nx_robot_hal.nx

nx_robot_hal.nx -- SOVEREIGN fail-safe hardware-write DRIVER (the HAL the generated firmware binds to). This is the never-brick-critical rung (#26): the layer that actually writes actuator outputs and reads sensors. NEVER-BRICK BY CONSTRUCTION + proven MECHANICALLY by the gate (not promised): * every actuator write is CLAMPED to a safe envelope [HW_SAFE_MIN, HW_SAFE_MAX] before it lands -- no command, however large/negative/malicious, can escape it (defense-in-depth even if the firmware's own clamp were wrong); * pins default to SAFE (0 / disabled) on init; * a WATCHDOG forces an e-stop (all outputs safe) if not kicked; * E-STOP is latched and zeroes every output; * sensor readings are range-checked (out-of-range => invalid => firmware goes safe). Backend here is a MOCK device (an i64 register array) so the whole chain is gate-provable WITHOUT real hardware. HONEST: binding these to a real board's MMIO addresses (the actual GPIO/PWM/step registers) is the final step and needs the bench -- but the fail-safe LOGIC is real + proven now. State layout (i64 array hw): hw[0..HW_NP) = actual pin outputs; hw[HW_NP+p] = sensor[p]; hw[2*HW_NP] = watchdog counter; hw[2*HW_NP+1] = estop latch. license_tier: ORIGINAL expect_exit: 0