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Hardware Oddity MCPX Boot Overlay
Evidence: Xbox observed in Bunnie's experiment notebook. Bunnie's original Xbox notes retain an early boot-decryption interpretation and explicitly mark it wrong. Replacing the top boot bytes in all four external-flash copies with NOPs did not prevent booting; the MCPX overlay explained why those flash bytes were not the executing code.
Preserve the experiment, the original interpretation, and the later retraction as separate records. A flash dump or disassembly is not interchangeable with a bus-observed instruction fetch.
Proposed test: trace reset-vector mapping and the overlay-disable transition separately from external-flash contents. Record which device supplies each fetch rather than inferring execution from a static image.
See also Firmware, Boot & ROM and Memory & DMA.
DSP tooling guide and navigation updated November 2, 2026 for experimental PR #384, source 8f51d237. Capture/replay usage and limits.
The earlier wiki-wide review was published November 1, 2026. Emulator source: b7140848. Reviewed wiki content: 1d2b671. Current status · Release availability · Publication process.
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