Anet A8 Marlin BLtouch moves up instead of down during homing I have a previously working Anet A8 that I just flashed to Marlin 1.1.9 (bugfix) and installed a real BLtouch sensor. I followed setup instructions and believe my wiring is correct. When I try to do a G28, the extruder moves to the front left corner properly, then moved to center the BLtouch over the bed. Then, it moves up instead of down, the BLtouch drops the probe, the extruder moves up again, the BLtouch drops the probe again and the extruder moves up again until the carriage is near the top. Using Pronterface I can move the carriage back down, but have to use M211 S0 to let me get it close to the table. X, Y and Z move properly in Pronterface. I have changed the relevant settings in Marlin and recompiled with no success. The BLtouch does it's self test correctly and I can control the probe with commands.
SOLVED -- The problem turned out to be that the BLtouch was set up for 3.3&nbsp;V and my Anet board is 5&nbsp;V. The docs were not clear on what the BL defaulted to and I mistakenly thought 5&nbsp;V. After I did a M280 P0 S140 command, the carriage would home properly with G28. Why it was going up instead of down was a Red Herring. I changed the settings in configuration_adv.h to force 5&nbsp;V and did the EEPROM one time write. Now the A8 works correctly. Thank you for your help Oscar.