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--- sdk:gps2serial [2015/05/15 13:30]
juraschek
+++ sdk:gps2serial [2020/03/25 12:08]
fachet [Script Summary]
@@ Line 5: / Line 5: @@
 ===== Script Summary  =====
-This Script connects to the GPS server via tcp. The NMEA Frames will be startet by the request "R" and will be then written to the serial interface.
+This Script connects to the GPS server and forwards the data to the first serial interface.
+GPS must be enabled and in RAW mode.
-The default serial parameter are 115200 8N1 (8 databit, no parity, 1 stop bit, no flow controll). This parameter can be configured at the begining of the script.
+The default serial parameters for GPS are 4800 8N1 (8 databit, no parity, 1 stop bit, no flow controll). This parameter can be configured at the begining of the script.
+Please use if possible a higher data rate e.g. 115200.
 ===== Pre Requierments =====
@@ Line 30: / Line 31: @@
 <code c>
-/* Serial Baud Rate 9600, 19200, 38400, 57600, 115200 */
+/* Serial Baud Rate 4800, 9600, 19200, 38400, 57600, 115200 */
-SER_SPEED=115200;
+SER_SPEED=4800;
 /*  number of data bits (5, 6, 7, 8) */
 SER_DATABIT=8;
@@ Line 68: / Line 69: @@
 <code c gps-to-serial.are>
-/* DESC: This script sends the local GPS NMEA stream (incl. serial/checksum) to a remote UDP server.
- * Copyright (C) 2013-2015 NetModule AG, Switzerland
- */
 /* Options to configure by user*/
-/* Serial Baud Rate 9600, 19200, 38400, 57600, 115200 */
+SER_SPEED = 4800;	/* Serial Baud Rate 4800, 9600, 19200, 38400, 57600, 115200 */
-SER_SPEED=115200;
+SER_DATABIT = 8;	/*  number of data bits (5, 6, 7, 8) */
-/*  number of data bits (5, 6, 7, 8) */
+SER_STOPBIT = 1;	/*  number of stop bits (1, 2) */
-SER_DATABIT=8;
+SER_PARITY = 0;		/* parity (0=no parity, 1=odd parity, 2=even parity) */
-/*  number of stop bits (1, 2) */
+SER_FLOW = 0;		/*  flow control (0=none, 1=xon/xoff, 2=hardware) */
-SER_STOPBIT=1;
+DEV = "SERIAL1";	/*  name of the Serial Interface */
-/* parity (0=no parity, 1=odd parity, 2=even parity) */
-SER_PARITY=0;
+/* GPS Deamon Parameters */
-/*  flow control (0=none, 1=xon/xoff, 2=hardware) */
+HOST = "127.0.0.1";	/* local host */
-SER_FLOW=0;
+PORT = (int) nb_config_get("gpsd.0.port");
-/*  name of the Serial Interface (Only changed if your device has more then one serial Interface (NB3710) */
-DEV = "SERIAL1";
+void usage() {
+    nb_syslog("Usage: gps2serial.are\n");
-void usage()
-{
-    nb_syslog("Usage: gps-udp-client.are <server> <port>");
     exit(1);
 }
 int start_serial() {
+    // printf("set serial attributes\n");
-    /* check serial port config */
+    if ((rc = nb_serial_setattr(DEV, SER_SPEED, SER_DATABIT, SER_STOPBIT, SER_PARITY, SER_FLOW)) != 0) {
-    status = nb_config_get("serial.0.status");
+        nb_syslog("ERROR: unable to set serial attributes (rc %d) to %s\n", rc, DEV);
-    if (status != "2") {
-        nb_syslog("Serial port is not enabled for us");
         return -1;
     }
+    // nb_syslog("Open serial device %s\n", DEV);
-    /* set attributes */
+    if ((fd = nb_serial_open(DEV)) < 0) {
-    rc = nb_serial_setattr(DEV, SER_SPEED, SER_DATABIT, SER_STOPBIT, SER_PARITY, SER_FLOW);
+        nb_syslog("ERROR: can't open serial port %s\n", DEV);
-    if (rc != 0) {
-        nb_syslog("ERROR: unable to set serial attributes (rc %d)", rc);
         return -1;
     }
-    /* open serial port */
-    fd = nb_serial_open(DEV);
-    if (fd < 0) {
-        return -1;
-    }
     return fd;
 }
-int connect_gpsd ()
+int connect_gpsd()
 {
-    for (attempt = 0; attempt < 60; attempt++) {
+    if (nb_config_get("gpsd.0.status") != "1" || nb_config_get("gpsd.0.cmode") != "1") {
