Hello!
I am trying to place a float variable that has been painfully converted from a String, into an array, and then calling the array again so that I could retrieve the value.
Why am I going in such a roundabout way? well the hardware is a pain, and I could not think of any other way.
Hardware I am using is the M5Stack Core and the LoRa modules that are made for it. I have a pair of them so that they are able to talk to each other.
I can concur that the sending end has no issues, and it’s mostly on the receiving end. I am also uploading data on to thingspeak.
So far, I have noticed that I am constantly receiving 5 outputs, or at least, 5 lines of converted values. I tried pushing them into an array and extracting only the last as it is the relevant data but to no avail.
#include <M5Stack.h>
#include <M5LoRa.h>
#include "ThingSpeak.h"
#include "secrets.h"
#include <WiFi.h>
char ssid[] = SECRET_SSID; // your network SSID (name)
char pass[] = SECRET_PASS; // your network password
int keyIndex = 0; // your network key Index number (needed only for WEP)
WiFiClient client;
unsigned long myChannelNumber = SECRET_CH_ID;
const char * myWriteAPIKey = SECRET_WRITE_APIKEY;
int number = 0;
String outgoing; // outgoing message
byte msgCount = 0; // count of outgoing messages
byte localAddress = 0xFF; // address of this device
byte destination = 0xBB; // destination to send to
long lastSendTime = 0; // last send time
int interval = 1000; // interval between sends
void setup() {
Serial.begin(115200); //Initialize serial
WiFi.mode(WIFI_STA);
ThingSpeak.begin(client); // Initialize ThingSpeak
M5.begin();
while (!Serial);
Serial.println("LoRa Duplex B");
// Connect or reconnect to WiFi
/*if(WiFi.status() != WL_CONNECTED){
Serial.print("Attempting to connect to SSID: ");
Serial.println(SECRET_SSID);
while(WiFi.status() != WL_CONNECTED){
WiFi.begin(ssid, pass); // Connect to WPA/WPA2 network. Change this line if using open or WEP network
Serial.print(".");
delay(5000);
}
Serial.println("\nConnected.");
M5.Lcd.clear(BLACK);
}*/
// override the default CS, reset, and IRQ pins (optional)
LoRa.setPins();// set CS, reset, IRQ pin
if (!LoRa.begin(433E6)) { // initialize ratio at 915 MHz
Serial.println("LoRa init failed. Check your connections.");
while (true); // if failed, do nothing
}
Serial.println("LoRa init succeeded.");
}
void loop() {
/*if (millis() - lastSendTime > interval) {
String message = "Data Received"; // send a message
sendMessage(message);
Serial.println("Sending " + message);
M5.Lcd.setTextColor(BLUE);
M5.Lcd.println("Sending " + message);
lastSendTime = millis(); // timestamp the message
interval = random(1000) + 500; // 2-3 seconds
}*/
// parse for a packet, and call onReceive with the result:
onReceive(LoRa.parsePacket());
if(M5.BtnA.wasPressed()){
M5.Lcd.setCursor(0, 0);
M5.Lcd.clear(BLACK);
}
if(M5.BtnB.wasPressed()){
reinit();
}
M5.update();
}
void reinit(){
Serial.println("LoRa Duplex Reinitialization");
// override the default CS, reset, and IRQ pins (optional)
LoRa.setPins();// set CS, reset, IRQ pin
if (!LoRa.begin(433E6)) { // initialize ratio at 915 MHz
Serial.println("LoRa init failed. Check your connections.");
M5.Lcd.setCursor(0, 0);
M5.Lcd.setTextColor(RED);
M5.Lcd.println("Init failed!!!");
while (true); // if failed, do nothing
}
Serial.println("LoRa init succeeded.");
}
void sendMessage(String outgoing) {
LoRa.beginPacket(); // start packet
LoRa.write(destination); // add destination address
LoRa.write(localAddress); // add sender address
LoRa.write(msgCount); // add message ID
LoRa.write(outgoing.length()); // add payload length
LoRa.print(outgoing); // add payload
LoRa.endPacket(); // finish packet and send it
msgCount++; // increment message ID
}
void onReceive(int packetSize) {
float tempflt;
if (packetSize == 0) return; // if there's no packet, return
// read packet header bytes:
int recipient = LoRa.read(); // recipient address
byte sender = LoRa.read(); // sender address
byte incomingMsgId = LoRa.read(); // incoming msg ID
byte incomingLength = LoRa.read(); // incoming msg length
String incoming = "";
while (LoRa.available()) {
incoming += (char)LoRa.read();
M5.Lcd.setCursor(0,0);
M5.Lcd.setTextColor(YELLOW, BLACK);
M5.Lcd.setTextSize(2.5);
M5.Lcd.printf("TMP Rcv: %f \r", tempflt);
if (incomingLength == 5)
{
char icmgarray[incoming.length() + 1];
incoming.toCharArray(icmgarray, sizeof(icmgarray));
tempflt = atof(icmgarray);
Serial.println(tempflt);
//float tempfltarray[] = {tempflt};
//Serial.println(tempfltarray[5]);
}
// Write to ThingSpeak. There are up to 8 fields in a channel, allowing you to store up to 8 different
// pieces of information in a channel. Here, we write to field 1.
