README.md: even nicer example

README.md

@@ -54,20 +54,19 @@ The library doesn't perform this conversion automatically for the following reas
 ```c
 char line[MINMEA_MAX_LENGTH];
 while (fgets(line, sizeof(line), stdin) != NULL) {
-    printf("%s", line);
     switch (minmea_sentence_id(line)) {
         case MINMEA_SENTENCE_RMC: {
             struct minmea_sentence_rmc frame;
             if (minmea_parse_rmc(&frame, line)) {
-                printf("$xxRMC: raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n",
+                printf("$RMC: raw coordinates and speed: (%d/%d,%d/%d) %d/%d\n",
                         frame.latitude.value, frame.latitude.scale,
                         frame.longitude.value, frame.longitude.scale,
                         frame.speed.value, frame.speed.scale);
-                printf("$xxRMC fixed-point coordinates and speed scaled to three decimal places: (%d,%d) %d\n",
+                printf("$RMC fixed-point coordinates and speed scaled to three decimal places: (%d,%d) %d\n",
                         minmea_rescale(&frame.latitude, 1000),
                         minmea_rescale(&frame.longitude, 1000),
                         minmea_rescale(&frame.speed, 1000));
-                printf("$xxRMC floating point degree coordinates and speed: (%f,%f) %f\n",
+                printf("$RMC floating point degree coordinates and speed: (%f,%f) %f\n",
                         minmea_tocoord(&frame.latitude),
                         minmea_tocoord(&frame.longitude),
                         minmea_tofloat(&frame.speed));
@@ -77,17 +76,17 @@ while (fgets(line, sizeof(line), stdin) != NULL) {
         case MINMEA_SENTENCE_GGA: {
             struct minmea_sentence_gga frame;
             if (minmea_parse_gga(&frame, line)) {
-                printf("$xxGGA: fix quality: %d\n", frame.fix_quality);
+                printf("$GGA: fix quality: %d\n", frame.fix_quality);
             }
         } break;
 
         case MINMEA_SENTENCE_GSV: {
             struct minmea_sentence_gsv frame;
             if (minmea_parse_gsv(&frame, line)) {
-                printf("$xxGSV: message %d of %d\n", frame.msg_nr, frame.total_msgs);
-                printf("$xxGSV: sattelites in view: %d\n", frame.total_sats);
+                printf("$GSV: message %d of %d\n", frame.msg_nr, frame.total_msgs);
+                printf("$GSV: sattelites in view: %d\n", frame.total_sats);
                 for (int i = 0; i < 4; i++)
-                    printf("$xxGSV: sat nr %d, elevation: %d, azimuth: %d, snr: %d dbm\n",
+                    printf("$GSV: sat nr %d, elevation: %d, azimuth: %d, snr: %d dbm\n",
                         frame.sats[i].nr,
                         frame.sats[i].elevation,
                         frame.sats[i].azimuth,