2021-01-01, 09:30 PM
I believe the NASAMarine Duet is the cheapest combined log/depth sounder around but when I ordered it, I quickly found out that it has a major disadvantage: it does not share it's data with other systems, there is no nmea output.
Not content with that, I hacked into the system and added just that, by dropping a tiny Atmega 32U4 board into the case, connecting it to the signal pins for chirp/echo and speed and putting together a quick sketch to wrap it all into valid nmea sentences.
If someone is interested, I can show a bit more of the build
here's the code with very basic documentation: https://github.com/pljakobs/NASAMarineDuetDriver
Not content with that, I hacked into the system and added just that, by dropping a tiny Atmega 32U4 board into the case, connecting it to the signal pins for chirp/echo and speed and putting together a quick sketch to wrap it all into valid nmea sentences.
If someone is interested, I can show a bit more of the build
here's the code with very basic documentation: https://github.com/pljakobs/NASAMarineDuetDriver