(2021-01-13, 09:22 PM)Phil_Shotton Wrote: This is very interesting, thank you. Do you think the NASA Depth Gauge works the same way (obvs without the log!)?
I've been trying to build an NMEA output using the secondary gauge connection as described here but the code is much more complicated (not helped by there being no code repository and the code in the atricle being affected by formatting and html escapes. I've built the module and yet to get it to work successfully, not helped by having limited access to the boat due to Covid lockdowns.
Hi!
After reading you, I managed to do the DIY tuto to get NMEA0183 data from the Nasa Clipper Depth and I made some mistakes that I would like to share with you guys, as the authors of the tuto and code writers, Peter Holtermann and Victor Klein ( Thanks, men!) did more than perfect all the incredible work , but the last part ( how to connect it to the raspberry) is not described in the tuto, so I had to suffer some trial-error during my installation, but finally with a happy end..
First of all, use just Original Arduino, not clones. As I am new in arduino, i bought a second hand clone, and I could inject the sketch and it worked,but randomly hung; making me crazy. After many readings, somebody said that clones give weird errors which make you confused as you try all means to fix them when they are just hardware failures. So bought an original new, and worked like a charm.
The second thing is quite risky for the PI integrity and its peripherals; I fried one USB serial converter and left the USB ports hurted and dead in power for several hours and restarts. I switched it off and after a couple of hours, Usb power came back to life. The reason of this risky failure is caused by the fact that the installation done as in the tuto in Openseamap tuto, powers the arduino with the 12V signal fund in the poles of the DIN Cable. And when you connect the USB , then the arduino switches to USB (5V) power source, having to manage 2 different power sources with 2 different voltages. In some clones, the backfeed blocking diode is weak or non existent, allowing the flow of 12V through the USB cable until the Raspberry USB port, damaging it and other plugged peripherals. BE CAREFUL! I was lucky and my Raspberry resurrected, but for several hours, it was like injured...
The solution is quite easy: to the arduino ports, just plug the SCL and SDA poles from the DIN cable , and let it be powered just by the USB cable, only one source of power. Don't plug 12V+ and 12V-.
The rest is easy, create a serial connection with NMEA 0183 output ( Arduino will be detected as an USB serial RS422 converter), and launch it to Signal K with the standard Nmea 0183 bauds rate (4800).
Very cool to have now Depth readings in Signal K!
It's easier to do it than to read it, so don't hesitate to do it, it worths and it is a very cheap improvement for all those like me who have the cheap but reliable NASA gauges ( I do have clipper tactical Wind and CLipper depth sounder)