diff --git a/src/energenie/drv/radio_test.c b/src/energenie/drv/radio_test.c
index 5952ff0..598a286 100644
--- a/src/energenie/drv/radio_test.c
+++ b/src/energenie/drv/radio_test.c
@@ -18,6 +18,33 @@
 
 #define REPEATS 8
 
+// preamble pulse with timing violation gap
+#define PREAMBLE 0x80, 0x00, 0x00, 0x00
+
+// Energenie 'random' 20 bit address is 0x6C6C6
+// 0110 1100 0110 1100 0110
+// 0 encoded as 8 (1000)
+// 1 encoded as E (1110)
+#define ADDR     0x8E, 0xE8, 0xEE, 0x88, 0x8E, 0xE8, 0xEE, 0x88, 0x8E, 0xE8
+
+// Energenie 'switch 1 ON' command  F 1111  (0xEE, 0xEE)
+#define SW1_ON  0xEE, 0xEE
+
+// Energenie 'switch 1 OFF' command E 1110  (0xEE, 0xE8)
+#define SW1_OFF 0xEE, 0xE8
+
+/* manual preamble, 20 bit encoded address, 4 encoded data bits */
+static uint8_t enc_1on[16]  = {PREAMBLE, ADDR, SW1_ON};
+static uint8_t enc_1off[16] = {PREAMBLE, ADDR, SW1_OFF};
+
+/* The 'radio' module knows nothing about the Energenie (HS1527) bit encoding,
+ * so this test code manually encodes the bits.
+ * For the full Python stack, there is an encoder module that can generate
+ * specific payloads. Repeats are done in radio_transmitter.
+ * The HRF preamble feature is no longer used, it's more predictable to
+ * put the preamble in the payload.
+ */
+
 
 /***** FORWARD FUNCTION PROTOTYPES *****/
 
@@ -44,42 +71,6 @@
     radio_init();
     radio_modulation(RADIO_MODULATION_OOK);
 
-    /* The 'radio' module knows nothing about the Energenie (HS1527) bit encoding,
-     * so this test code manually encodes the bits.
-     * For the full Python stack, there is an encoder module that can generate
-     * specific payloads. Repeats are done in radio_transmitter.
-     * The HRF preamble feature is no longer used, it's more predictable to
-     * put the preamble in the payload.
-     */
-
-    /* manual preamble, 20 bit encoded address, 4 encoded data bits */
-    static uint8_t enc_1on[16] = {
-        0x80, 0x00, 0x00, 0x00, // preamble pulse with timing violation gap
-        // Energenie 'random' 20 bit address is 0x6C6C6
-        // 0110 1100 0110 1100 0110
-        // 0 encoded as 8 (1000)
-        // 1 encoded as E (1110)
-        0x8E, 0xE8,  0xEE, 0x88,  0x8E, 0xE8,  0xEE, 0x88,  0x8E, 0xE8,
-        // Energenie 'switch 1 ON' command  F 1111  (0xEE, 0xEE)
-        0xEE, 0xEE
-        // Energenie 'switch 1 OFF' command E 1110  (0xEE, 0xE8)
-        //0xEE, 0xE8
-    };
-
-    static uint8_t enc_1off[16] = {
-        0x80, 0x00, 0x00, 0x00, // preamble pulse with timing violation gap
-        // Energenie 'random' 20 bit address is 0x6C6C6
-        // 0110 1100 0110 1100 0110
-        // 0 encoded as 8 (1000)
-        // 1 encoded as E (1110)
-        0x8E, 0xE8,  0xEE, 0x88,  0x8E, 0xE8,  0xEE, 0x88,  0x8E, 0xE8,
-        // Energenie 'switch 1 ON' command  F 1111  (0xEE, 0xEE)
-        //0xEE, 0xEE
-        // Energenie 'switch 1 OFF' command E 1110  (0xEE, 0xE8)
-        0xEE, 0xE8
-    };
-
-
     while (1)
     {
         /* Turn switch 1 on */