LDTSTOP# Disconnect Sequence

After a HyperTransport technology disconnect/reconnect sequence, devices that implement the LDTSTOP# protocol are required to update their link widths in exactly the same way as they do after a warm reset sequence. This allows initialization software for systems built from such devices to use the LDTSTOP# protocol rather than warm reset to invoke link width changes. The following requirements exist when during Reset with LDTSTOP#.

  • The LDTSTOP# pin must be deasserted for at least 1 microsecond before RESET# is deasserted.

  • LDTSTOP# must remain deasserted until the link initialization sequence, described later in this section, has completed.

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