reprap.me stepsticks and Gen7 ?

Hello,
I just received 2 StepStick boards from reprap.me A4982 to replace one A4983 broken one from ebay.
And guess what, they both don't work on my GEN7 1.41 board. They get hot an the motor gives some noise, that's all.
Changing the current did not solve the issue. The A4983 based china work well. So has anyone a clue what the differnce might be ? Both chips should have the same timing, the only differnce I found so fas is the stepping configuration.
At least reprap.me says they should work on RAMPS and Sanguinololu. The differnce I found is that RAMPS and Sanguinololu use Pull-Down on MS1 and GEN7 has only Pull-Up.

Any tip ?

Thanks

Michael

Hello,
I tested to use same Pull-Down as on Ramps and RAMPS and Sanguinololu,
so I guess this is either a firmware (Teacup) issue with these so called stepstick, but I guess they are just crab.
There is no schematic and printed on the board is [reprap.org] which is a complete different chip.
So no schematic for these boards.

cu

Michael

Quote

The differnce I found is that RAMPS and Sanguinololu use Pull-Down on MS1 and GEN7 has only Pull-Up.

That's true, Gen7 hardwires MS1 to high to save a resistor and a jumper (prohibiting only full-step and quarter-step mode on the A4983/A4988). Everything else is the same.

Looking at the data sheet, the A4982 doesn't have MS3, to they obviously had to make assumptions on how to deal with the missing signal. Without a schematic, solutions can be only guessed. To join the recent MakerBot discussion: closed source is bad! (for the user)

One thing I don't see yet is: why are people going away from the A4983/A4988 (which are truly compatible to each other) to this A4982? reprap.me is not the only one who does.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Traumflug Wrote:
-------------------------------------------------------
> One thing I don't see yet is: why are people going
> away from the A4983/A4988 (which are truly
> compatible to each other) to this A4982? reprap.me
> is not the only one who does.

The TSSOP package is easier to solder.

Hello,
not so sure with the pad in the middle and the via required to get the cooling.
But all this does not explain why they make so much trouble, is there a timing differnce, I did not find anything in the data. From the data sheet I can't figure out any real difference. So either the reprap.me design is differnt from the stepstick or there must be a simple solution to get this resolved.
Is there any way in teacup to reduce the step frequency ? Does the timing match the requirements ?

Thanks

Michael

Quote

Is there any way in teacup to reduce the step frequency ?

Command a slower movement. That's all.

Quote

Does the timing match the requirements ?

Yes, because the timing is given by the requested movement speed, not the stepper driver circuitry. Some stepper driver chips like the Toshiba TB6560 are known to require a long pulse (which Teacup provides), but the frequency of the pulses always matches the frequency of the motor steps. One pulse -> one motor step.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

Hello all,
I at least get some noisy movement from the Y-Axis motor using the reprap.me driver under repetier firmware....
It looks that these so named stepstick can't deliver the required current at the end....
The A4988 based work fine on that axis.
So as long as I don't get the schematic with the used resistor values, I will send them both back to Denmark.
I payed by paypal and so I hope to get my money back, as these so named StepStick don't work as described.
I now know why the seller offers them with "Free heatsink for more power and better performance".

So anyone buying these should make sure that he does not use common 1.7A motors. These stepsticks don't get that current done. I guess reprap.me uses low current motors to test.

@Traumflug, there is some diffence obviously how Teacup drives the motors differnt than Repetier does.

Thanks

Michael

Quote

there is some diffence obviously how Teacup drives the motors differnt than Repetier does

Hardly believable. A pin can be either high or low and changing between these two is what all firmwares do. Well, if Repetier works better for you, use that.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

I don't know what the problem is either, could be design or build problems, but people do seem to have a lot of trouble with the boards from reprap.me.

Hello,
I now received 2 original Pololu drivers and they behave the same ;.( So I exchanged now one stepper 1.7A by a low current one 12V, 0,4A and it moves ;-(
So the original and the reprap.me one seem to not allow as much current as those I bought from china.
So I ordered some spare in china and will wait to get some more information regarding the difference.

reprap.me was quite friendly as I got my money back after returning the for me useless devices.

I'll try to sched some more light on these differnces as soon as I get my prusa printing.

cu

Michael

Quote
Traumflug
That's true, Gen7 hardwires MS1 to high to save a resistor and a jumper.

Sorry for Hijacking this old Thread. But does that basically mean, that i have to add a Jumper for MS1 and a Resistor to it ( Like on Sanguinololu 100k to GND ).
And leave out the trace from MS1 to the 1k Resistors connected to 5v.