Script to log data and time accurately, may be a problem, but we do have the W, so maybe we can update wirelessly.

Scripts/Log-Date-and-Time.py

@@ -0,0 +1,34 @@
+import machine
+import utime
+
+sensor_temp = machine.ADC(machine.ADC.CORE_TEMP)
+conversion_factor = 3.3 / (65535)
+
+led_onboard = machine.Pin(25, machine.Pin.OUT)
+led_onboard.value(0)
+
+rtc=machine.RTC()
+
+file = open("temps.txt", "w")
+#file = open("temps.txt", "a") # To append to log file rather than overwrite
+
+while True:
+    reading = sensor_temp.read_u16() * conversion_factor
+    timestamp=rtc.datetime()
+    temperature = 27 - (reading - 0.706)/0.001721
+
+    timestring="%04d-%02d-%02d %02d:%02d:%02d"%(timestamp[0:3] +
+                                                timestamp[4:7])
+    file.write(timestring + "," + str(temperature) + "\n")
+    file.flush()
+    led_onboard.value(1)
+    utime.sleep(0.01)
+    led_onboard.value(0)
+
+    utime.sleep(30)
+
+# Notes
+# Given that space is at a premium when writing logs to files on the 
+# internal Flash, one option may be produce timestamps and then deltas or 
+# changes after that, forcing a full timestamp every so often to ensure 
+# things are synchronised