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Hi
I'm still experimenting with the openplotter serial outputs using the pi gpio
i've connected a gps on the gpio serial input using the adafruit tutorial (see my previous post)
Now i'm trying to connect my PC to the gpio serial output ( I use specific navigation software on my PC which cannot use nmea over tcp)
The hardware is simple: an ftdi usb to serial converted connected to GPIO TX end 0
It actually works with openplotter nmea inspector running but stalls if i pause or stop the inspector
any idea's how to fix this
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How do you set this connection on OpenPlotter? I assume you have created a serial output in the NMEA 0183 multiplexer, what is the port? /dev/ttyAMA0?
I do not understand what is the rol of the inspector here
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2016-04-21, 10:28 PM
(This post was last modified: 2016-04-21, 10:30 PM by tkoning.)
hi
I create a serial connection /dev/ttyS0 ,set the baudrate, as an output in open plotter, after that i make a physical link to my PC (from the PI GPIO TX pin via an optocoupler to a serial to usb converter to the pc usb port)
After that I open the usb serial port in open cpn for example
the output from this connection is erratic but becomes completely stable when i start the nmea inspector
I've no explanation for this behaviour
NB on a Pi3 /dev/ttyS0 = /dev/ttyAM0 on a Pi2
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Use a USB serial ttl converter instead of the internal uart1 of the RPi 3. It's a known RPi 3 problem.
As you already recogniced, if there is enough processor usage (inspector) all things are fine. But if the processor change to lower speed (energy saving) the baudrate drops.
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hi
if i use the usb port i cannot connect the pi directly to my PC, except with a usb a-a cable (dangerous), or a usb transfer cable (no experience).
The only hardware solution i can think of is using 2 usb to serial connectors and connecting them with an opto coupler.
pi >> usb to serial >>Tx >>> opto >>> Rx >>usb to serial >> pc
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great contribution e-sailing, you have saved us lot of time and tests