The arrival of Macs with Apple M1 processors and macOS systems 11 "Big Sur" and macOS 12 "Monterey" had caused disappointments among GPS users connected via USB and/or Bluetooth for their navigation applications..
In USB, Latest DriverProlific V.2.2.2 is now universal for GPS BU-353xx by GlobalSat. As for theGNS3000 (¹) in Bluetooth it always undergoes an instability of the interface for the connection of multiple devices, instability that unfortunately does not yet seem to be fully fixed.
Once the BU-353 is connected to a USB port on the Mac M1 (using a USB-C converter), le nouveau driver crée un port série usbserial-xxxx, qui s’appelle aussi PL2303-USBtoUARTxxxx. Avec l’utilitaire CoolTerm, we can now display the NMEA sentences that are sent by the GPS. I specify that I tested with my "old" BU-353S3 who is more than ten years old, not the most recent BU-353S4 or BU-353N.
But beware, to date only the navigation application MacENCx64 directly recognizes the serial port, by selecting the type = SIRF USB, and displays the position.
Weather4D Routing & Navigation does not read the serial port, because this function does not exist on iOS. Note that the latest version of OpenCPN 5.6.0 for Mac is not given as compatible with macOS 11/12 and does not detect the serial port. However, one can use the trick : [Update 15/02/22 – Read Eric Rodriguez's latest comment at the end of the article].
When it works, it is super ! The GNS3000 is well recognized and the connection can be activated. A GNS3000 serial port is created. On my first try I had no problems, except that the data was only received at the speed of 38400 bps (while the device is factory set to transmit at 4800 bps) :
As for the USB connection, MacENCx64 recognizes the GNS3000 port by selecting the type = Other and flow rate set to 38400.
With Weather4D enabled in the Mac's "Location Service" settings, the GPS position is well received from the GNS3000 :
[Update] With OpenCPN 5.6.0 we must use the same trick as that described by Eric Rodriguez when creating the serial port = /dev/cu. GNS3000 with a speed = 38400. But, once again, incomprehensibly, it may happen that the connection does not establish. Mystery…
There, at least, everything works just fine ! Regardless of the connected Wi-Fi gateway sending NMEA data, with MacENC as with Weather4D Routing & Navigation :
Even with OpenCPN, but beware, a lot of malfunctions could occur with this version not adapted to macOS 11 and later.
Summary, temporaly, there are still fixes to be expected with future updates of the operating system of Macs both in USB connection and Bluetooth. Fortunately, Wi-Fi gateways and multiplexers are becoming widespread on our boats, allowing us to connect to any type of computer and mobile device, to work with our favorite navigation apps.
(¹) GNS3000 Bluetooth GPS Receiver for Mobiles