prevent fine offset stations from saving data with zero interval

bin/weewx/drivers/fousb.py

@@ -220,7 +220,7 @@ import weewx.drivers
 import weewx.wxformulas
 
 DRIVER_NAME = 'FineOffsetUSB'
-DRIVER_VERSION = '1.9'
+DRIVER_VERSION = '1.10'
 
 def loader(config_dict, engine):
     return FineOffsetUSB(**config_dict[DRIVER_NAME])
@@ -1318,7 +1318,7 @@ class FineOffsetUSB(weewx.drivers.AbstractDevice):
                 while dts > dt and count < num_rec:
                     raw_data = self.get_raw_data(ptr)
                     data = self.decode(raw_data)
-                    if data['delay'] is None or data['delay'] > 30:
+                    if data['delay'] is None or data['delay'] < 1 or data['delay'] > 30:
                         logerr('invalid data in get_records at 0x%04x, %s' %
                                (ptr, dts.isoformat()))
                         dts -= datetime.timedelta(minutes=fixed_block['read_period'])

docs/changes.txt

@@ -63,6 +63,9 @@ Fixed bug in WS1 driver that caused crash if rain_total was None.
 If a file user/schemas.py still exists (a relic from V2.7 and earlier), it
 is renamed to user/schemas.py.old. Fixes issue #54.
 
+Fixed fine offset driver to warn about (and skip) historical data that have
+zero for interval.
+
 
 3.9.1 02/06/2019