ecc

src/pifmrds/control_pipe.c

@@ -152,6 +152,11 @@ ResultAndArg poll_control_pipe(int log) {
 				printf("Wrong PTY identifier! The PTY range is 0 - 31.\n");
 			}
 			resarg.res = CONTROL_PIPE_PTY_SET;
+		} else if(fifo[0] == 'E' && fifo[1] == 'C' && fifo[2] == 'C') {
+			arg[3] = 0;
+			set_rds_ecc((uint16_t) strtol(arg, NULL, 16));
+			if(log==1) printf("ECC set to: \"%s\"\n", arg);
+			resarg.res = CONTROL_PIPE_GENERIC_SET;
 		} else if(fifo[0] == 'P' && fifo[1] == 'W' && fifo[2] == 'R') {
 			int power_level = atoi(arg);
 			resarg.arg_int = power_level;

src/pifmrds/fm_mpx.c

@@ -48,10 +48,7 @@ float carrier_38[] = {0.0, 0.8660254037844386, 0.8660254037844388, 1.22464679914
 
 float carrier_19[] = {0.0, 0.5, 0.8660254037844386, 1.0, 0.8660254037844388, 0.5, 1.2246467991473532e-16, -0.5, -0.8660254037844384, -1.0, -0.8660254037844386, -0.5};
 
-float carrier_3125[] = {0.0, 0.7586133425663026, 0.9885355334735083, 0.5295297022607088, -0.29851481100169425, -0.918519035014914, -0.898390981891979, -0.2521582503964708}; // sine wave
-
 int phase_38 = 0;
-int phase_3125 = 0;
 int phase_19 = 0;
 
 float downsample_factor;
@@ -349,21 +346,14 @@ int fm_mpx_get_samples(float *mpx_buffer, fm_mpx_data *data) {
 
         // Generate the stereo mpx
         if(channels == 2 && !data->dstereo) {
-            if(1) {
+            // 4.5 and 0.9 are the volumes, thats because we dont have 75000 khz of deviation, instead we have 7500 khz, so that needs to be louder by 10 times than normal
-                // 4.5 and 0.9 are the volumes, thats because we dont have 75000 khz of deviation, instead we have 7500 khz, so that needs to be louder by 10 times than normal
+            mpx_buffer[i] +=  4.5*(out_left+out_right) + // Stereo sum signal
-                mpx_buffer[i] +=  4.5*(out_left+out_right) + // Stereo sum signal
+                4.5 * carrier_38[phase_38] * (out_left-out_right) + // Stereo difference signal
-                    4.5 * carrier_38[phase_38] * (out_left-out_right) + // Stereo difference signal
+            0.9*carrier_19[phase_19];                  // Stereo pilot tone
-                0.9*carrier_19[phase_19];                  // Stereo pilot tone
+            phase_19++;
-                phase_19++;
+            phase_38++;
-                phase_38++;
+            if(phase_19 >= 12) phase_19 = 0;
-                if(phase_19 >= 12) phase_19 = 0;
+            if(phase_38 >= 6) phase_38 = 0;
-                if(phase_38 >= 6) phase_38 = 0;
-            } else { // polar stereo (https://forums.stereotool.com/viewtopic.php?t=6233, https://personal.utdallas.edu/~dlm/3350%20comm%20sys/ITU%20std%20on%20FM%20--%20R-REC-BS.450-3-200111-I!!PDF-E.pdf)
-                mpx_buffer[i] +=  4.5*(out_left+out_right) + // Stereo sum signal (L+R)
-                    4.5 * carrier_3125[phase_3125] * (out_left-out_right); // Stereo difference signal
-                phase_3125++;
-                if(phase_3125 >= 8) phase_3125 = 0;
-            }
         } else if(channels == 1 || data->dstereo)
         {
             if(data->generate_multiplex) {

src/pifmrds/pi_fm_rds.cpp

@@ -43,30 +43,31 @@ typedef struct tx_data {
     uint32_t carrier_freq;
     char *audio_file;
     uint16_t pi;
+    uint16_t ecc;
     char *ps;
     char *rt;
     char *control_pipe;
-    int pty;
+    uint8_t pty;
     int af_array[100];
-    int raw;
+    uint8_t raw;
-    int drds;
+    uint8_t drds;
-    double preemp;
+    float preemp;
     int power;
     int rawSampleRate;
     int rawChannels;
     int deviation;
-    int ta;
+    uint8_t ta;
-    int tp;
+    uint8_t tp;
     float cutoff_freq;
     float audio_gain;
     float compressor_decay;
     float compressor_attack;
     float compressor_max_gain_recip;
-    int enablecompressor;
+    uint8_t enablecompressor;
-    int rds_ct_enabled;
+    uint8_t rds_ct_enabled;
     float rds_volume;
-    int disablestereo;
+    uint8_t disablestereo;
-    int log;
+    uint8_t log;
     float limiter_threshold;
 } tx_data;
 
