Who would like to review my schematic? I am sure I have missed things. Also pretty sure I have more filtering on the stepper driver motor voltage than is really needed.
All pins with suffix CFG0 to CFG6 have a special meaning in this mode. They are evaluated using tristate detection, in order to differentiate between - CFG pin tied to GND - CFG pin open (no connection) - CFG pin tied to VCC_IO
18.3.1 Using LOST_STEPS for dcStep Operation This is the simplest possibility to integrate dcStep with a dedicated motion controller: the motion controller enables dcStep using DCEN or the internal velocity threshold. The TMC2130 tries to follow the steps.
5.4 dcStep Minimum Velocity Register The automatic commutation dcStep becomes enabled by the external signal DCEN. VDCMIN is used as the minimum step velocity when the motor is heavily loaded. Hint: Also set DCCTRL parameters in order to operate dcStep.
18.3.2 DCO Interface to Motion Controller DCEN enables dcStep. It is up to the connected motion controller to enable dcStep either, once a minimum step velocity is exceeded within the motion ramp, or to use the automatic threshold VDCMIN for dcStep enable.
3.7.3 Reduction of Resistive Losses by Adding Schottky Diodes Schottky Diodes can be added to the circuit to reduce driver power dissipation when driving high motor currents (see Figure 3.9). The Schottky diodes have a conduction voltage of about 0.5V and will take over more than half of the motor current during the negative half wave of each output in slow decay and fast decay phases, thus leading to a cooler motor driver. This effect starts from a few percent at 1.2A and increases with higher motor current rating up to roughly 20%.
In case well defined velocity settings and precise motor chopper operation are desired, it is supposed to work with an external clock source.