DESR DVR Reference

DESR DVR: discovery and launch contract

Off by default. With Game Sources > DESR DVR ISOs (experimental) on, the HDD page checks the DVRP capability bit (SPD_CAPS_DVR). Only a PSX DESR has it, so ordinary PS2 models never load a module or touch a partition. On a DESR the page loads dvrdrv and dvrfile once, mounts dvr_hdd0:__xcontents and __xdata read-only as dvr_pfs0:/dvr_pfs1:, and lists the .iso files in their root, /DVD and /CD folders after the HDL rows. A failed or truncated scan keeps the last-good rows. Nothing is ever written, created or formatted on a DVR partition. NOT TESTED on DESR hardware.

Before a DVR row tears down the GUI, it must call sysNeutrinoPreflight and sysNeutrinoArgsPreflight with the same launch values. The preflight requires config/bsd-dvr.toml or adjacent bsd-dvr.toml, followed by modules/dvrdrv.irx, modules/dvrfile.irx and modules/dvrfile_fhi.irx, beside the selected Neutrino ELF. Every successful read-only probe is closed. Missing files, missing directory separators and overlong paths refuse the launch while the menu is still available.

DVR must use the companion's PSX-mode transition. Active -qb is refused. Active -bsd= and -bsdfs= overrides are also refused for DVR: the launch owns its filesystem backend, and forwarded user tokens must not silently replace it with a block-device configuration. Disabled $- tokens and options after --b retain the existing parser semantics; global and per-game option scopes remain independent. Other transports retain their existing behavior.

The argv builder emits -bsd=dvr and the supplied dvr_pfsN: path, ignores the filesystem picker for this backend, and adds neither quickboot nor PS2 logo. Argument count/byte-budget refusal still applies before teardown.

The normal bundled Neutrino is not a DVR companion. File presence is only a preflight check; it does not authenticate a companion build or establish module ABI compatibility. A matching DVR-capable companion and its PSX reset behavior must be validated during the later platform port and on DESR hardware.

The installed ps2build SDK has dvr and dvrfile driver packages. That does not establish that their binaries can replace a companion's game-side IRXs. The custom PCCF driver sources are a separate application port. No SDK deficiency has been confirmed by this launch-contract work.

Related guide: PSX DVR.

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Source: docs/DESR-DVR.md @ b4c23bdac8f9.