Remote Serial Terminal Connectivity From Anywhere DT-06 WiFi

1/*This is an Example of a Serial Command-response interface.
2  Arduino's  Serial data can be transparently carried over Wifi using a DT-06 (or ESP8266-01)
3  Wifi Modules are loaded with esp-link firmware
4  BLE (HM-10) wireless links  also work well.
5  
6  Check Baud on the WifI module is set to match this program
7  
8  Tested using excellent Android 'Serial WiFI Terminal' and 'Serial Bluetooth  Apps' by Kai Moriche.
9  
10  Sending a '?' +(CRLF) character will cause the  Arduino to display a list of serial menu options
11  Sending a 'L 1' Turns the  Nanos onboard LED On,  L 2 turns it Off (COMMANDS USE CAPITAL LETTERS)
12  Sending  'W 23' would save a new Temperature setting of 23 to the EEPROM
13  
14  Dated  : 10th Jam 2020
15  V1.01
16
17 Hardware //////////////////////////////////////////////////////////////////////////
18
19    This code uses the main serial port of the Arduino - shared by the USB socket  on a Nano.
20    When programming you MUST disconnect the DT-06 Wifi module connected  to Tx & Rx to avoid data conflicts 
21    For the Demo, Power the Arduino from  its 5V pins or use a USB 'power only' source.
22*/
23
24
25
26#include <EEPROM.h>       //1024 Byte EEPROM
27
28byte  LED = 13;          //The Nano's on-board  LED
29int Volts_ADC = A1;      //We will display volts on A1 when requested
30
31float  Volts = 0;
32byte TempSet = 0;        //Illustrating a non volatile setting configured  via the serial connection
33
34unsigned long msec = 0;
35unsigned long Lastmsec  = 0;
36unsigned long UpdateInterval = 1000;
37boolean OutputData = false;
38
39//Variables  used in Serial CLI and Message Parsing
40const byte numChars = 30;                 //  Maximum Char length of received serial messages terminated in a Linefeed.
41char  receivedChars[numChars];
42char RxdSerialMessage[numChars] = {0};    // variables  to hold the parsed data
43
44int RxdInt1 = 0;
45int RxdInt2 = 0;
46float RxdFloat2  = 0;    // Option to receive and use float values within command strings
47int  RxdInt3 = 0;
48int RxdInt4 = 0;
49int RxdInt5 = 0;
50char CommandChar = 0;
51boolean  NewData = false;
52
53
54
55//************************************ MAIN PROGRAM  START - SETUP *******************************
56void setup()
57{
58
59  Serial.begin(9600);       // Configue Hardware Serial. 
60  Serial.flush();           // Clears the  Serial RX buffer
61
62  TempSet = EEPROM.read(2);     //Reads a saved setup value  from EEPROM address location 2
63
64  pinMode(LED, OUTPUT);
65  digitalWrite(LED,  LOW);  //Set Nanos onboard LED initially off
66
67
68}
69
70//***********************************  MAIN PROGRAM LOOP **************************************
71void loop()
72{
73
74  SerialRxWithEndMarker();           //Check for data message in serial buffer
75                                     //messages seperated by NewLine char
76
77  if (NewData == true) {
78    parseData();                 // Function to Split  message into command and space seperated values
79    //showParsedData();          //  FOR TEST ONLY! see what Character command and values are received
80
81    HandleCommand();             //Routine to identify & manage different received command characters
82  }
83
84  msec = millis();                                // We use the millis  millisecond runtime counter to schedule specific tasks
85
86  if ((msec - Lastmsec)  > UpdateInterval) {       //The Code below is executed evert MPPT update interval  - 100ms)
87
88    if (OutputData == true) {
89      Serial.print(F("Volts on  A1 = "));
90      Serial.print(0.004887 * analogRead(Volts_ADC));    // read the  Volts input A1
91      Serial.println("Volts");
92    }
93
94    Lastmsec  = msec;
95
96  }
97}
98
99//****************************PROGRAM MAIN LOOP END  ************************************
100//****************************SUBROUTINES  FOLLOW ***************************************
101
102void HandleCommand (void)
103//  The first character within a received serial message (from SerialRxWithEndMarker  CR/LF) is extracted by the ParseData Subroutine
104// this routine identifies and  handles the specific command request.
105{
106
107  switch (CommandChar) {
108
109    case '?':                  // receiving a ? character will display the Serial  Terminal command Menu
110
111      ClearTerminal ();
112
113      Serial.println(F("Serial  Command Response Demo V1.0"));
114      Serial.println(F("--- Command list: ---"));
115      Serial.println("");
116      Serial.println(F("? -  Show this Menu!"));
117      Serial.println(F("V -  Stream A1 Voltage"));
118      Serial.println(F("L  -  Control LED"));
119      Serial.println(F("S -  Show Rxd message 'S 123 -456  54 67'etc"));
120      Serial.print(F("W -  Set Limit"));
121      Serial.print(F("  (Currently "));
122      Serial.print(TempSet);
123      Serial.println(F("°C  )"));
124      break;
125
126
127    case 'V':                         //Turns  on streaming of Voltage reading on A1
128
129      ClearTerminal ();
130      Serial.println(F("Request  to Output Voltage has been Received"));
131      OutputData = true;
132        
133      break;
134    
135      
136    case 'L':                         //Calls  routine to turn LED on or OFF depending on Rxint1 value
137
138      SetLED();
139      break;
140
141    case 'S':                        //Calls routine to display  all values in Receive command string
142
143      showParsedData();
144      break;
145   
146   case 'W':                         //Calls routine to set temp limit 0  to 70C and save in EEPROM
147
148      SetTemp();
149      break;   
150  }
151}
152  //********************************************************************************************************************************************************
153  // Serial print commands used to Clear Telnet Terminal Screen and position Cursor  to Home position
154
155  void ClearTerminal (void)
156  {
157    Serial.write(27);             // ESC command
158
159    Serial.print("[2J");          // Clear  Screen...actually fills screen with carriage returns so earlier terminal data is  not lost.
