix(openthread): Improves commentaries and code

libraries/OpenThread/examples/COAP/coap_lamp/coap_lamp.ino

@@ -93,15 +93,17 @@ void setupNode() {
 // this function is used by the Lamp mode to listen for CoAP frames from the Switch Node
 void otCOAPListen() {
   // waits for the client to send a CoAP request
-  char cliResp[256];
+  char cliResp[256] = {0};
   size_t len = OThreadCLI.readBytesUntil('\n', cliResp, sizeof(cliResp));
-  cliResp[len] = '\0';
+  cliResp[len - 1] = '\0';
   if (strlen(cliResp)) {
     String sResp(cliResp);
+    // cliResp shall be something like:
+    // "coap request from fd0c:94df:f1ae:b39a:ec47:ec6d:15e8:804a PUT with payload: 30"
+    // payload may be 30 or 31 (HEX) '0' or '1' (ASCII)
     log_d("Msg[%s]", cliResp);
     if (sResp.startsWith("coap request from") && sResp.indexOf("PUT") > 0) {
-      uint16_t payloadIdx = sResp.indexOf("payload: ") + 10;  // 0x30 | 0x31
-      char payload = sResp.charAt(payloadIdx);
+      char payload = sResp.charAt(sResp.length() - 1);  //  last character in the payload
       log_i("CoAP PUT [%s]\r\n", payload == '0' ? "OFF" : "ON");
       if (payload == '0') {
         for (int16_t c = 248; c > 16; c -= 8) {
@@ -127,6 +129,7 @@ void setup() {
   OThreadCLI.begin(false); // No AutoStart is necessary
   OThreadCLI.setTimeout(250); // waits 250ms for the OpenThread CLI response
   setupNode();
+  // LED goes Green when all is ready and Red when failed.
 }
 
 void loop() {

libraries/OpenThread/examples/COAP/coap_switch/coap_switch.ino

@@ -67,7 +67,7 @@ bool otDeviceSetup(const char **otSetupCmds, uint8_t nCmds1, const char **otCoap
     return false;
   }
   Serial.println("OpenThread setup done. Node is ready.");
-  // all fine! LED goes Blue
+  // all fine! LED goes and stays Blue
   neopixelWrite(RGB_BUILTIN, 0, 0, 64);   // BLUE ... Swtich is ready!
   return true;
 }
@@ -96,23 +96,24 @@ bool otCoapPUT(bool lampState) {
   coapMsg += OT_COAP_RESOURCE_NAME;
   coapMsg += " con 0";
 
+  // final command is "coap put ff05::abcd Lamp con 1" or "coap put ff05::abcd Lamp con 0"
   if (lampState) {
     coapMsg[coapMsg.length() - 1] = '1';
   }
   OThreadCLI.println(coapMsg.c_str());
   log_d("Send CLI CMD:[%s]", coapMsg.c_str());
 
   char cliResp[256];
-  // waits for the CoAP confirmation and Done message for about 5 seconds
+  // waits for the CoAP confirmation and Done message for about 1.25 seconds
   // timeout is based on Stream::setTimeout()
+  // Example of the expected confirmation response: "coap response from fdae:3289:1783:5c3f:fd84:c714:7e83:6122"
   uint8_t tries = 5;
   *cliResp = '\0';
   while (tries && !(gotDone && gotConfirmation)) {
     size_t len = OThreadCLI.readBytesUntil('\n', cliResp, sizeof(cliResp));
-    cliResp[len] = '\0';
+    cliResp[len - 1] = '\0';
     log_d("Try[%d]::MSG[%s]", tries, cliResp);
     if (strlen(cliResp)) {
-      log_d("%s", cliResp);
       if (!strncmp(cliResp, "coap response from", 18)) {
         gotConfirmation = true;
       }
@@ -132,13 +133,12 @@ bool otCoapPUT(bool lampState) {
 void checkUserButton() {
   static long unsigned int lastPress = 0;
   const long unsigned int debounceTime = 500;
-  static bool lastLampState = false;
+  static bool lastLampState = true; // first button press will turn the Lamp OFF from inital Green 
 
   pinMode(USER_BUTTON, INPUT_PULLUP); // C6/H2 User Button
   if (millis() > lastPress + debounceTime && digitalRead(USER_BUTTON) == LOW) {
-    if (otCoapPUT(!lastLampState)) {
-      lastLampState = !lastLampState;
-    } else {
+    lastLampState = !lastLampState;
+    if (!otCoapPUT(lastLampState)) { // failed: Lamp Node is not responding due to be off or unreachable
       // timeout from the CoAP PUT message... restart the node.
       neopixelWrite(RGB_BUILTIN, 255, 0, 0);  // RED ... something failed!
       Serial.println("Reseting the Node as Switch... wait.");
@@ -156,6 +156,7 @@ void setup() {
   OThreadCLI.begin(false); // No AutoStart is necessary
   OThreadCLI.setTimeout(250); // waits 250ms for the OpenThread CLI response
   setupNode();
+  // LED goes and keeps Blue when all is ready and Red when failed.
 }
 
 void loop() {

libraries/OpenThread/examples/SimpleCLI/SimpleCLI.ino

@@ -1,6 +1,6 @@
 /*
- * OpenThread.begin(false) will not start a node in a Thread Network
- * You will need to start it manually using the OpenThread CLI commands
+ * OpenThread.begin(false) will not automatically start a node in a Thread Network
+ * The user will need to start it manually using the OpenThread CLI commands
  * Use the Serial Monitor to interact with the OpenThread CLI
  * 
  * Type 'help' for a list of commands.

libraries/OpenThread/examples/SimpleThreadNetwork/LeaderNode/LeaderNode.ino

@@ -1,7 +1,7 @@
 /*
- * OpenThread.begin(false) will not start a node in a Thread Network
- * A Leader node is the first device to start Thread that has a complete dataset
- * This is achieved by using the OpenThread CLI command "dataset init new"
+ * OpenThread.begin(false) will not automatically start a node in a Thread Network
+ * A Leader node is the first device, that has a complete dataset, to start Thread
+ * A complete dataset is easily achieved by using the OpenThread CLI command "dataset init new"
  * 
  * In order to allow other node to join the network, 
  * all of them shall use the same network master key

libraries/OpenThread/examples/SimpleThreadNetwork/RouterNode/RouterNode.ino

@@ -1,6 +1,6 @@
 /*
- * OpenThread.begin(false) will not start a node in a Thread Network
- * A Router/Child node is the device that will join an existent Thread Network 
+ * OpenThread.begin(false) will not automatically start a node in a Thread Network
+ * A Router/Child node is the device that will join an existing Thread Network 
  * 
  * In order to allow this node to join the network, 
  * it shall use the same network master key as used by the Leader Node