additional whiskers

src/codecs/cats/whisker.c

@@ -3,6 +3,48 @@
 
 #include "whisker.h"
 
+#ifdef RS41
+#define HARDWARE_ID 0x7d00
+#endif
+#ifdef DFM17
+#define HARDWARE_ID 0x7d01
+#endif
+
+#define SOFTWARE_ID 0x00
+
+static inline void cats_push_f16(cats_packet *p, float val)
+{
+    union {
+        float f;
+        uint32_t u;
+    } fu = { .f = val };
+
+    assert(sizeof fu.f == sizeof fu.u);
+
+    uint32_t f32 = fu.u;
+    uint32_t sign = (f32 >> 16) & 0x8000;
+    uint32_t exponent = ((f32 >> 23) - 127 + 15) & 0x1F;
+    uint32_t mantissa = f32 & 0x007FFFFF;
+    uint32_t f16 = sign | (exponent << 10) | (mantissa >> 13);
+
+    p->data[p->len++] = f16;
+    p->data[p->len++] = f16 >> 8;
+}
+
+static inline void cats_push_u16(cats_packet *p, uint16_t val)
+{
+    for(int i = 0; i < 2; i++) {
+        p->data[p->len++] = val >> (i * 8);
+    }
+}
+
+static inline void cats_push_i32(cats_packet *p, int32_t val)
+{
+    for(int i = 0; i < 4; i++) {
+        p->data[p->len++] = val >> (i * 8);
+    }
+}
+
 void cats_append_identification_whisker(cats_packet *packet, char *callsign, uint8_t ssid, uint16_t icon)
 {
     packet->data[packet->len++] = 0x00; // type = identidication
@@ -15,6 +57,18 @@ void cats_append_identification_whisker(cats_packet *packet, char *callsign, uin
     packet->data[packet->len++] = ssid; // ssid
 }
 
+void cats_append_gps_whisker(cats_packet *packet, gps_data gps)
+{
+    packet->data[packet->len++] = 0x02; // type = gps
+    packet->data[packet->len++] = 14; // len
+    cats_push_i32(packet, gps.latitude_degrees_1000000 / 90 * ((1<<31) / 1000000)); // lat
+    cats_push_i32(packet, gps.longitude_degrees_1000000 / 180 * ((1<<31) / 1000000)); // lon
+    cats_push_f16(packet, gps.altitude_mm / 100.0); // alt
+    packet->data[packet->len++] = 0; // max error = 0m
+    packet->data[packet->len++] = gps.heading_degrees_100000 * 128 / 180 / 100000; // heading
+    cats_push_f16(packet, gps.ground_speed_cm_per_second / 100.0); // horizontal speed
+}
+
 void cats_append_comment_whisker(cats_packet *packet, char *comment)
 {
     packet->data[packet->len++] = 0x03; // type = comment
@@ -24,3 +78,23 @@ void cats_append_comment_whisker(cats_packet *packet, char *comment)
     memcpy(packet->data + packet->len, comment, comment_len);
     packet->len += comment_len;
 }
+
+void cats_append_node_info_whisker(cats_packet *packet, telemetry_data *data)
+{
+    uint8_t *d = packet->data;
+    size_t *l = &packet->len;
+
+    d[(*l)++] = 0x09; // type = node info
+    d[(*l)++] = 10; // len
+    // bitmask
+    d[(*l)++] = 0;
+    d[(*l)++] = 0;
+    d[(*l)++] = 0b11110011;
+
+    cats_push_u16(packet, HARDWARE_ID);
+    d[(*l)++] = SOFTWARE_ID;
+    d[(*l)++] = 21; // vertical antenna -> ~5.25 dBi gain
+    d[(*l)++] = CATS_REPORTED_TX_POWER_DBM * 4.0; // TX power
+    d[(*l)++] = data->battery_voltage_millivolts / 100; // voltage
+    d[(*l)++] = data->internal_temperature_celsius_100 / 100; // transmitter temperature
+}

src/codecs/cats/whisker.h

@@ -4,8 +4,12 @@
 #include <stdint.h>
 
 #include "cats.h"
+#include "../../gps.h"
+#include "../../telemetry.h"
 
 void cats_append_identification_whisker(cats_packet *packet, char *callsign, uint8_t ssid, uint16_t icon);
+void cats_append_gps_whisker(cats_packet *packet, gps_data gps);
 void cats_append_comment_whisker(cats_packet *packet, char *message);
+void cats_append_node_info_whisker(cats_packet *packet, telemetry_data *data);
 
 #endif

src/config.h

@@ -345,6 +345,7 @@
 #define CATS_SSID 24
 #define CATS_ICON 8237
 #define CATS_COMMENT "I am a radiosonde. Hear me meow!"
+#define CATS_REPORTED_TX_POWER_DBM 20
 
 // Schedule transmission every N seconds, counting from beginning of an hour (based on GPS time). Set to zero to disable time sync.
 // See the README file for more detailed documentation about time sync and its offset setting

src/radio_payload_cats.c

@@ -31,6 +31,15 @@ uint16_t radio_cats_encode(uint8_t *payload, uint16_t length, telemetry_data *te
     cats_packet packet = cats_create(data);
     cats_append_identification_whisker(&packet, CATS_CALLSIGN, CATS_SSID, CATS_ICON);
     cats_append_comment_whisker(&packet, message);
+
+    if(GPS_HAS_FIX(telemetry_data->gps) &&
+       (telemetry_data->gps.latitude_degrees_1000000 != 0 ||
+        telemetry_data->gps.longitude_degrees_1000000 != 0)) {
+        cats_append_gps_whisker(&packet, telemetry_data->gps);
+    }
+
+    cats_append_node_info_whisker(&packet, telemetry_data);
+
     int len = cats_fully_encode(packet, cur);
     free(data);