diff --git a/include/esp32-lora.h b/include/esp32-lora.h
index f29d1f4..876bf50 100644
--- a/include/esp32-lora.h
+++ b/include/esp32-lora.h
@@ -98,7 +98,7 @@
 
 #define ERR_LOR_VERSION_MISMATCH (01)
 
-#define LORA32_DEFAULT_CONFIG() {\
+#define LORA32_DEFAULT_CONFIG() (lora32_cfg_t){\
   .bandwidth = 7,\
   .codingRate = 5,\
   .frequency = 915000000,\
@@ -134,6 +134,7 @@ typedef void (*cadDetectedCallback)(lora32_cfg_t *lora);
 
 typedef struct {
   EventGroupHandle_t state;
+  void *driver;
 } lora32_handle_t;
 
 typedef struct lora32_modem_status_t {
diff --git a/main/esp32-lora.c b/main/esp32-lora.c
index ef0ca66..048d025 100644
--- a/main/esp32-lora.c
+++ b/main/esp32-lora.c
@@ -43,7 +43,7 @@ uint8_t lora32_read_reg(lora32_cfg_t *lora, uint8_t address) {
 
 	ESP_ERROR_CHECK(spi_device_transmit(lora->spi, &t));
 
-  ESP_LOGV(TAG, "<%2X<%2X", address, t.rx_data[1]);
+  ESP_LOGV(TAG, "<%02X<%02X", address, t.rx_data[1]);
 
   xSemaphoreGive(spi_semaphore);
 
@@ -150,9 +150,17 @@ void lora32_enable_tx(lora32_cfg_t *lora) {
 }
 
 void lora32_send(lora32_cfg_t *lora, uint8_t *data, uint8_t len) {
-  if(lora == NULL) return;
+  if(lora == NULL) {
+    ESP_LOGE(TAG, "lora NULL");
 
-  xEventGroupWaitBits(lora->handle.state, MODE_ALL ^ MODE_TX, true, false, portMAX_DELAY);
+    return;
+  } else {
+    ESP_LOGD(TAG, "lora: %p", lora);
+  }
+
+  if((xEventGroupGetBits(lora->handle.state) & MODE_TX) == MODE_TX) {
+    xEventGroupWaitBits(lora->handle.state, MODE_ALL ^ MODE_TX, true, false, portMAX_DELAY);
+  }
 
   ESP_ERROR_CHECK(spi_device_acquire_bus(lora->spi, portMAX_DELAY));