2019-06-01, 06:50 PM
Ok. Just to confirm, the half-duplex dongle, (CH340T chip) RS422/RS425 usb A to mini-wire clamp posts worked just fine.
(From Amazon, ~$7, https://www.amazon.com/JBtek-Converter-A...27KYJ19G33 )
The RPi3B+ found it, and OP listed it in serial devices as /dev/ttyUSB0 , vendor 1a86, product 7523. I assigned it to Kplex with a unique name, running I/O= out, at 4800 baud. I identified the two NMEA wires in the accessory bundle of the Standard Horizon VHF, and connected them to the dongle. At first I had the polarity reversed, and nothing happened. I tried it the other way 'round, and, voila! The gps position appeared on the VHF screen. The data moving through the dongle included an unfiltered mix of GP, AI, and AP sentences, and this did not seem to adversely affect the connection to the radio.
I had planned to try using the same dongle out to send autopilot instructions to a Raymarine 'Radio Navigation Interface' (part Z075), but I've been unable to locate any substantial wiring information for the device. That's a subject for a different thread!
I hope these notes are helpful!
(From Amazon, ~$7, https://www.amazon.com/JBtek-Converter-A...27KYJ19G33 )
The RPi3B+ found it, and OP listed it in serial devices as /dev/ttyUSB0 , vendor 1a86, product 7523. I assigned it to Kplex with a unique name, running I/O= out, at 4800 baud. I identified the two NMEA wires in the accessory bundle of the Standard Horizon VHF, and connected them to the dongle. At first I had the polarity reversed, and nothing happened. I tried it the other way 'round, and, voila! The gps position appeared on the VHF screen. The data moving through the dongle included an unfiltered mix of GP, AI, and AP sentences, and this did not seem to adversely affect the connection to the radio.
I had planned to try using the same dongle out to send autopilot instructions to a Raymarine 'Radio Navigation Interface' (part Z075), but I've been unable to locate any substantial wiring information for the device. That's a subject for a different thread!
I hope these notes are helpful!