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Old 28-01-2016, 06:39 AM
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bojan
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Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 6,932
Ken,
Thank you for sharing the code, the comments are full of information :-)
MT-1 motors (from LDX75) have 20ohms coils, and are used as bipolars.. however they are actually unipolar (6 wires, but only 2 half-coils are connected to DIN connector.. and there are enough unused pins for the rest od wires to be connected) so they can be driven with ULN2003 as well (DUO controller has 2 H-bridges for each motor).

When I was modifying my EQ6, I decided to have microstepping drivers inside the mount, so the circuitry that generates timing can be part of hanpad.
I even have 15ms timing generator placed inside DSUB15 connector housing, without anything else.. to be used for most basic mount operation (tracking only).
This way, I can use Bartels, SoundStepper.. whatever is suitable for that particular moment.

However, there is one problem with this particular implementation (or the way I did it) - the microstepping settings are in a form of jumpers insie the mount.... This is fine for Bartels, SoundStepper, ONstep (for now) but not OK for AstroEQ, which dynamically controls the microsteping mode of each motor, in order to achieve optimal torque and slew speed.

As for my LDX75, I designed a small board that holds only Pololu-style driver, and I was tempted to place them in each motor housing, to standardise the interface..
The similar driver boards are available on ebay:
http://www.ebay.com.au/itm/DC9-24V-M...YAAOxy0x1TWANj
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Last edited by bojan; 28-01-2016 at 08:56 AM.
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