Hi, I bought a used Rat Rig StrongHold that ran fine for the previous owner. I re-flashed a fresh Flexi-Pi image and now I’m stuck. Setup: • Rat Rig StrongHold, Flexi-HAL (STM32F4, SPI), Raspberry Pi 4• LinuxCNC 2.9.8, QtDragon_hd 1.5• remora-flexi config (~/linuxcnc/configs/flexi-hal/)• Gantry: TWO Y motors (joint.1 + joint.3), but only ONE Y limit sensor• Sensors: Heschen SN04-N2 (inductive, NPN, NC) Problem: • Status shows “hard limits tripped”, machine won’t turn ON• HOME X / HOME Y / HOME Z read as triggered (red) permanently in the INPUTS panel, machine sitting free in the middle• The separate “LIMIT” input does NOT light up Key finding — this is the important part: • If I DISCONNECT a limit switch, NOTHING changes — the home input stays triggered.• So the input reads as permanently active regardless of whether a sensor is connected or not.• Toggling .not on the home-sw-in lines in the HAL does nothing either. Commenting the lines out completely also changes nothing.• The sensors themselves work fine (LED on sensor and breakout board switches with metal, they have power). I did NOT change any wiring — it’s exactly as it ran for the previous owner. So it seems the inversion/logic is not on the LinuxCNC side at all. My question: Where does the limit/home input polarity get set for the Flexi-HAL? Is it a grblHAL firmware setting on the board itself (like $5 invert limit pins, or an NC/NO setting), separate from the LinuxCNC HAL/INI? If so, how do I read and change it — through LinuxCNC, or do I need to connect to the board another way? Since disconnecting the switch doesn’t change the input at all, I suspect the board is configured to expect the opposite switch type (or the pins are inverted at the firmware level). Also (probably separate): MODBUS ERRORS counter keeps climbing (was ~174, rising), FAULT 0x0 — that’s the VFD/RS485 side (vfdmod, set for Durapulse GS10 by default). Happy to post photos of the board, breakout PCB, INPUTS panel, and my full HAL/INI. Thanks a lot!
