Recently I decided to make better DIY controllers for my EQ6 and LXD75 mounts...
The requirements are as follows in order of priorities:
1) low cost and simple, no nonsese design.
2) must have handpad, for quick and fine positioning
3) guiding port (must be)
4) Connectivity to CdC or other PC planetarium software (nice to have but not mandatory)
I altready had my own hand-pad controller, based on 68HC705 processor, which I was using for the last couple of years for AP on my permanent mount. The tracking accuracy was excellent, the only drawback with this system was the lack of connectivity with CdC (this is basically just a dumb software-implenented timer, outputting a step pulse every 15ms for tracking and every 100us for positioning), and when I needed GoTo (on very rare occasions) I was using SoundStepper.
My LXD75 controller is "Duo", similar in functionality to my own controller (tracking, 1x, 8x, 32x slew on both axes), but because of large PE MT-1 motor with gearbox), I decided to replace the final gear transmission with timing belt 5:1 transmission.. and that meant different timing => new controller (or hacking firmware. Or different crystal.. definitelly not the low cost solution).
Arduino board seemed to be a good and universal platform for more clever controllers.. So I had a look at AstrEQ and ONstep solutions, based on arduino:
http://www.stellarjourney.com/index....uipment_onstep
http://www.astroeq.co.uk/tutorials.p...hp?id=buildown
As they are at the moment, neither of those approaches are ideal (to my taste).
ONstep requires Android smart phone and BT connectivity to initialise and start tracking with hand pad emulated by android app.There is no app for Windows...
When connected to CdC (via USB, using ASCOM driver) there is a limitation to sync functionality (after manual move of the telescope - the author told me fimware can't sync on anything further away than 30 degrees or so... I didn't ask why yet).
Guiding is possible via ST-4 port or via serial (LX200 protocol), I tested it and it worked fine with K3CCD.
AstroEQ works via ASCOM driver only (USB port), and it doesn't even start without it.
It has ST-4 port... and no handpad.
I asked the author about stand-alone.. and he told me he is working on the hand pad right now, the code will be available for testing in couple od days... So if this works out OK, AstroEQ will be the ideal solution for me.
I will place arduino Mega board in handpad box, equipped with push buttons and necessary connectors. The motor drivers (accepting STEP and DIR pulses) are already in the mount.
This solution is very flexible:
It will work as stand-alone, with or without handpad, with or without computer.