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alden
MemberIt’s a fact that homing needs to be set up exactly for it to work. And the switches need to be firing exactly and not picking up spurious noise. All I can recommend is that you start from the beginning and enable on thing at a time.
Disable all axes min and max switches and make sure $st is set NC or NO for your switch config.
Then enable Xmin (or max, if you are set up that way) for homing only. Not homing + limit. See if you can home X. (g28.2 x0). Remember that if homing does not back all the way off the switch with the zero offset you will have problems.
Do the same for Y, and then Z. See if you can home them individually, and in combination.
Only once all homing works go back and enable limits. Or not. See if things still work. Then record your configuration.
MemberThanks for the note note. The v8 does have an RC circuit – which helps the noise. I need to get this on the wiki. Thanks for the nudge.
Alden
MemberPretty much any bipolar (4 wire) or unipolar (6 or 8 wire) motor that draws less than 2.5 amps will work.
The rated voltage is mostly irrelevant as the stepper driver regulates the current regardless of the supply voltage. People get confused when the motor ratings says something like “3.5 volts”, but that just refers to the draw if current isn’t regulated.
The quality of the motors – that’s the question – but you can experiment with that.
Alden
MemberYou might try the edge branch – 377.08
MemberJerry,
We have not ported TinyG to the Xplained board – or any other Xmega boards. We are about to release TinyG version 8 which has the step/dir/enable lines broken out. Also, we are porting to ARM which will open up a lot of other options.
-Alden
MemberIt’s supposed to report immediately. Can you tell me what build number you are running? It’s the $fb value reported in the startup line or via the $fb command.
Thanks
Alden
MemberGood news. Please let us know if you find out why minicom didn’t work.
-Alden
MemberIt should work fine with that motor in either bipolar or unipolar mode. Both draw less than the 2.5 amp max that TinyG can support.
You can drive the motor from a power supply of 12 volts, 24 volts, or up to 30 volts. The motor ratings are not the same as the power supply voltage that you provide to the TinyG board. This is often a point of confusion when selecting motors. We prefer using 24 to 30 volt supplies as opposed to 12 volts. The motors react better and actually run cooler than with lower voltages.
Alden
MemberThis has been fixed and is available in the edge branch, build 377.08
MemberNot sure what’s going on. TinyG needs a standard 115,200 setup
– 115,200 baud, 8 data bits, 1 stop bit, no parity.If you are going to stream to it from the terminal emulator you should also enable XON/XOFF on both tinyg and the terminal emulator.
MemberAt the current time backlash compensation is pretty far down the list – sorry. It’s pretty hard to get right (e.g. the circle test) and there are a number of other things that we’df like to get working first.
MemberOK. This sounds weird. I’ll look into this but probably not until the weekend (being realistic). Thanks for documenting is so well. What build are you running?
Alden
MemberSteppers and encoders are a long discussion. Steppers – run properly – are not supposed to need encoders. If you drop steps and feel the need for an encoder that it’s a symptom of a different problem – the steppers are being run out of their operating envelope. Sensors are essential for servos (of course), and there are some designs for “servoed steppers”, but at that point they are being run as servos, not steppers.
I think if we went the encoder route it would be to support full servos. Servoed steppers also hitch a ride but the design would be for servoed operation.
MemberThe regulator can handle 1 amp (in theory). Most fans are < 250ma, so I didn;t worry about it. A figure of say it’s 500ma max out is probably good and conservative.
The spindle and coolant outs should be limited to 10 ma. These are control signals, so this should not be a problem.
MemberI need to write this up for the wiki. In the mean time, Here’s how Units work.
– All units are in MM in the internal system.
– They are accepted and reported in either Inches or MM units depending on what units are set in GCODE. Issuing G20 sets Inches mode, G21 sets MM mode.
– When you enter new settings they must therefore be entered in the Units mode the system is set to. So you need to be sure you know what mode you are in. Best, set it before you change any configs.–Alden
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