diff --git a/firmware/hackrf_usb/hackrf_usb.c b/firmware/hackrf_usb/hackrf_usb.c
index 4ceba12e..4eddcae9 100644
--- a/firmware/hackrf_usb/hackrf_usb.c
+++ b/firmware/hackrf_usb/hackrf_usb.c
@@ -186,25 +186,19 @@ void usb_configuration_changed(
 	}
 }
 
-int main(void) {
-	pin_setup();
-	enable_1v8_power();
-#ifdef HACKRF_ONE
-	enable_rf_power();
-#endif
-	cpu_clock_init();
-
-
-/* HACK!
-*/
+void usb_set_descriptor_by_serial_number(void)
+{
 	iap_cmd_res_t iap_cmd_res;
+	
 	/* Read IAP Serial Number Identification */
 	iap_cmd_res.cmd_param.command_code = IAP_CMD_READ_SERIAL_NO;
 	iap_cmd_call(&iap_cmd_res);
-	if(iap_cmd_res.status_res.status_ret == CMD_SUCCESS) {
+	
+	if (iap_cmd_res.status_res.status_ret == CMD_SUCCESS) {
 		usb_descriptor_string_serial_number[0] = 66;
 		usb_descriptor_string_serial_number[1] = USB_DESCRIPTOR_TYPE_STRING;
-		for(size_t i=0; i<32; i++) {
+		
+		for (size_t i=0; i<32; i++) {
 			const uint_fast8_t nibble = (iap_cmd_res.status_res.iap_result[i >> 3] >> (28 - (i & 7) * 4)) & 0xf;
 			const char c = (nibble > 9) ? ('a' + nibble - 10) : ('0' + nibble);
 			usb_descriptor_string_serial_number[2 + i * 2] = c;
@@ -214,6 +208,17 @@ int main(void) {
 		usb_descriptor_string_serial_number[0] = 2;
 		usb_descriptor_string_serial_number[1] = USB_DESCRIPTOR_TYPE_STRING;
 	}
+}
+
+int main(void) {
+	pin_setup();
+	enable_1v8_power();
+#ifdef HACKRF_ONE
+	enable_rf_power();
+#endif
+	cpu_clock_init();
+
+	usb_set_descriptor_by_serial_number();
 
 	usb_set_configuration_changed_cb(usb_configuration_changed);
 	usb_peripheral_reset();