Roger Henderson 1ea012aa57 implement FPGA-based CDS to avoid BRAM overflow ... Move CDS phase computation from per-point config storage to FPGA logic. The FPGA now computes the 180° phase shift internally (M/2) and loops twice per point when CDS is enabled. This keeps config memory at 96 bits instead of 112, avoiding BRAM overflow on the Spartan 6. FPGA changes: - Add CDS_ENABLED input to Sweep module (controlled via SPI register 6) - Compute source_phase = M/2 for 180° shift when cds_phase=1 - State machine loops through all stages twice per point when CDS enabled - RESULT_INDEX now includes cds_phase bit: stage[2:0] & point[11:0] & cds_phase Firmware changes: - Add FPGA::SetCDSEnabled() to control CDS via register 6 bit 11 - Update SamplingResult to include cdsPhase field (1 bit) - Simplify VNA.cpp: FPGA handles phase switching, MCU combines results Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>		2026-02-01 21:19:57 +13:00
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FPGA.cpp	implement FPGA-based CDS to avoid BRAM overflow	2026-02-01 21:19:57 +13:00
FPGA.hpp	implement FPGA-based CDS to avoid BRAM overflow	2026-02-01 21:19:57 +13:00
FPGA_HAL.hpp	Test of DFT implementation in FPGA	2020-11-08 14:38:31 +01:00