@@ -111,6 +112,7 @@ int tx(tx_data *data) {
     // Initialize the RDS modulator
     char myps[9] = {0};
     set_rds_pi(data->pi);
+    set_rds_ecc(data->ecc);
     set_rds_ps(data->ps);
     set_rds_rt(data->rt);
     set_rds_pty(data->pty);
@@ -129,7 +131,7 @@ int tx(tx_data *data) {
         if(drds == 1) {
             printf("RDS Disabled (you can enable with control fifo with the RDS command)\n");
         } else {
-            printf("PI: %04X, PS: \"%s\".\n", data->pi, data->ps);
+            printf("PI: %04X, ECC: %02X, PS: \"%s\".\n", data->pi, data->ecc, data->ps);
             printf("RT: \"%s\"\n", data->rt);
 
             if(data->af_array[0]) {
@@ -226,6 +228,7 @@ int main(int argc, char **argv) {
         .carrier_freq = 100000000,
         .audio_file = NULL,
         .pi = 0x00ff,
+        .ecc = 0x0,
         .ps = "Pi-FmSa",
         .rt = "Broadcasting on a Raspberry Pi: Simply Advanced",
         .control_pipe = NULL,
@@ -275,6 +278,9 @@ int main(int argc, char **argv) {
         } else if(strcmp("-pi", arg)==0 && param != NULL) {
             i++;
             data.pi = atoi(param);
+        } else if(strcmp("-ecc", arg)==0 && param != NULL) {
+            i++;
+            data.ecc = atoi(param);
         } else if(strcmp("-ps", arg)==0 && param != NULL) {
             i++;
             data.ps = param;
@@ -393,7 +399,7 @@ int main(int argc, char **argv) {
         }
         else {
             fatal("Unrecognised argument: %s.\n"
-            "Syntax: pi_fm_rds [-freq freq] [-audio file] [-pi pi_code]\n"
+            "Syntax: pi_fm_rds [-freq freq] [-audio file] [-pi pi_code] [-ecc ecc_code]\n"
             "                  [-ps ps_text] [-rt rt_text] [-ctl control_pipe] [-pty program_type] [-raw play raw audio from stdin] [-disablerds] [-af alt freq] [-preemphasis us] [-rawchannels when using the raw option you can change this] [-rawsamplerate same business] [-deviation the deviation, default is 75000] [-tp] [-ta]\n", arg);
         }
     }

src/pifmrds/rds.c

@@ -30,6 +30,7 @@ float carrier_57[] = {0.0, 1.0, 1.2246467991473532e-16, -1.0}; // sine wave at 5
 
 struct {
     uint16_t pi;
+    uint16_t ecc;
     int ta;
     int pty;
     int tp;
@@ -145,16 +146,21 @@ void get_rds_group(int *buffer, int stereo, int ct_clock_enabled) { //ptyn?
             blocks[3] = rds_params.ps[ps_state*2] << 8 | rds_params.ps[ps_state*2+1];
             ps_state++;
             if(ps_state >= 4) ps_state = 0;
-        } else { // Type 2A groups
+        } else if(state < 8) { // Type 2A groups
             blocks[1] = 0x2000 | rds_params.tp << 10 | rds_params.pty << 5 | rds_params.ab << 4 | rt_state;
             blocks[2] = rds_params.rt[rt_state*4+0] << 8 | rds_params.rt[rt_state*4+1];
             blocks[3] = rds_params.rt[rt_state*4+2] << 8 | rds_params.rt[rt_state*4+3];
             rt_state++;
             if(rt_state >= 16) rt_state = 0;
+        } else {
+            blocks[1] = 0x1000 | rds_params.tp << 10 | rds_params.pty << 5;
+            blocks[2] = rds_params.ecc; // Things like LIC would require the first 1-3 bits set, but ecc has just 0s there
+            // block 3 unused
         }
     
         state++;
-        if(state >= 8) state = 0;
+        if(state >= 8 && rds_params.ecc == 0) state = 0;
+        if(state >= 9 && rds_params.ecc != 0) state = 0;
     }
     
     // Calculate the checkword for each block and emit the bits
@@ -287,3 +293,7 @@ void set_rds_ms(int ms) {
 void set_rds_ab(int ab) {
 	rds_params.ab = ab;
 }
+
+void set_rds_ecc(uint16_t ecc) {
+	rds_params.ecc = ecc;
+}

src/pifmrds/rds.h

@@ -49,6 +49,6 @@ extern void set_rds_af(int *af_array);
 extern void set_rds_tp(int tp);
 extern void set_rds_ms(int ms);
 extern void set_rds_ab(int ab);
-
+extern void set_rds_ecc(uint16_t ecc);
 
 #endif /* RDS_H */

src/pifmrds/rds_test.cpp

@@ -10,9 +10,10 @@ extern "C"
 int main() {
     set_rds_pi(0xff);
     set_rds_ps("TEST");
+    set_rds_ecc(0xFF);
     int af_array[] = {3, 2, 1, 0};
     set_rds_af(af_array);
-    for(int i = 0; i < 32; i++) {
+    for(int i = 0; i < 10; i++) {
         int buffer[BITS_PER_GROUP];
         get_rds_group(buffer, 0, 0);
         for(int j = 0; j < BITS_PER_GROUP; j++) {