diff --git a/librfm95.c b/librfm95.c
index 062d89f..8f68ff7 100644
--- a/librfm95.c
+++ b/librfm95.c
@@ -74,7 +74,7 @@
     }
 }
 
-static bool initFSK(uint8_t node) {
+static bool initFSK(uint8_t node, uint8_t cast) {
     // bit rate 9.6 kBit/s
     // regWrite(BITRATE_MSB, 0x0d);
     // regWrite(BITRATE_LSB, 0x05);
@@ -138,7 +138,7 @@
 
     // node and broadcast address
     regWrite(RFM_FSK_NODE_ADDR, node);
-    regWrite(RFM_FSK_CAST_ADDR, RFM_CAST_ADDRESS);
+    regWrite(RFM_FSK_CAST_ADDR, cast);
 
     // set TX start condition to "at least one byte in FIFO"
     regWrite(RFM_FSK_FIFO_THRESH, 0x8f);
@@ -191,7 +191,7 @@
     return true;
 }
 
-bool rfmInit(uint64_t freq, uint8_t node, bool _lora) {
+bool rfmInit(uint64_t freq, uint8_t node, uint8_t cast, bool _lora) {
     lora = _lora;
 
     // wait a bit after power on
@@ -234,7 +234,7 @@
         // FSK mode, FSK modulation, high frequency mode, sleep mode
         regWrite(RFM_OP_MODE, 0x00);
 
-        return initFSK(node);
+        return initFSK(node, cast);
     }
 }
 
diff --git a/librfm95.h b/librfm95.h
index 07708ba..4032bf1 100644
--- a/librfm95.h
+++ b/librfm95.h
@@ -108,7 +108,6 @@
 #define RFM_MASK_MODE           0x07
 
 #define RFM_F_STEP              61035
-#define RFM_CAST_ADDRESS        0x84
 
 #define RFM_DBM_MIN             2
 #define RFM_DBM_MAX             17
@@ -168,12 +167,16 @@
 
 /**
  * Initializes the radio module in FSK or LoRa mode with the given carrier 
- * frequency in kilohertz and node address. Returns true on success, 
- * false otherwise.
+ * frequency in kilohertz and node and brodcast address. 
+ * Returns true on success, false otherwise.
  * 
+ * @param freq carrier frequency
+ * @param node address
+ * @param broadcast address
+ * @param lora LoRa or FSK mode
  * @return success
  */
-bool rfmInit(uint64_t freq, uint8_t node, bool lora);
+bool rfmInit(uint64_t freq, uint8_t node, uint8_t cast, bool lora);
 
 /**
  * Reads interrupt flags. Should be called when any interrupt occurs