   int roundedTemperature = round(temperature);
   int roundedDistance = round(distance);
 
+  char dataBuffer[TEMP_BUFFER_SIZE];
   snprintf(dataBuffer, TEMP_BUFFER_SIZE, "Test: %c %d %d",
     SENSOR_TYPE, roundedTemperature, roundedDistance);
 

  // -----------------------------
  rtc.begin();
  time_t unixTime = rtc.readDateTime();


  // 13. Combine time, distance, and temperature into a single string.

ARTF_RTC rtc(RTC_CS_PIN);
ARTF_SDCard sd(SD_CS_PIN);

void setup()
{
  pinMode(SD_CS_PIN, OUTPUT);
