Users Manual
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LSN50 LoRa Sensor Node User Manual 23 / 55
According to above diagram:
(
So
is the reading of ADC. So if ADC=0x05DC=0.9 v and VCC (BAT) is 2.9v
The
4.5K ohm
Since the Bouy is linear resistance from 10 ~ 70cm.
The position of Bouy is
, from the bottom of Bouy
2.4.5 Digital Interrupt
Digital Interrupt refers to pin PB14, and there are different trigger methods. When there is a
trigger, the LSN50 will send a packet to the server.
Example to use with door sensor
(Requires firmware > 1.5.1)
The door sensor is shown at right. It is a two wire
magnetic contact switch used for detecting the
open/close status of doors or windows.
When the two pieces are close to each other, the
2 wire output will be short or open (depending
on the type), while if the two pieces are away
from each other, the 2 wire output will be the
opposite status. So we can use LSN50 interrupt
interface to detect the status for the door or
window.
Below is the installation example:
Fix one piece of the magnetic sensor to the door and connect the two pins to LSN50 as
follows:
● One pin to LSN50’s PB14 pin
● The other pin to LSN50’s VCC pin
Install the other piece to the door. Find a place where the two pieces will be close to each
other when the door is closed. For this particular magnetic sensor, when the door is closed,
the output will be short, and PB14 will be at the VCC voltage.
Door sensors have two types: NC (Normal close) and NO (normal open). The
connection for both type sensors are the same. But the decoding for payload are
reverse, user need to modify this in the IoT Server decoder.
When door sensor is shorted, there will extra power consumption in the circuit, the
extra current is 3v3/R14 = 3v2/1Mohm = 0.3uA which can be ignored.