The 35th annual conference on Astronomical Data Analysis Software & Systems 2025 in Görlitz, Germany

The ESA Vigil mission, positioned at the Sun–Earth L5 Lagrange point, is
designed to provide continuous solar monitoring for space-weather forecasting and heliophysics research. The mission’s Photospheric Magnetic field Imager (PMI) acquires full-disk solar images generating raw data rates far exceeding the available telemetry bandwidth. To meet stringent latency and telemetry constraints, PMI implements an FPGA-based onboard processing system that converts high-volume filtergrams into calibrated, demodulated, and compressed science products. This poster presents the front-end stages of the onboard pipeline - the Accumulator and Preprocessing modules, which transform raw filtergrams into calibrated Stokes vectors through deterministic, parallel execution. The implemented system achieves real-time throughput, bit-accurate correctness, and compliance with the allocated FPGA resource budgets.