RS485 interface Pi Zero

RS485 adapter for the pi zero

This project is an auto direction sensing non isolated RS485 transceiver board in the raspberry pi zero shield form factor. It also has 2 LED’s for indicating transmitted and received data

Schematic of the RS485 Adapter

The board is a 2 layer PCB and can be used with all the newer models of the raspberry pi as shown below 

RS485 adapter layout

 
The bill of materials for the project is below

QTY  PART-REFS           VALUE

—       ———                     —–

Resistors

———

1       R1                            100

2       R2,R4                      560

1       R3                           3.9K

1       R5                           120

2       R6,R7                     10K

2       R8,R9                      270

 

Capacitors

———-

2       C3,C6                     10n

1       C8                           100n

 

Integrated Circuits

——————-

1       U1                          SP3483E

1       U2                          555

1       U4                          SN74LVC2G17

 

Diodes

——

1      D1                         1N4148

2      D2,D3                    LED

 

Miscellaneous

————-

1      J1                           TBLOCK-I3

1      J2                          CONN-DIL40

6       J3,J4,J7-J10          CONN-H2