Long, long ago: my project to send UDP (ESP8266) to PC running Processing:
GPS UDP Broadcaster - Everything ESP8266
/*
UDP listiner for Tardis Time Server by: M. Ray Burnette 20151008
Time Portal sends a UDP broadcast to all listeners on a random port (usually 4097)
Compiled under Linux Mint 17.3
Compiled under Arduino.cc IDE 1.6.8 on Linux Mint 17.3 on 20160206
ESP8266 core: http://arduino.esp8266.com/staging/package_esp8266com_index.json
Sketch uses 242,732 bytes (48%) of program storage space. Maximum is 434,160 bytes.
Global variables use 41,545 bytes (50%) of dynamic memory, leaving 40,775 bytes for local variables. Maximum is 81,920 bytes.
NOTE: After power-up with a "TardisTime" GPS over UDP transmitter functioning, allow 3 - 10 minutes to initialize
and Serial output is started.
*/
#define DEMO true
#define DIAG false
#include <Streaming.h> // \Documents\Arduino\libraries\Streaming (legacy) user-installed
#include <ESP8266WiFi.h>
#include <WiFiUdp.h>
#include <Wire.h>
// forward declarations seem to be necessary in 1.6.7+ under Linux
void StartUp_OLED();
void displayOn(void);
void displayOff(void);
static void clear_display(void);
static void SendChar(unsigned char data);
// static void sendCharXY(unsigned char data, int X, int Y);
static void sendcommand(unsigned char com);
static void setXY(unsigned char row,unsigned char col);
static void sendStr(unsigned char *string);
static void sendStrXY( char *string, int X, int Y);
static void init_OLED(void);
void Draw_WIFI();
void Draw_WAVES();
void Listener();
uint8_t hours, minutes, seconds; // hours, minure, seconds,
uint8_t day, month, year; // year, month, day;
unsigned int localPort = 8888; // any unused port on LAN
char packetBuffer[UDP_TX_PACKET_MAX_SIZE]; // buffer to hold incoming packet,
char ReplyBuffer[] = ""; // a null
IPAddress apIP(10, 10, 10, 1); // Private network address: local & gateway
IPAddress broadcastIP(255, 255, 255, 255); // https://en.wikipedia.org/wiki/Multicast
String Snumbers[] = {"00", "01", "02", "03", "04", "05", "06", "07", "08", "09", "10", "11",
"12", "13", "14", "14", "16", "17", "18", "19", "20", "21", "22", "23",
"24", "25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35",
"36", "37", "38", "39", "40", "41", "42", "43", "44", "45", "46", "47",
"48", "49", "50", "51", "52", "53", "54", "55", "56", "57", "58", "59"};
String Smonths[] = {"???", "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
WiFiUDP UDP; // UDP protocol on STA interface, localPort
void setup()
{
Serial.begin(115200); // Initialise Serial for older PMB-648
if(DIAG) {
Serial << (F("2015 Ray Burnette")) << endl;
Serial << (F("Tardis Time Listener Version 0.20151008")) << endl;
Serial << (F("Visit my project web page on http://www.hackster.io/rayburne")) << endl << endl;
}
WiFi.mode(WIFI_STA); // station mode
WiFi.disconnect();
WiFi.begin("TardisTime", ""); // The GPS server
// Wire.pins(int sda, int scl), etc
Wire.pins(0, 2); // on ESP-01.
Wire.begin();
StartUp_OLED(); // Init Oled and fire up!
Serial.println("OLED Init...");
clear_display(); // done here to simplify also setXY(0,0);
Draw_WAVES(); // Graphic is optional
sendStrXY(">>> Start-up <<<", 7, 0);
while (WiFi.status() != WL_CONNECTED) {
Serial.print(".");
delay(500);
}
clear_display();
sendStrXY(">WiFi Connected<", 0, 0);
while (! UDP.begin(localPort) ) // UDP protocol connected to localPort variable
{
delay(250);
}
sendStrXY("> UDP Started <", 0, 0);
char wifiIP = WiFi.localIP();
char *P = &wifiIP;
sendStrXY(P, 1, 0);
Serial.println("");
Serial.println("WiFi connected");
Serial.print("IP address: ");
Serial.println(WiFi.localIP());
Serial.print("Signal Strength: ");
Serial.println(WiFi.RSSI());
sendStrXY(">Listening: UDP<", 3, 0);
delay(10);
clear_display();
}
void loop()
{
yield(); // yield for RTOS
Listener(); // UPD (can you hear me now?)
}
void Listener() {
int packetSize = UDP.parsePacket(); // if there’s data available, read a packet
char cTD[8];
String Sdisplay;
Sdisplay.reserve(8);
if (packetSize)
{
IPAddress remote = UDP.remoteIP(); // Server provided UDP listening port
if (DIAG) { // For diags only
Serial << endl;
Serial << (F("Received packet of size: "));
Serial << (packetSize);
Serial << (F(" From remote: "));
for (int k = 0; k < 4; k++)
{
Serial << (remote[k], DEC);
if (k < 3)
{
Serial << (F("."));
}
}
Serial << (F(", port: "));
Serial << " UDPremotePort: " << (UDP.remotePort()) << endl;
}
UDP.read(packetBuffer, UDP_TX_PACKET_MAX_SIZE); // read the packet into packetBufffer
UDP.beginPacket(apIP, UDP.remotePort()); // send a reply, to the IP address and port that sent us the packet we received
UDP.write(ReplyBuffer); // should not be necessary but it seems that the ESP8266
UDP.endPacket(); // is stablized by the inclusion of the send
char *p = packetBuffer; // grab a pointer to buffer
p = strchr(p, ',') + 1; // position after 1st comma
yield();
uint32_t time = atoi(p);
hours = time / 10000;
minutes = (time % 10000) / 100;
seconds = (time % 100);
Serial << "Signal Strength: " << WiFi.RSSI() << endl;
Serial << (F("Time: ")) << ((hours<10)?"0":"") << hours << ":";
Serial << ((minutes<10)?"0":"") << minutes << ":";
Serial << ((seconds<10)?"0":"") << seconds << endl;
Sdisplay += Snumbers[hours] + ":" + Snumbers[minutes] + ":" + Snumbers[seconds];
Sdisplay.toCharArray(cTD, 9);
sendStrXY(" Tardis - Time", 0, 0);
sendStrXY("UTC Time/Date:", 2, 0);
sendStrXY(cTD, 4, 0);
yield();
// Parse to integer date field like Ladyada
p = strchr(p, ',') + 1; // A/V?
p = strchr(p, ',') + 1; // lat
p = strchr(p, ',') + 1; // N/S?
p = strchr(p, ',') + 1; // lon
p = strchr(p, ',') + 1; // E/W?
p = strchr(p, ',') + 1; // speed
p = strchr(p, ',') + 1; // angle
p = strchr(p, ',') + 1; // move pass for date DDMMYY
yield();
// nmea date field looks like: 090914 (European)
uint32_t fulldate = atoi(p);
day = (fulldate / 10000);
month = (fulldate % 10000) / 100;
year = (fulldate % 100);
Serial << "Date: " << ((month<10)?"0":"") << month << "/";
Serial << ((day<10)?"0":"") << day << "/" << "20";
Serial << ((year<10)?"0":"") << year << endl;
Sdisplay = "";
Sdisplay += Smonths[month] + Snumbers[day];
Sdisplay.toCharArray(cTD, 6);
sendStrXY(cTD, 4, 9);
yield();
} // if(packetSize)
} // Listener()
Complete OLED receiver code attached but very old.
TardisTimeReceive.zip (2.2 KB)