/*int x = ThingSpeak.writeField(myChannelNumber, 1, tempflt, myWriteAPIKey);
if(x == 200){
Serial.println("Channel update successful.");
M5.Lcd.setCursor(0,50);
M5.Lcd.setTextSize(2.0);
M5.Lcd.printf("TMP Rcv2: %s \r", tempflt);
}
else{
Serial.println("Problem updating channel. HTTP error code " + String(x));
}
delay(20000);*/
}
if (incomingLength != incoming.length()) { // check length for error
Serial.println("error: message length does not match length");
return; // skip rest of function
}
// if the recipient isn't this device or broadcast,
if (recipient != localAddress && recipient != 0xFF) {
Serial.println("This message is not for me.");
return; // skip rest of function
}
// if message is for this device, or broadcast, print details:
/*Serial.println("Received from: 0x" + String(sender, HEX));
Serial.println("Sent to: 0x" + String(recipient, HEX));
Serial.println("Message ID: " + String(incomingMsgId));
Serial.println("Message length: " + String(incomingLength));
Serial.println("Message: " + incoming);
Serial.println("RSSI: " + String(LoRa.packetRssi()));
M5.Lcd.println("RSSI: " + String(LoRa.packetRssi()));
Serial.println("Snr: " + String(LoRa.packetSnr()));
Serial.println();
/*M5.Lcd.setTextColor(YELLOW);
M5.Lcd.println("Message: " + incoming);*/
}
This is the whole code.
and this is the portion of the code that I am having the most trouble with.
oid onReceive(int packetSize) {
float tempflt;
if (packetSize == 0) return; // if there's no packet, return
// read packet header bytes:
int recipient = LoRa.read(); // recipient address
byte sender = LoRa.read(); // sender address
byte incomingMsgId = LoRa.read(); // incoming msg ID
byte incomingLength = LoRa.read(); // incoming msg length
String incoming = "";
while (LoRa.available()) {
incoming += (char)LoRa.read();
M5.Lcd.setCursor(0,0);
M5.Lcd.setTextColor(YELLOW, BLACK);
M5.Lcd.setTextSize(2.5);
M5.Lcd.printf("TMP Rcv: %f \r", tempflt);
if (incomingLength == 5)
{
char icmgarray[incoming.length() + 1];
incoming.toCharArray(icmgarray, sizeof(icmgarray));
tempflt = atof(icmgarray);
Serial.println(tempflt);
//float tempfltarray[] = {tempflt};
//Serial.println(tempfltarray[5]);
}
// Write to ThingSpeak. There are up to 8 fields in a channel, allowing you to store up to 8 different
// pieces of information in a channel. Here, we write to field 1.
/*int x = ThingSpeak.writeField(myChannelNumber, 1, tempflt, myWriteAPIKey);
if(x == 200){
Serial.println("Channel update successful.");
M5.Lcd.setCursor(0,50);
M5.Lcd.setTextSize(2.0);
M5.Lcd.printf("TMP Rcv2: %s \r", tempflt);
}
else{
Serial.println("Problem updating channel. HTTP error code " + String(x));
}
delay(20000);*/
}
The image that I attached is the output I am currently getting through the Serial monitor.
If anyone has any ideas, please, do tell! I’m hitting a bottleneck and I am struggling. Thanks!
