The downside is that you will have to tune the PID settings using a screwdriver with the Gecko drive's potentiometers, and can only tell what is going on using the LEDs and audible oscillation. Very different from being able to use halscope!
You can use halscope, but it does require having differential output encoders and a Mesa board with encoder inputs, and very good knowledge of wiring/powering stuff as Gecko has its own power for encoders and so does Mesa, making sure those are at the same 0/zero/gnd/potential is absolutely important, and using the +5V only from Gecko to power encoders.
So not easy/comfortable/possible always.
You are correct that you can still use HALscope with the Gecko drives, however if you already have the hardware that can deal with interfacing the encoders to LinuxCNC, then why aren't you just using that setup permanently? It's much easier to tune the PID from the "calibration" dialog within LinuxCNC, rather than use the potentiometers on the Gecko drive.
Mesa cards support single ended encoders via jumpers, but the Gecko drive
only supports single ended not differential. You can simply use half the differential signals to effectively look single ended, however you lose the noise immunity if they are run a long distance (through the drag chain from the motors). This is why I am suggesting the use of the ENCY encoder repeater, so that it takes in the differential signal and cleans it up into a new differential output, where you can opt to use only half the outputs as single ended. You can send the repeated signal to the Gecko drive, and possibly the secondary repeated signal to a Mesa card if present for tuning purposes. Again, I would instead forgo the Gecko drive and just use a Mesa card (or my kit)!
