Allow to specify preamble length and select modem type from platformio ini

Author: sh123

include/config.h

@@ -2,7 +2,7 @@
 #define CONFIG_H
 
 // Uncomment for SX126X module usage
-#define USE_SX126X
+// #define USE_SX126X
 
 // Check your module name at https://github.com/jgromes/RadioLib/wiki/Modules
 #ifdef USE_SX126X
@@ -69,6 +69,7 @@
 #define CFG_LORA_EXPLICIT     true        // header mode, true - explicit, false - implicit
 #define CFG_LORA_SYNC         0x12        // sync word (0x12 - private used by other trackers, 0x34 - public used by LoRaWAN)
 #define CFG_LORA_PWR          20          // output power in dBm
+#define CFG_LORA_PREAMBLE     8           // preamble length from 6 to 65535
 
 // WiFi client and AP options
 #define CFG_WIFI_ENABLE_AP    false       // run as wifi access point (for CFG_KISS_TCP_IP mode)

include/loraprs_config.h

@@ -21,6 +21,7 @@ struct Config
   int LoraSync;         // lora sync word/packet id, 0x34
   int LoraCrc;          // lora crc mode, 0 - disabled, 1 - 1 byte, 2 - 2 bytes
   bool LoraExplicit;    // lora header mode, true - explicit, false - implicit
+  int LoraPreamble;     // lora preamble length from 6 to 65535
 
   // lora hardware pinouts and isr
   byte LoraPinSs;       // lora ss pin

platformio.ini

@@ -1,6 +1,6 @@
 [platformio]
 description = ESP32 LoRA APRS modem
-default_envs = esp32dev
+default_envs = esp32dev_sx126x_modem
 
 [env]
 platform = espressif32 @ 5.2.0
@@ -19,18 +19,31 @@ check_flags =
   cppcheck: --suppress=*:*.pio\* --inline-suppr -DCPPCHECK
 check_skip_packages = yes
 
-[env:esp32dev]
+[env:esp32dev_sx126x_modem]
 board = esp32dev
 build_flags =
-  '-D CFG_IS_CLIENT_MODE=true'
+  -D CFG_IS_CLIENT_MODE=true
+  -D USE_SX126X
 
-[env:esp32dev_igate]
+[env:esp32dev_sx126x_igate]
 board = esp32dev
 board_build.f_cpu = 240000000L
 build_flags =
-  '-D CFG_IS_CLIENT_MODE=false'
+  -D CFG_IS_CLIENT_MODE=false
+  -D USE_SX126X
 
-[env:ttgo-lora32-v1]
+[env:esp32dev_sx127x_modem]
+board = esp32dev
+build_flags =
+  -D CFG_IS_CLIENT_MODE=true
+
+[env:esp32dev_sx127x_igate]
+board = esp32dev
+board_build.f_cpu = 240000000L
+build_flags =
+  -D CFG_IS_CLIENT_MODE=false
+
+[env:ttgo-lora32-v1_modem]
 board = ttgo-lora32-v1
 build_flags =
-  '-D CFG_IS_CLIENT_MODE=true'
+  -D CFG_IS_CLIENT_MODE=true

src/loraprs_service.cpp

@@ -239,6 +239,7 @@ void Service::setupRig(long loraFreq, long bw, int sf, int cr, int pwr, int sync
     LOG_ERROR("Radio start error:", state);
   }
   rig_->setCRC(crcBytes);
+  rig_->setPreambleLength(config_.LoraPreamble);
 #ifdef USE_SX126X
     #pragma message("Using SX126X")
     LOG_INFO("Using SX126X module");

src/main.cpp

@@ -41,6 +41,7 @@ void initializeConfig(LoraPrs::Config &cfg) {
   cfg.LoraCrc = CFG_LORA_CRC; // set to 0 to disable
   cfg.LoraExplicit = CFG_LORA_EXPLICIT;
   cfg.LoraPower = CFG_LORA_PWR;
+  cfg.LoraPreamble = CFG_LORA_PREAMBLE;
 
   // lora pinouts
   cfg.LoraPinSs = CFG_LORA_PIN_SS;