Sending Data Between Arduino Nano and D1 Mini

Question

I am sending data from Arduino Nano to D1 Mini,

Transmitter is Arduino Nano

Transmitter Code:

#include <DES.h>
#include <SoftwareSerial.h>
SoftwareSerial link(2, 3); // Rx, Tx
DES des;
byte in[8];
String input;
char text[20];
char charVal[6];
char buf[30];
void setup() {
 link.begin(9600);
 Serial.begin(9600);
 Serial.println("Hello! Pleace Enter Your Data to Encrypt");
}
void tdesTest() {
 byte out[8];
 byte key[] = {
 0x3b, 0x38, 0x98, 0x37, 0x15, 0x20, 0xf7, 0x5e, // key A
 0x92, 0x2f, 0xb5, 0x10, 0xc7, 0x1f, 0x43, 0x6e, // key B
 0x3b, 0x38, 0x98, 0x37, 0x15, 0x20, 0xf7, 0x5e, // key C (in this case A)
 };
 Serial.println();
 Serial.println("====== Triple-DES test ======");
 //encrypt
 Serial.print("Encrypt...");
 unsigned long time = micros();
 des.tripleEncrypt(out, in, key);
 time = micros() - time;
 Serial.print("done. (");
 Serial.print(time);
 Serial.println(" micros)");
 delay(10000);
 printArray(out, link);
 link.write(out, 9);
 delay(2000);
 //decrypt
 for (int i = 0; i < 8; i++)
 {
 in[i] = out[i];
 }
 Serial.print("Decrypt...");
 time = micros();
 des.tripleDecrypt(out, in, key);
 time = micros() - time;
 Serial.print("done. (");
 Serial.print(time);
 Serial.println(" micros)");
 printArray(out);
 delay(2000);
}
//passing output and Print
void printArray(byte output[], Print& serial)
{
 for (int i = 0; i < 8; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 
 Serial.println();
}
//printing output without link pass
void printArray(byte output[])
{
 for (int i = 0; i < 8; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 Serial.println();
}
void userdata() {
 Serial.println("Sending User Data");
 byte user[] = {0x31,0x30,0x30,0x30,0x30,0x30,0x30,0x30};
 printArray(user, link);
 link.write(user, 9);
 delay(100);
 tdesTest();
 
}
void loop() {
 while (Serial.available() > 0) {
 String input = Serial.readString(); // read the incoming data as string
 memset(in, 0, 9); // Erase the contents of in[]
 input.toCharArray((char *)in, 9); // Copy up to 8 bytes from the string
 
 userdata();
 }
}

And receiving same from D1 Mini (ESP8266)

Receiver Code:

//Receiver code
#include <SoftwareSerial.h>
SoftwareSerial link(4, 0); // Rx, Tx
byte greenLED = 13;
byte cString[8];
byte chPos;
byte ch;
byte out[8];
String hexstring = "";
void setup()
{
 link.begin(9600); //setup software serial
 Serial.begin(9600); //setup serial monitor
 pinMode(greenLED, OUTPUT);
}
void loop()
{
 while (link.available() > 0)
 {
 ESP.wdtDisable(); // This helps th avoid not reciving data after second try 
 //read incoming char by char:
 ch = link.read();
 cString[chPos] = ch;
 chPos++;
 digitalWrite(greenLED, HIGH); //flash led to show data is arriving
 delay(20);
 digitalWrite(greenLED, LOW);
 }
 if (ch != 0)
 {
 printArray(cString);
 ESP.wdtEnable(1);
 Serial.flush();
 cString[chPos] = 0; //terminate cString
 chPos = 0;
 }
}
//printing output
void printArray(byte output[])
{
 for (int i = 0; i < 8; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 hexstring += String(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 Serial.println();
 Serial.println("Your String Sir:");
 Serial.print(hexstring);
 Serial.println();
 ch = 0; // Avoid printing 0s when no data is recived
 hexstring = ""; //Clear the memeory of hexstring
}

In Receiver I am receiving data as below:

enter image description here

I want to get data in Single Stream to receiver as Example: 31 30 30 30 30 30 30 30 7E B5 2D 4D 93 CB 08 BA or in receiver join two streams in to a single stream,

On Side Note: 1st Part is Plain Data and 2nd Part will be Encrypted Data

Could anyone please help..

