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@@ -1,3 +1,34 @@
+## 20240121
+
+Got TBeam working with GPS. Downlink from gateway is not working; had to authenticate using ABP.
+
+Need to visualize it in QGIS now. Create a view, grant view permission to previously-created role.
+
+First create a `tbeam` view:
+
+```sql
+CREATE OR REPLACE VIEW tbeam AS
+WITH data(id, dev_eui, time, alt, lat, lon, rssi) AS
+  (SELECT
+    deduplication_id,
+    dev_eui,
+    time,
+    CAST (object -> 'gpsLocation' -> '3' ->> 'altitude' AS FLOAT),
+    CAST (object -> 'gpsLocation' -> '3' ->> 'latitude' AS FLOAT),
+    CAST (object -> 'gpsLocation' -> '3' ->> 'longitude' AS FLOAT),
+    CAST (rx_info -> 0 ->> 'rssi' AS INTEGER)
+  FROM event_up)
+SELECT
+  id,
+  dev_eui,
+  time,
+  ST_SetSRID(ST_MakePoint(lon, lat, alt), 4326) AS location,
+  rssi
+FROM data
+WHERE dev_eui = 'fffe2002c855b594';
+GRANT SELECT ON tbeam TO qgis;
+```
+
 ## 20240117
 
 Example SQL query to create a `qgis_friendly` view that converts Cayenne GPS location into PostGIS point, includes unique ID, RSSI, time, and gatewayId, and filters on gatewayId: