Hi all, I use Arduino uno with motor shield Pololu. Programmed with DCC++ base station software and communicating via DCC++ controller. All works well. The one problem I have is that the current feedback is not working, I can't see any current drawn on the screen. I understand that the current feedback is done via A0 & A1 pins, do I need to use a resistor on motor shield before the signal goes back to Arduino Uno? Could you please advise. Thank you. Rudolf.
Hi, first: did you connect the FB from the motor shield to A0 on the arduino? second: IMHO I think they made an error on the conversion factor for the pololu board. in motordrivers.h I suppose it should be 9.3 instead of 18 (lines 34 & 35) third: if that didn't help: can you measure anything on the FB pin to gnd when some trains are in operation?
The DCC++EX documentation https://dcc-ex.com/reference/hardware/motor-boards.html does not recommend this motor shield, due to problems with the current feedback.
Hi, to put it right, there is no "not recommended" to read anywhere. Instead I find the pololu MC33926 under "Boards currently supported / Easy to use boards". Only a remark (3A - current sensing is not appropriate for most programming) limits its use for programming. BUT that is based on the problem (low resolution) I try to give a hint for possible fix - obviously no one is interested, so am I now. Instead stay with the obsolete boards or add complexity with additional sensing boards - to each his own. It is the same as with 28 speed steps - a simple patch to be in line with NMRA standard minimum requirements, no one seems interested, so am I now (works for me).
