diff --git a/src/lmic_config.h b/src/lmic_config.h
index fb3a5816..dc55260a 100644
--- a/src/lmic_config.h
+++ b/src/lmic_config.h
@@ -21,7 +21,10 @@
 #define LMIC_USE_INTERRUPTS 1
 
 // time sync via LoRaWAN network, note: not supported by TTNv2
-// #define LMIC_ENABLE_DeviceTimeReq 1
+//#define LMIC_ENABLE_DeviceTimeReq 1
+
+// use callback event handlers, not onEvent() reference
+#define LMIC_ENABLE_onEvent 0
 
 // This tells LMIC to make the receive windows bigger, in case your clock is
 // faster or slower. This causes the transceiver to be earlier switched on,
diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 8b787580..ff8ecfe7 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -89,9 +89,7 @@ void lora_setupForNetwork(bool preJoin) {
     // other regions, this will need to be changed.
     LMIC_selectSubBand(1);
 #elif CFG_LMIC_EU_like
-    // setting for TheThingsNetwork
-    // TTN uses SF9, not SF12, for RX2 window
-    LMIC.dn2Dr = EU868_DR_SF9;
+    // settings for TheThingsNetwork
     // Enable link check validation
     LMIC_setLinkCheckMode(true);
 #endif
diff --git a/src/ota.cpp b/src/ota.cpp
index d78a6453..087b92e7 100644
--- a/src/ota.cpp
+++ b/src/ota.cpp
@@ -246,7 +246,7 @@ int do_ota_update() {
     goto retry;
   }
 
-#ifdef HAS_LED
+#if (HAS_LED != NOT_A_PIN)
 #ifndef LED_ACTIVE_LOW
   if (!Update.begin(contentLength, U_FLASH, HAS_LED, HIGH)) {
 #else
diff --git a/src/reset.cpp b/src/reset.cpp
index 0fa965d3..94f6626d 100644
--- a/src/reset.cpp
+++ b/src/reset.cpp
@@ -34,8 +34,15 @@ void do_after_reset(int reason) {
     RTC_runmode = RUNMODE_POWERCYCLE;
     break;
 
+  case SW_CPU_RESET: // 0x0c Software reset CPU
+                     // keep previous runmode (could be RUNMODE_UPDATE)
+    break;
+
   case DEEPSLEEP_RESET: // 0x05 Deep Sleep reset digital core
     RTC_runmode = RUNMODE_WAKEUP;
+#if (HAS_LORA)
+    // to be done: restore LoRaWAN channel configuration and datarate here
+#endif
     break;
 
   case SW_RESET:         // 0x03 Software reset digital core
@@ -46,11 +53,11 @@ void do_after_reset(int reason) {
   case RTCWDT_SYS_RESET: // 0x09 RTC Watch dog Reset digital core
   case INTRUSION_RESET:  // 0x0a Instrusion tested to reset CPU
   case TGWDT_CPU_RESET:  // 0x0b Time Group reset CPU
-  case SW_CPU_RESET:     // 0x0c Software reset CPU
   case RTCWDT_CPU_RESET: // 0x0d RTC Watch dog Reset CPU
   case EXT_CPU_RESET:    // 0x0e for APP CPU, reseted by PRO CPU
   case RTCWDT_RTC_RESET: // 0x10 RTC Watch dog reset digital core and rtc mode
   default:
+    RTC_runmode = RUNMODE_POWERCYCLE;
     break;
   }
 
@@ -66,6 +73,9 @@ void enter_deepsleep(const int wakeup_sec, const gpio_num_t wakeup_gpio) {
 #if (HAS_LORA)
   if (os_queryTimeCriticalJobs(ms2osticks(10000)))
     return;
+
+    // to be done: save LoRaWAN channel configuration here
+
 #endif
 
   // set up power domains