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[Solved] Configuration for 400 step Motor  

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Hamishi
(@hamishi)
Eminent Member

From the comparison between the 2100 and the 2208 I observe that when the 2100 setting for 1/16 is applied to a 2208 it would probably result in 1/8. 2100 open at cfg1 and cfg2 gives 1/16 <-> 2208 low at ms1 and ms2 gives 1/8.

So there is definitely a difference between the two.

Posted : 09/01/2020 6:47 am
mario
(@mario)
Member Admin

OPEN != GND

I don't know what happens to the 2208 when those config pins are OPEN. This state is not defined. Here is the TMC Datasheet.

https://www.trinamic.com/fileadmin/assets/Products/ICs_Documents/TMC220x_TMC2224_datasheet_Rev1.09.pdf

FYI here is the schematic of the HAT

https://github.com/watterott/RPi-FabScan-HAT/blob/master/hardware/RPi-FabScan-HAT_v10.pdf

As far as i know is the default state for the 2100 on the HAT set to open. But there are onboard jumper (solder) joints which can be used to configure the motor driver. See the pictures below. You should try to set MS1 and MS2 to VIO (5V) for the 2208. This should set the diver to stealthChop 1/16 mode. ( https://learn.watterott.com/silentstepstick/pinconfig/tmc2208/ )

Bildschirmfoto 2020 01 09 um 09.22.46 (3)
Bildschirmfoto 2020 01 09 um 09.22.19 (3)

You should better measure which Cx on the board relates to MSx on the driver. ( I think it is mapped 1:1 e.g C1 -> MS1 but just to be sure you should use a multimeter to measure it)

This post was modified 1 month ago 3 times by mario
Posted : 09/01/2020 8:28 am
mario
(@mario)
Member Admin

Just ordered some 2208 drivers from watterott.

Posted : 09/01/2020 8:33 am
Hamishi
(@hamishi)
Eminent Member

@Mario,

Can you confirm, that these pins are not driven by the software. From your replay above it seems to me that for the 21xx the default values result in the 1/16 configuration. And that for the 2208 these pins should be pulled to Vcc by soldering the bridges. I will check what is actually the case on my 2208.

If they are not driven by the software, I can pull them to Vcc by closing the bridges as indicated in the schematic. Reset the values in the default.config.json and see what happens.

Posted : 09/01/2020 12:44 pm
mario
(@mario)
Member Admin
Posted by: @hamishi

Can you confirm, that these pins are not driven by the software.

Yes. The driver configuration is not software driven. Only hardware. The pads are not connected by default. So the cfg pins are in state OPEN, what fits to the 2100. I need to test the HAT with the 2208.

Posted : 09/01/2020 12:51 pm
Hamishi
(@hamishi)
Eminent Member

So on the FabScanPi Hat  J7 2 and 3 should be closed and J8 2 and 3 should be closed for a 2208 to pull them to 5V.

Posted : 09/01/2020 1:46 pm
mcinerney
(@mcinerney)
Trusted Member

@hamishi

Posted by: @hamishi

So on the FabScanPi Hat  J7 2 and 3 should be closed and J8 2 and 3 should be closed for a 2208 to pull them to 5V.

 

Very good information.  Did you have a chance to test this yet?

Posted : 09/01/2020 2:54 pm
Hamishi
(@hamishi)
Eminent Member

Yes, I just tested it.

Under the driver there are three of these jumper pads, label C3, C2, and C1.

First I verified which of them are connected to MS1 and MS2. It are C1 and C2. I soldered the midpad of C1 and C2 to the 5V pad in order to force the 1/16 mode of the driver according to the documentation. First I did a scan with the 3200 value to see if there was a difference in the scan result and indeed there was, the scan was only over 180 degrees. So then I changed to the 6400 value and the result was a 360 scan.

Summarizing, if one has a 400 step motor and a TMC2208 as stepperdriver the MS1 and MS2 pins have to be connected to 5V by means of bridging the pads C1 and C2 to 5V to force the 1/16 step mode in combination with a value of 6400 in the default.config.json file.

So it is not a software bug but a hardwire bug. I think this should be mentioned in the instructions as apparently my kit came with a 400 step motor and a TMC2208 dirver instead of the 2100 that functions according specs with the pads on the Fabscanpi HAT left open.

For me this problem is solved.

Posted : 09/01/2020 6:03 pm
Hamishi
(@hamishi)
Eminent Member

Thanks to all of you, I think this was a good exercise. 

I also did some modification to the camera mounting as it was not aligned with the table and I put a 3 mm thread rod between the sides of the case in order to ensure better closure of the lid. This because the right side of the case was bent causing a gap between the lid and the side.

Posted : 09/01/2020 6:13 pm
mcinerney
(@mcinerney)
Trusted Member
Posted by: @hamishi

Thanks to all of you, I think this was a good exercise. 

I also did some modification to the camera mounting as it was not aligned with the table and I put a 3 mm thread rod between the sides of the case in order to ensure better closure of the lid. This because the right side of the case was bent causing a gap between the lid and the side.

That is good news! I will test the driver tonight and I did find out I have a TMC2208.  Can you send some photos of your enclosure modification I have the same type of problem.

Thanks very much for your help.

Posted : 09/01/2020 7:03 pm
mario
(@mario)
Member Admin

@hamishi

Thank you for your work! I will add this to the documentation as soon as i can. I think i will find some time at the weekeend. 

Posted : 09/01/2020 7:04 pm
Hamishi
(@hamishi)
Eminent Member
CIMG0707
Posted : 09/01/2020 8:51 pm
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