-        sleep(1);
+    	nb_syslog("gpsd not enabled or not in RAW mode\n");
+        exit(2);
+    }
+    while (1) {
         sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-        if (sock < 0) {
+        if (sock < 0)
-            nb_syslog("Unable to create socket");
+            nb_syslog("Unable to create socket\n");
-            continue;
+        else if (connect(sock, HOST, PORT) < 0){
-        }
+            nb_syslog("Could not connect to GPS daemon\n");
-        nb_syslog("Connecting to GPS daemon");
-        if (connect(sock, "127.0.0.1", 2947) < 0){
-            nb_syslog("Could not connect to GPS daemon");
             close(sock);
-            continue;
+        } else {
+            nb_syslog("Successfully connected to GPS daemon\n");
+            return sock;
         }
-        nb_syslog("Requesting raw NMEA stream");
+      	sleep(10);
-        if (send(sock, "R\n") < 0) {
-            nb_syslog("Unable to request raw NMEA stream");
-            close(sock);
-            continue;
-        }
-        nb_syslog("Successfully connected to GPS daemon");
-        return sock;
     }
+    /* no return */
-    return -1;
 }
-SERVER = trim((string) argv[1]);
-PORT = (int) argv[2];
-SERIAL = struct_get(nb_status("system"), "SERIAL_NUMBER");
-if (SERIAL == "") {
-    nb_syslog("Unable to obtain serial number");
-    exit(1);
-}
 nb_syslog("starting serial");
-serial_fd = start_serial();
+if ((serial_fd = start_serial()) < 0 ) {
-if (serial_fd < 0 ) {
+    nb_syslog("Could not start serial, exiting\n");
-    nb_syslog("Could not start serial, exiting");
+    exit(3);
-    exit(1);
 }
+// printf("connect to gpsd\n");
 gpsd = connect_gpsd();
-if (gpsd < 0) {
-    nb_syslog("Could not start gpsd socket, exiting");
-    exit(1);
-}
-/* process NMEA stream */
-nb_syslog("Processing NMEA data");
+// printf("Processing NMEA data\n");
 while (1) {
-    /* wait for socket data  */
+    // printf("wait for data\n");
-    rv = select(gpsd, 3);
+    if ((rv = select(gpsd, 10)) == 0) {
-    if (rv > 0) {
+		// printf("Select timed out\n");
-        data = recv(gpsd);
+      	continue;
-        len = strlen(data);
+	}
-    } else if (rv < 0) {
+    if (rv < 0 || ( data = recv(gpsd)) == "") {
-        nb_syslog("select failed");
+        nb_syslog("Select or recv failed, re-connecting to GPS daemon\n");
-        len = -1;
+        if ((gpsd = connect_gpsd()) < 0)
-    } else {
+            exit(4);	/* can't connect */
-        /* nothing received */
         continue;
-    }
-    if (len <= 0) {
-        nb_syslog("Receive failed, re-connecting to GPS daemon");
-        close(gpsd);
-        gpsd = connect_gpsd();
-        if (gpsd < 0) {
-            exit(1);
-        }
-    } else {
-        str = strcat("PNMID,", SERIAL);
-        chars = explode(str);
-        checksum = 0;
-        for (i = 0; i < length(chars); i++) {
-            c = ord(chars[i]);
-            checksum ^= c;
-        }
-        sentence = sprintf("$%s*%02X\r\n", str, checksum);
-        data = strcat(data, sentence);
-        len = strlen(data);
-        nb_syslog("len: %i", len);
-        if (len > 0) {
-            sent = write(serial_fd, data, len);
-            if (sent != len) {
-                nb_syslog("Unable to send message via Serial, sent: %i, len: %i",sent, len);
-            }
-        }
     }
+    len = strlen(data);
+	// printf("write data to serial <%s> [%i]\n", data, len);
+    if (write(serial_fd, data, len) != len)
+       nb_syslog("Unable to send message via Serial, data %s, len: %i\n", data, len);
 }
 close(gpsd);
 close(serial_fd);
+exit(5);
-exit(0);
 </code>

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