Hi,
Pronterface connects just fine, and if I issue commands, the motors just hum. I suppose the frequency is too high. In my test setup, I came up with a max frequency of 14kHz before the motors stall.
Sprinter 1.3.11T / 19.03.2012
RAMPS 1.2, pololu 4983
Temperature of the pololus is good.
Pin assignments are correct: if I do a series of digitalwrites to XYZE_STEP_PIN, the motors move just fine.
Now STEP_DELAY_MICROS and STEP_DELAY_RATIO are not used in the code.
Setting #define _MAX_FEEDRATE {4, 4, 2, 45} this low does not change things either.
How can I reliably reduce the speed or debug this issue?