2021-07-15, 08:40 PM
(2021-07-15, 08:25 PM)Kever Wrote:(2021-07-09, 03:44 PM)Techstyle Wrote:(2021-07-08, 08:04 PM)Kever Wrote: I have taken the device I purchase, JBtek USB to RS485 Converter Adapter ch340T chip, and tested it on my laptop. It locks the cat /dev/ttyUSB0 output till unplugged. This is probably the problem.
I have ordered the following for it's replacement:https://www.amazon.ca/DTECH-RS485-RS422-Serial-Adapter/dp/B06WGQDV7Z
I have the Dtech one working on my system with a Garmin chartplotter and Raymarine Autopilot. I did have to connect - to + and vice versa though, but I think that will depend on the VHF
Was that specific to send nmea GPS to the VHF radio?
it seems like manufacturers are not specific about polarity on the NMEA0183 connection so try:
PI VHF
TX(+) --> RX(+)
TX(-) --> RX(-)
RX(+) --> TX(+)
RX(-) --> TX(-)
if that doesn't work, swap the polarity:
PI VHF
TX(+) --> RX(-)
TX(-) --> RX(+)
RX(+) --> TX(-)
RX(-) --> TX(+)
this worked for me on both a Raymarine autopilot and a Garmin Chartplotter.