Some RS485 shields are already available for the Raspberry Pi on the market, but these extensions are not suitable for professional use, because they come without a galvanic isolation between the RS485 bus and the Raspberry Pi. Without such isolation a damaging of the Raspberry Pi or malfunction of the device is possible, because of the large distances of a RS485 bus. Furthermore a full-duplex mode (RS422) is also not integrated.

Our shield comes with a lot of additional features:

• RS485 mode (half duplex)
• RS422 mode (full duplex)
• galvanic isolation between Raspberry Pi and connected RS485 bus
• enhanced ESD protection
• adjustable automatic transceiver switching for RS485 mode
• adjustable control of transceiver/receiver via GPIO pin
• adjustable Pull-Up, Pull-Down und terminating resistors
• indicator LEDs for RX and TX
• removable block terminal for bus connection
• many options adjustable via DIP switches

The RS485 is in use in many applications like industrial and home automation (for example MODBUS), lighting control (DMX), video surveillance (for example Pelco D) ...

If you like to know more about RS485 visit this website: http://www.radio-electronics.com/info/telecommunications_networks/rs485/rs-485-tutorial-basics.php

Datasheet and DIP Switch Settings

Datasheet RS485 shield Rev A.pdf

Adobe Acrobat Document 221.5 KB

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Schematic

RPI_RS485 Schematic V01-01-00.pdf

Adobe Acrobat Document 210.9 KB

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