160    Serial.write(27);
161    Serial.print("[H");           // Cursor  to Home position
162  }
163
164
165
166//****************************************************************************************
167
168void  SetTemp(void)                    // Serial command W sets and stores the target  temperaturein EEPROM
169{
170  ClearTerminal ();                   //Clears Serial  Terminal Screen and positions Cursor at Home position
171
172  if (RxdInt1 == 0)  {
173    Serial.print(F(" Current Temp limit is "));
174    Serial.print(TempSet);
175    Serial.println(F("°C"));
176
177    Serial.println(F("Set the °C limit using  'W HW'  where HW= 1 to 70"));
178  }
179  else {
180    if (RxdInt1 > 0 && RxdInt1  < 71) {
181     TempSet = RxdInt1;
182     Serial.print(F(" Temperature limit has  been set to "));
183     Serial.print(TempSet);
184     Serial.println(F("°C"));
185    
186     EEPROM.write(2, TempSet);          //Save temperature threshold to  EEPROM address 2.
187      
188    }
189
190    Serial.print("Temperature Limit  = ");
191    Serial.print(TempSet);
192    Serial.println("°C");
193
194  }
195}
196
197//*************************
198void  SetLED (void)                    // Serial command sets and stores the target water  temperature
199{
200  ClearTerminal ();                   //Clears Serial Terminal  Screen and positions Cursor at Home position
201
202  if (RxdInt1 == 2) {
203    Serial.print(F("Turn  LED off"));
204    digitalWrite(LED, LOW);  //LED off
205    }
206  else if (RxdInt1==1){
207    Serial.print(F("Turn LED On"));
208    digitalWrite(LED, HIGH);  //LED On
209      }
210  else{
211    Serial.println(F("To Turn the LED ON send 'L 1'"));
212    Serial.println(F("To Turn LED off send 'L 2'"));
213     }
214}
215
216
217//*******************************************************************************************************************************************
218
219void  SerialRxWithEndMarker() {
220  //("expects to receive strin of characters terminated  in a LF. Max buffer size is currently 30 chars, text or Integer and an optional  floating point value seperated by a comma");
221  //("Enter data in this style  "C/I 24.7 CRLF  "   C/I maybe a text command String or Integer value, after the  space should be a float value );
222  // You can ommit the comma and Float value  if not required
223  //Note the parsing methods are now implemented in the functions  specific to commands
224
225  static byte ndx = 0;
226  char endMarker = '\n';
227  char rc;
228
229// if (Serial.available() > 0) {
230  while (Serial.available()  > 0 && NewData == false) {       //reads in new characters from serial buffer
231    rc = Serial.read();
232
233    if (rc != endMarker) {                                   //Looks  for a new line code to end the message
234      receivedChars[ndx] = rc;
235      ndx++;
236      if (ndx >= numChars) {
237        ndx = numChars - 1;
238      }
239    }
240    else {
241      receivedChars[ndx] = '\\0'; // terminate the string a new serial  message has been received
242      ndx = 0;
243      NewData = true;
244
245    }
246  }
247}
248
249
250//****************************************************************************************************
251void  parseData() {
252
253  // split the data into its parts
254  char * strtokIndx;  // this is used by strtok() as an index
255
256  strtokIndx = strtok(receivedChars,  " ");  // get the first part of string before the first space Char
257  strcpy(RxdSerialMessage,  strtokIndx);     // copy it to RxdSerial message - extracts text string at start  of a message if required
258
259  CommandChar = receivedChars[0];      //First Char  in the initial command string is used to identify the Command
260
261  strtokIndx  = strtok(NULL, " ");      // this continues where the previous call left off
262  RxdInt1 = atoi(strtokIndx);          // convert the next part of command upto  next space to an integer
263
264  strtokIndx = strtok(NULL, " ");
265  RxdInt2  = atoi(strtokIndx);          // convert this part to an Int - NOTE Currently Float  values are not used in any commands
266  //RxdFloat2 = atof(strtokIndx);        //  If you want to recieve Floats, - NOTE Currently Float values are not used in any  commands
267
268  strtokIndx = strtok(NULL, " ");
269  RxdInt3 = atoi(strtokIndx);          // convert this part to a float - NOTE Currently Float values are not  used in any commands
270
271  strtokIndx = strtok(NULL, " ");
272  RxdInt4 = atoi(strtokIndx);          // convert this part to a float - NOTE Currently Float values are not  used in any commands
273
274  strtokIndx = strtok(NULL, " ");
275  RxdInt5 = atoi(strtokIndx);          // convert this part to a float - NOTE Currently Float values are not  used in any commands
276
277  NewData = false;                      // The last  received message has been identified handled
278
279  OutputData = false;                 //  Stop Outputting Data values if a new message is received,
280
281}
282
283
284
285
286
287
288
289//*******************************************************************************************************************
290
291void  showParsedData() {
292   // Used for testing only to see how command and integer  values are extracted
293
294  Serial.print("Initial CommandChar ");
295  Serial.println(CommandChar);
296  Serial.print("RxdInt1 = ");
297  Serial.println(RxdInt1);
298  Serial.print("RxdInt2  = ");
299  Serial.println(RxdInt2);
300  Serial.print("RxdInt3 = ");
301  Serial.println(RxdInt3);
302  Serial.print("RxdInt4 = ");
303  Serial.println(RxdInt4);
304  Serial.print("RxdInt5  = ");
305  Serial.println(RxdInt5);
306
307}