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 * Schematic
   + ![](./Pirschematic.png)
+  + ![](./pir-pcb-800x564.jpg)
+* [Reference](https://www.tweaking4all.com/hardware/pir-sensor/)
+  + Initial Warm Up : 30 to 60 seconds to stabilize
+  + Delay Time : (2s - 200s) Determines how long the PIR will keep the Output “High” (ON) after detecting motion.
+  + Sensitivity : Set the sensing “range”. 3 - 6 meter
+  + Retrigger Jumper
+    - L : non-retriggering. Output ON and OFF upon detection
+    - H (Default) : retriggering. Output remains ON upon detection
+
 * [Datasheet](./BISS0001-SilvanChip.pdf)
 * [ESP8266](./esp8266.md)
   + GPIO12 : PIR Out
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