2-25 
 
Definition of alarm light board J1 
Pin No.  Signal Name  Discription 
1)  
VPP 12V supply 
2)  
GND Ground 
3)  
SDA  Main control board IIC data signal 
4)  
SCL  Main control board IIC data signal 
5)  
VDD 3.3V supply 
 
2.1.5.4 Encoder Board 
User can rotate it to left or right, or press it down. 
 
 
Definition of encoder board J1 
Pin No.  Signal Name  Discription  Note 
1)  
VCC 5V supply  0.06A 
2)  
A Encoder output A 
High electrical level: [2.4, 5.25]V 
Low electrical level: [0, 0.4]V 
3)  
B Encoder output B 
High electrical level: [2.4, 5.25]V 
Low electrical level: [0, 0.4]V 
4)  
S2  Encoder is pressed down 
High electrical level: [2.4, 5.25]V 
Low electrical level: [0, 0.4]V 
5)  
GND Ground  /