Skip spurious bytes when testing for amb8465.

src/util.cc

@@ -1933,3 +1933,19 @@ bool isValidBps(string b)
     if (b == "115200") return true;
     return false;
 }
+
+size_t findBytes(vector<uchar> &v, uchar a, uchar b, uchar c)
+{
+    size_t p = 0;
+    while (p+2 < v.size())
+    {
+        if (v[p+0] == a &&
+            v[p+1] == b &&
+            v[p+2] == c)
+        {
+            return p;
+        }
+        p++;
+    }
+    return 0;
+}

src/util.h

@@ -214,4 +214,6 @@ std::string lookForExecutable(std::string prog, std::string bin_dir, std::string
 bool parseExtras(std::string s, std::map<std::string,std::string> *extras);
 void checkIfMultipleWmbusMetersRunning();
 
+size_t findBytes(std::vector<uchar> &v, uchar a, uchar b, uchar c);
+
 #endif

src/wmbus_amb8465.cc

@@ -592,6 +592,14 @@ AccessCheck detectAMB8465(Detected *detected, shared_ptr<SerialCommunicationMana
 
     // FF8A7A00780080710200000000FFFFFA00FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF003200021400FFFFFFFFFF010004000000FFFFFF01440000000000000000FFFF0B040100FFFFFFFFFF00030000FFFFFFFFFFFFFF0000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF17
 
+    size_t skip = findBytes(response, 0xff, 0x8A, 0x7A);
+    while (skip > 0)
+    {
+        // Sometimes there seems to be a leading 00 noise byte. Skip those.
+        response.erase(response.begin());
+        skip--;
+    }
+
     if (response.size() < 8 ||
         response[0] != 0xff ||
         response[1] != (0x80 | request[1]) ||