On-board control procedures for autonomous alignment of science production and hardware compression for the PLATO Mission

The PLATO mission requires twenty-four Normal Cameras (NCAMs) to operate coherently for high-precision photometry. To prevent data stream corruption, the Instrument Control Unit (ICU) must align data production to a strict 6.25s acquisition slot. This paper presents a specialized On-Board Control Procedure (OBCP) designed to manage this synchronization. We describe the nominal start-up sequence, utilizing a reference NCAM event to trigger simultaneous observation and hardware compression, ensuring phase coherence. Furthermore, we detail the autonomous FDIR logic executed following an ICU reboot at the L2 Lagrange point. This sequence restores the Payload Configuration Vector (PCV) and re-initializes N-DPUs to re-establish valid data chunking without ground support. Implemented via interpreted OCL scripts, this architecture allows for dynamic decision-making and in-flight updates. We demonstrate how this flexibility ensures robust fault recovery, minimizing scientific downtime.