Bob,
Here is how you access CAT over the K3 Twin setup:
Note first that in a "Twin" configuration, COM2 is used to "tie" the two ends together and carries the CAT data. In order to access CAT, you need to get to COM2 without touching it. The easiest method is to duplicate COM2 over COM1 using a function in the RRC as follows:
- Change both RRC's COM1 to mode-7. Note that the baud rate does not have to be identical with COM2 to fit a lower bandwidth or software requirement.
- If using a "real" serial cable:
- connect between the control RRC's COM1 and the PC, but note that the pinout is not the standard straight-through serial port. Use the pinout description in the RemoteRig manual, or just try a null-modem cable which usually works (may need a gender changer).
- The serial setting for COM1 "Use USB Com Port as COM1" must be set to NO
- If using USB:
- make sure that first Microbit Setup Manager is installed first on the control PC to get the drivers.
- Then change the serial settings for COM1 to change "Use USB Com Port as COM1" to YES
- connect the USB cable between the RRC and computer and wait for the drivers to finish installing
- go to the Windows Device Manager and look at which virtual serial port was assigned to COM1 and use that for your software, taking the correct baud rate into account.
Note also that you can pull CAT data in parallel off of the radio RRC to use a PC on that end, or to sync with a remote device (amplifier, SteppIR, etc.)
I hope this answers your question.
73,
Mitch DJ0QN / K7DX