enaiman Any idea why it doesn't stop?
No idea. If you have a USB Protocol Analyzer, you can place it in the serial port route to see if the command is being sent, and if it is the correct command.
If you run macOS, I had written something that includes a protocol analyzer many years ago:
And if you need to command for stopping, just go to my Temma controller:
how do you set the Home Position for this mount?
Home is the "counterweight down, declination 90º" as the home position. Set that position up before powering the mount on and before connecting the mount to ASIAIR. (I personally find the RainbowAstro's "west horizon" home to be the best, since it is also the easiest position to mount the OTA.)
But remember that because of the way the Takahashi polar scope is aligned, that "counterweight shaft" is not always pointed vertically at ground for the "real" home. It can be even 40º off. What you can do is to look through the polar scope and look at something vertical (rope and weight as a plumb, for example) -- loosen the hour angle circle and lock it to 0º, since you won't need that circle for its real purpose when computer controlled. You should be able to use that 0 hour angle as home position afterwards.
Don't need to be that precise, since you can plate solve and sync.
Takahashi actually has a "sync to Zenith" function, which is especially useful in the daytime. Just need a bubble level to get a sync, since there are no stars. ASIAIR does not know how to use that function, as usual. If you check the cocoaTemma manual, I had implemented both that, and star sync. Temma also has a separate command to force set the pier side, so you can use either pier east or pier west to do the sync to zenith. When plate solve was not available, I used zenith syncing even when there are stars.
the mount is tracking by default.
You will find that most mounts implement "turn on tracking after a GOTO."