Y-stepper problems when using Marlin

[sverd]

Hi @chrissbarr,

after struggling for quite a while my 3D printer is working again, this time with a RUMBA32 v1.0 board. I followed your advice in another topic [https://github.com//issues/35] to get TMC2208 steppers working in UART mode and for most part it works fine now. However, for some reason any stepper connected to the "socket" labeled "Y" does not move at all. Using the M122 to debug the TMC connections indicates no problems at all and also no error message is shown on the grapical display connected to the board. When trying to move the Y-axis everything seems completely fine, but the motor does not move.

When connecting a logic analyzer (SaleaLogic clone) to the STEP and DIR pins of the X-socket and the Y-socket, it turned out that pulses were presented to the STEP pin of the X-stepper (when X-motion was requested) but that the Y-stepper did not get any pulses at all on the STEP line when trying to move the Y-axis. At that point I did not know how to proceed. Is it a known problem?, is something wrong with my Marlin configuration? I'm kind of clueless at the moment.

For this moment I managed to work around it by connecting the Y-stepper to the E2-socket (E1 is already in use for dual Z-steppers), but this does remove the option of a dual extruder and if I'm the only one experiencing this, there is probably something wrong with my setup.

I tried with Marlin 2.0.6.1, Marlin 2.0.7.1 and the debug-2.0.x branch using PlatformIO and all resulted in the same behavior.
Any tip, hint or clue about how to solve this problem is greatly appreciated!