Added support for the LR1121 radio to the NRF52 Pro-Micro (#5515)

* Added support for the LR1121 radio

Added support for the LR1121 radio, tested as functional with an E80-900M2213S from CDEbyte.

* Swap PNG for PDF

* remove PNG

* put TCXO voltage to 1.8, as in example file

It worked at 1.6v, but ¯\_(ツ)_/¯

* Hopefully this will appease Trunk

* Update rf switch pins and Schematic

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

variants/diy/nrf52_promicro_diy_tcxo/rfswitch.h

@@ -0,0 +1,17 @@
+#include "RadioLib.h"
+
+// RF Switch Matrix SubG RFO_HP_LF / RFO_LP_LF / RFI_[NP]_LF0
+// DIO5 -> RFSW0_V1
+// DIO6 -> RFSW1_V2
+// DIO7 -> ANT_CTRL_ON + ESP_IO9/LR_GPS_ANT_DC_EN -> RFI_GPS (Bias-T GPS) (LR11x0 only)
+
+static const uint32_t rfswitch_dio_pins[] = {RADIOLIB_LR11X0_DIO5, RADIOLIB_LR11X0_DIO6, RADIOLIB_LR11X0_DIO7, RADIOLIB_NC,
+                                             RADIOLIB_NC};
+
+static const Module::RfSwitchMode_t rfswitch_table[] = {
+    // mode                  DIO5  DIO6  DIO7
+    {LR11x0::MODE_STBY, {LOW, LOW, LOW}},  {LR11x0::MODE_RX, {HIGH, LOW, LOW}},
+    {LR11x0::MODE_TX, {LOW, HIGH, LOW}},   {LR11x0::MODE_TX_HP, {LOW, HIGH, LOW}},
+    {LR11x0::MODE_TX_HF, {LOW, LOW, LOW}}, {LR11x0::MODE_GNSS, {LOW, LOW, HIGH}},
+    {LR11x0::MODE_WIFI, {LOW, LOW, LOW}},  END_OF_MODE_TABLE,
+};

variants/diy/nrf52_promicro_diy_tcxo/variant.h

@@ -122,12 +122,13 @@ NRF52 PRO MICRO PIN ASSIGNMENT
 #define USE_SX1262
 #define USE_RF95
 #define USE_SX1268
+#define USE_LR1121
 
 // RF95 CONFIG
 
-#define LORA_DIO0 (0 + 29) // P0.10 IRQ
+#define LORA_DIO0 (0 + 29) // P0.29 BUSY
 #define LORA_DIO1 (0 + 10) // P0.10 IRQ
-#define LORA_RESET (0 + 9) // P0.09
+#define LORA_RESET (0 + 9) // P0.09 NRST
 
 // RX/TX for RFM95/SX127x
 #define RF95_RXEN (0 + 17)    // P0.17
@@ -143,6 +144,19 @@ NRF52 PRO MICRO PIN ASSIGNMENT
 #define SX126X_RXEN (0 + 17)     // P0.17
 #define SX126X_TXEN RADIOLIB_NC  // Assuming that DIO2 is connected to TXEN pin. If not, TXEN must be connected.
 
+// LR1121
+#ifdef USE_LR1121
+#define LR1121_IRQ_PIN (0 + 10)      // P0.10 IRQ
+#define LR1121_NRESET_PIN LORA_RESET // P0.09 NRST
+#define LR1121_BUSY_PIN (0 + 29)     // P0.29 BUSY
+#define LR1121_SPI_NSS_PIN LORA_CS   // P1.13
+#define LR1121_SPI_SCK_PIN LORA_SCK
+#define LR1121_SPI_MOSI_PIN LORA_MOSI
+#define LR1121_SPI_MISO_PIN LORA_MISO
+#define LR11X0_DIO3_TCXO_VOLTAGE 1.8
+#define LR11X0_DIO_AS_RF_SWITCH
+#endif
+
 // #define SX126X_MAX_POWER 8 set this if using a high-power board!
 
 /*
@@ -164,6 +178,7 @@ settings.
 | Seeed        | Wio-SX1262       | yes  | Int       | Sooooo cute!                          |
 | AI-Thinker   | RA-02            | No   | Int       | SX1278 **433mhz band only**           |
 | RF Solutions | RFM95            | No   | Int       | Untested                              |
+| Ebyte        | E80-900M2213S    | Yes  | Int       | LR1121 radio                          |
 
 */
 
@@ -179,4 +194,4 @@ extern float tcxoVoltage; // make this available everywhere
  *        Arduino objects - C++ only
  *----------------------------------------------------------------------------*/
 
-#endif
+#endif