Information about the TMC2130 stepper drivers
These instructions apply to using the SilentStepStick TMC2130 stepper driver in SPI mode on OnStep Axis1 and Axis2. If using the TMC2130 it is required that both Axis1 and Axis2 use them. You cannot have, for example, a SSS TMC2130 for RA and a DRV8825 for Dec.
Please review the StepStick Driver Summery to learn about limitations with regard to current handling, voltage, and micro-step mode switching with these drivers.
The choice of TMC2130 version depends on several factors, including whether you are using a specific PCB. In other words, one version of the TMC2130 can work with the MaxPCB and STM32, but will not work fully with the MKS Gen-L board.
The following make, model, and version drivers are known to work as described, use others at you own risk.
MaxPCB, MiniPCB and STM32:
If you are using one of MaxPCB, MiniPCB and STM32, you need the SPI version with the pins down.
The Watterott brand modules distributed through Filastruder or Digikey (v1.0 and v1.1) are always reported to work with the above boards, and are HIGHLY RECOMMENDED for those.
The FYSETC brand TMC2130 v1.2 are available from eBay, AliExpress and Amazon with pins pointing down are cheaper and available to more countries. This version has been verified to work.
Note: There are ways to get the FYSETC v1.1 to work with a MiniPCB, MaxPCB, or STM32. You can un-solder, and remove, the UP pins and resolder them to be DOWN instead. This requires a relatively advanced soldering skills and the proper tools available.
As we make it clear above, we recommend that you use v1.2 since there is no extra work involved and therefore it is not as error prone.
MKS Gen-L and RAMPS:
For the MKS Gen-L and RAMPS, the TMC2130 mentioned in the previous section (MaxPCB, ...etc) will not work.
Instead, you must use the FYSETC TMC2130 v1.1 on eBay and AliExpress and come with SPI enabled, and the pins pointing up. The package also includes jumper wires that you will use according to the Wiki page on the MKS Gen-L.
The FYSETC TMC2130 v1.0 modules are not recommended, since they come with SPI disabled, and OnStep can only support TMC2130 that have SPI. Some members were able to get these to work in SPI mode after de-soldering a jumper, and soldering two connections. This requires fairly advanced soldering skill since the jumpers are really tiny. Here is a photo of the driver after modification. There may be other brands and variations out there so be sure to read-up on the brand you end up with!
- TMC2130 stepper drivers have somewhat more limited current handling than, for example, a TI DRV8825. This isn't a problem for the typical OnStep user but it's often a good idea to choose stepper motors which the TMC2130 can fully power, such as ones with a current rating of about 0.9A. It's ok (and sometimes desirable) to pick stepper motors with a higher current rating (which will likely be capable of higher RPM's vs. a lower current rating stepper) but be aware that the TMC2130 might not be able to fully power them and this should be taken into account. If you already have 1.8A to about 2.5A rated stepper motors it might be a good idea to test the S109 stepper driver since it has the best current handling in this "step stick" class of stepper drivers.
- Using these SilentStepStick drivers be aware that there's a power up sequence requirement: "When using an external supply, make sure, that VCC comes up before or in parallel to 5VOUT or VCC_IO, whichever comes up later." I design my controllers (MiniPCB and MaxPCB) so they can't be powered from a USB connection and the stepper motor supply provides VIO to satisfy this requirement. There are also SilentStepStick Protectors available on eBay that solve this problem for other hardware (like a MKS Gen-L for instance.)
- The older Pololu A4988 stepper driver module often serves as an example of how to wire one of these drivers up should you want to design/wire it yourself instead of using a RAMPS, MiniPCB, MaxPCB, etc.
- The Watterott drivers have extensive documentation, etc.
- Note that the FYSETC TMC2130's seem to have silkscreening over the heatsink contact area so that might lower the thermal dissipation a little vs. the Watterott modules.