I soldered and put the jumpers, flashed the arduino mega, it works fine.
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Was it the slp/rst?
yeah. those to pins must be soldered together and some jumpers on the black and white side, 3-4, i don’t remember. The machine is working, without limit switches, with lasergrbl. Ramps 1.6+ is running two nema 17 with one drv8825, fine for the moment, anyway nice board. oh, and cooling for the mega, today stopped working because got hot, forgot about the cooling. Before, i tried to run the cnc with an btt skr 1.4 and marlin 2.0.9,1 and in the and switched to ramps, with grbl firmware it’s much better.
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The function of the sleep pin is to leave the DRV8825 chip in a state of low energy consumption, disabling fundamental internal functions for its operation. Therefore, if it is low, the chip will not work as expected.
The restart pin needs to be at a high logic level for the chip to work, it is a precondition for its operation.
Note that the datasheet states: Low level is for voltages from 0v to 0.7v. High level is in the range between 2.2v and 5.25v. We have between 0.7v and 2.2v a range without logical value determination. This is normally to be avoided.
Therefore, it is not enough to solder the pins together. We have to ensure the logic level high on them. So in addition to this procedure, a wired jumper between them and 5v is necessary, to guarantee the high logic level and prevent it from interpreting the “open” value as a low logic level.
Ok, but it worked though.
