This command links to the previous PGC within the same domain and optionally highlights a specified menu button. A button value of 0 indicates no highlight. PGCs within a domain are numbered from 1. In the title domain, each PGC is mapped to a title number and can be accessed from the VMG or another VTS or VTSM domain via the entry PGC of the specified title. Each title has only one entry PGC and only this PGC can be accessed directly. To access other (non-entry) PGCs in the title from a different domain, virtual commands must be present in the precommand section of the entry PGC to route access requests to other PGCs in the same title.

The DVD specifications support a maximum of 999 PGCs per VTS and up to 36 highlight buttons per display menu. For practical purposes, most authoring packages limit a VTS to 256 PGCs or fewer.

LinkPrevPGC can connect two arbitrary PGCs together so that when one PGC completes playing, the other PGC plays again automatically. The PGC data structure has a PrevPGC field to define any PGC in the video title set domain as the previous PGC. This can be used to take advantage of the functions built into the DVD remote control. The Prev button on a DVD player's remote control directs playback to the previous PGC that is connected to the current PGC via the PrevPGC field.

Cells having cell commands are non-seamless by default. LinkPrevPGC can be present only in cell or button commands. LinkPrevPGC cannot be present in the First-Play domain.

Link to previous PGC in the same domain
LinkPrevPGC   Highlight button
DVD Command	Hex Encoding
LinkPrevPGC,button 0	20 01 00 00 00 00 00 0B

This command can be combined with the Compare GPRM operations for conditional branching. When combining, this command is executed only if the result of the comparison is true.

1) Compare to another GPRM register and LinkPrevPGC
2) Compare to another SPRM register and LinkPrevPGC
3) Compare to a constant value and LinkPrevPGC
4) SetGPRM and LinkPrevPGC