SubGhz: fix frequency determination in a frequency analyzer (#762)

applications/subghz/helpers/subghz_frequency_analyzer_worker.c

@@ -1,9 +1,28 @@
 #include "subghz_frequency_analyzer_worker.h"
+#include <lib/drivers/cc1101_regs.h>
 
 #include <furi.h>
 
 #include "../subghz_i.h"
 
+static const uint8_t subghz_preset_ook_58khz[][2] = {
+    {CC1101_FIFOTHR, 0x47}, // The only important bit is ADC_RETENTION, FIFO Tx=33 Rx=32
+    {CC1101_MDMCFG4, 0xF5}, // Rx BW filter is 58.035714kHz
+    {CC1101_TEST2, 0x81}, // FIFOTHR ADC_RETENTION=1 matched value
+    {CC1101_TEST1, 0x35}, // FIFOTHR ADC_RETENTION=1 matched value
+    /* End  */
+    {0, 0},
+};
+
+static const uint8_t subghz_preset_ook_650khz[][2] = {
+    {CC1101_FIFOTHR, 0x07}, // The only important bit is ADC_RETENTION
+    {CC1101_MDMCFG4, 0x17}, // Rx BW filter is 650.000kHz
+    {CC1101_TEST2, 0x88},
+    {CC1101_TEST1, 0x31},
+    /* End  */
+    {0, 0},
+};
+
 struct SubGhzFrequencyAnalyzerWorker {
     FuriThread* thread;
 
@@ -56,6 +75,8 @@ static int32_t subghz_frequency_analyzer_worker_thread(void* context) {
     while(instance->worker_running) {
         osDelay(10);
         frequency_rssi.rssi = -127.0f;
+        furi_hal_subghz_idle();
+        furi_hal_subghz_load_registers(subghz_preset_ook_650khz);
         for(size_t i = 0; i < subghz_frequencies_count; i++) {
             if(furi_hal_subghz_is_frequency_valid(subghz_frequencies[i])) {
                 furi_hal_subghz_idle();
@@ -74,6 +95,9 @@ static int32_t subghz_frequency_analyzer_worker_thread(void* context) {
             //  -0.5 ... 433.92 ... +0.5
             frequency_start = frequency_rssi.frequency - 250000;
             //step 10KHz
+            frequency_rssi.rssi = -127.0;
+            furi_hal_subghz_idle();
+            furi_hal_subghz_load_registers(subghz_preset_ook_58khz);
             for(uint32_t i = frequency_start; i < frequency_start + 500000; i += 10000) {
                 if(furi_hal_subghz_is_frequency_valid(i)) {
                     furi_hal_subghz_idle();