feat(variants): Add support for TXCO on TLORA_V2_1_6 devices (#3124)

* feat(variants): Add support for TXCO on TLORA_V2_1_6 devices

* chore: remove long comment

* feat(variants): Add tlora-v2-1-1_6-tcxo to build matrix

* feat(variants): Use RADIOLIB_NC as DIO1 pin for tlora_v2_1_16 with TXCO

* Use generic naming scheme, add variant to build envs

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: code8buster <20384924+code8buster@users.noreply.github.com>

.github/workflows/main_matrix.yml

@@ -64,6 +64,7 @@ jobs:
           - board: tlora-v1
           - board: tlora_v1_3
           - board: tlora-v2-1-1_6
+          - board: tlora-v2-1-1_6-tcxo
           - board: tlora-v2-1-1_8
           - board: tbeam
           - board: heltec-ht62-esp32c3-sx1262

platformio.ini

@@ -15,6 +15,7 @@ default_envs = tbeam
 ;default_envs = tlora_v1_3
 ;default_envs = tlora-v2
 ;default_envs = tlora-v2-1-1_6
+;default_envs = tlora-v2-1-1_6-tcxo
 ;default_envs = tlora-t3s3-v1
 ;default_envs = lora-relay-v1 # nrf board
 ;default_envs = t-echo

src/main.cpp

@@ -248,6 +248,11 @@ void setup()
     digitalWrite(PIN_EINK_PWR_ON, HIGH);
 #endif
 
+#if defined(LORA_TCXO_GPIO)
+    pinMode(LORA_TCXO_GPIO, OUTPUT);
+    digitalWrite(LORA_TCXO_GPIO, HIGH);
+#endif
+
 #ifdef ST7735_BL_V03 // Heltec Wireless Tracker PCB Change Detect/Hack
 
     rtc_clk_32k_enable(true);

variants/tlora_v2_1_16/variant.h

@@ -16,5 +16,13 @@
 #define USE_RF95
 #define LORA_DIO0 26 // a No connect on the SX1262 module
 #define LORA_RESET 23
+
+// In the T3 V1.6.1 TXCO version, GPIO 33 is connected to Radio’s
+// internal temperature-compensated crystal oscillator enable
+#ifdef LORA_TCXO_GPIO
+#define LORA_DIO1 RADIOLIB_NC // no-connect on sx127x module
+#else
 #define LORA_DIO1 33 // https://www.thethingsnetwork.org/forum/t/big-esp32-sx127x-topic-part-3/18436
+#endif
+
 #define LORA_DIO2 32 // Not really used

variants/tlora_v2_1_16_tcxo/platformio.ini

@@ -0,0 +1,9 @@
+[env:tlora-v2-1-1_6-tcxo]
+extends = esp32_base
+board = ttgo-lora32-v21
+build_flags = 
+  ${esp32_base.build_flags}
+  -D TLORA_V2_1_16
+  -I variants/tlora_v2_1_16
+  -D GPS_POWER_TOGGLE ; comment this line to disable triple press function on the user button to turn off gps entirely.
+  -D LORA_TCXO_GPIO=33