diff --git a/src/counter.c b/src/counter.c
index 88269a4..e82d34e 100644
--- a/src/counter.c
+++ b/src/counter.c
@@ -22,12 +22,11 @@ const int INTR_IN  = 19;
 const int SPI_CHAN = 0;
 const int SPI_SPEED = 1000000;
 
+const uint32_t PRECISION = 1000;
+const uint32_t COUNTER_FREQUENCY = 1e6;
+
 config_t cfg;
 
-const char EPSILON_KEY[] = "epsilon";
-const double DEFAULT_EPSILON = 0.01;
-
-uint32_t skipped = 0;
 
 
 void isr() {
@@ -81,22 +80,33 @@ int main (void) {
   struct timespec timestamp;
   uint32_t last_seconds = 0;
   uint32_t last_milliseconds = 0;
-
+  uint32_t mainsCntSum = 0;
+  uint32_t mainsCntCnt = 0;
 
   while (1) {
     uint32_t period = ringbufferGet();
+  
     clock_gettime(CLOCK_REALTIME, &timestamp);
     uint32_t current_seconds = timestamp.tv_sec;
     uint32_t current_milliseconds = timestamp.tv_nsec / 1e6;
-  
-    // add averaging and forming the struct here
     uint32_t duration = ((current_seconds - last_seconds) * 1000) + (current_milliseconds - last_milliseconds);
-    logmsg(LOG_DEBUG, "s: %lu, ns: %lu, d: %lu, p: %lu", current_seconds, current_milliseconds, duration, period);
+    // logmsg(LOG_DEBUG, "s: %lu, ns: %lu, d: %lu, p: %lu", current_seconds, current_milliseconds, duration, period);
+
+    mainsCntSum += period;
+    mainsCntCnt += 1;
 
     if (duration >= 1000) {
       logmsg(LOG_DEBUG, "one second is over");
       last_seconds = current_seconds;
       last_milliseconds = current_milliseconds;
+
+      uint32_t cnt = mainsCntSum / mainsCntCnt;
+      mainsCntSum = 0;
+      mainsCntCnt = 0;
+      uint32_t freq = PRECISION * COUNTER_FREQUENCY / cnt;
+
+      logmsg(LOG_DEBUG, "s: %lu, f: %lu", current_seconds, freq);
+
     }