• fabianoriccardi: Can't you concat 2 strings? If you would a white space between each byte just concatenate a space. Trivial answer but I'm not sure which your core question is.
• VinRocka: How to do that? Transmitter sends two char streams,
• VinRocka: Since I don't think concat will work
• fabianoriccardi: Why not? You calculate hexstring, which can be concat to the next one.
• VinRocka: Could you share me how in my receiver code ?

Answer 1

Managed Get it Working:

Change the Transmitter Code to Cascade Two Char Streams Before Sending:

Transmitter Code:

#include <DES.h>
#include <SoftwareSerial.h>
SoftwareSerial link(2, 3); // Rx, Tx
DES des;
byte in[8];
String input;
void setup() {
 link.begin(9600);
 Serial.begin(9600);
 Serial.println("Hello! Pleace Enter Your Data to Encrypt");
}
//passing output and Print
void printArray(byte output[], Print& serial)
{
 for (int i = 0; i < 8; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 Serial.println();
}
//printing output without link pass
void printArray(byte output[])
{
 for (int i = 0; i < 8; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 Serial.println();
}
void userdata_and_Encrypt() {
 Serial.println("Sending User Data");
 byte username[] = {0x31, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30};
 printArray(username, link);
 byte username_data = (username, 9);
 delay(100);
 byte out[8];
 byte key[] = {
 0x3b, 0x38, 0x98, 0x37, 0x15, 0x20, 0xf7, 0x5e, // key A
 0x92, 0x2f, 0xb5, 0x10, 0xc7, 0x1f, 0x43, 0x6e, // key B
 0x3b, 0x38, 0x98, 0x37, 0x15, 0x20, 0xf7, 0x5e, // key C (in this case A)
 };
 Serial.println();
 Serial.println("====== Triple-DES test ======");
 //encrypt
 Serial.print("Encrypt...");
 unsigned long time = micros();
 des.tripleEncrypt(out, in, key);
 time = micros() - time;
 Serial.print("done. (");
 Serial.print(time);
 Serial.println(" micros)");
 delay(100);
 printArray(out, link);
 byte password_data = (out, 9);
 delay(100);
 byte data_stream = username_data + password_data; 
 printArray(data_stream, link);
 link.write(out, 17);
 //decrypt
 for (int i = 0; i < 8; i++)
 {
 in[i] = out[i];
 }
 Serial.print("Decrypt...");
 time = micros();
 des.tripleDecrypt(out, in, key);
 time = micros() - time;
 Serial.print("done. (");
 Serial.print(time);
 Serial.println(" micros)");
 printArray(out);
 delay(100);
}
void loop() {
 while (Serial.available() > 0) {
 String input = Serial.readString(); // read the incoming data as string
 memset(in, 0, 9); // Erase the contents of in[]
 input.toCharArray((char *)in, 9); // Copy up to 8 bytes from the string
 userdata_and_Encrypt();
 }
}

Receiver Code to Accept 16 Bytes

Receiver Code:

//Receiver code
#include <SoftwareSerial.h>
SoftwareSerial link(4, 0); // Rx, Tx
byte greenLED = 13;
byte cString[8];
byte chPos;
byte ch;
byte out[8];
String hexstring = "";
static String data = "";
void setup()
{
 link.begin(9600); //setup software serial
 Serial.begin(9600); //setup serial monitor
 pinMode(greenLED, OUTPUT);
}
void loop()
{
 while (link.available() > 0)
 {
 ESP.wdtDisable(); // This helps th avoid not reciving data after second try
 //read incoming char by char:
 ch = link.read();
 cString[chPos] = ch;
 chPos++;
 digitalWrite(greenLED, HIGH); //flash led to show data is arriving
 delay(20);
 digitalWrite(greenLED, LOW);
 }
 if (ch != 0)
 {
 printArray(cString);
 ESP.wdtEnable(1);
 Serial.flush();
 cString[chPos] = 0; //terminate cString
 chPos = 0;
 }
}
//printing output
void printArray(byte output[])
{
 for (int i = 0; i < 16; i++)
 {
 if (output[i] < 0x10)
 {
 Serial.print("0");
 }
 Serial.print(output[i], HEX);
 hexstring += String(output[i], HEX);
 Serial.print(" ");
 delay(100);
 }
 Serial.println();
 Serial.println("Your String Sir:");
 Serial.println(hexstring);
 Serial.println();
 ch = 0; // Avoid printing 0s when no data is recived
 hexstring = ""; //Clear the memeory of hexstring
}

Working Output:

enter image description here