For maximum connectivity, netPI/Edge Gateway “Connect” devices have a slot at their bottom for the insertion of various extension modules named NPIX (NetPIeXpansion). A containerized Node-RED software example under https://hub.docker.com/r/hilschernetpi/netpi-nodered enables their immediate use when installed. The source code is open, linked, and serves as a programming reference for other programming scenarios/languages. The NPIX board/slot dimensions and connector assignment are publicly accessible to the public and allow developers to create their own NPIX-designs. For more information, follow the link: https://www.netiot.com/netpi/industrial-raspberry-pi-3.
RS232 serial interface module for netPI/netFIELD Connect
Freely programmable serial RS-232 interface
Internally connects to Raspberry Pi "Mini UART" on /dev/ttyS0
1 start/stop bit, 7/8 data bits, no parity bit
Example of Node-RED on DockerHub/GitHub