diff --git a/src/hwapi.cpp b/src/hwapi.cpp
index 26fc307..df154a6 100644
--- a/src/hwapi.cpp
+++ b/src/hwapi.cpp
@@ -2839,9 +2839,9 @@ void hwapi::bl_rebootDC(void) const
     sendWRcmd_setSendBlock160(len, buf);
 }
 
-void hwapi::bl_startBL(void) const
-{
+void hwapi::bl_startBL(void) const {
     uint8_t len, buf[20];
+    memset(buf, 0x00, sizeof(buf));
 
     len=dcBL_activatBootloader(buf);
     sendWRcmd_setSendBlock160(len, buf);
@@ -2861,9 +2861,10 @@ bool hwapi::bl_checkBL(void) const
 bool hwapi::bl_isUp(void) const
 {
     uint8_t receivedData[160];
-    uint8_t LL, nn;
+    uint8_t LL;
+
+    memset(receivedData, 0x00, sizeof(receivedData));
 
-    for (nn=0; nn<160; nn++) receivedData[nn]=0;
     LL=epi_getRawRecLength();
     if (LL>0)
     {