Visible to Intel only — GUID: wja1698271776784
Ixiasoft
Visible to Intel only — GUID: wja1698271776784
Ixiasoft
4.20. Precision Time Measurement (PTM) [F/R-Tiles Only]
Precision Time Measurement (PTM) enables precise coordination of events across multiple components with independent local time clocks. Ordinarily, such precise coordination would be difficult given that individual time clocks have differing notions of the value and rate of change of time. To work around this limitation, PTM enables components to calculate the relationship between their local times and a shared PTM Master Time, which is an independent time domain associated with a PTM Root. Each PTM Root supplies the PTM Master Time for a PTM Hierarchy.
- Automatic trigger every 10ms - always enabled
- Manual trigger through user input (ptm_manual_update)
- Clock stops or runs at the wrong frequency (for example, when the link speed is changing), or
- PTM is disabled, or
- PTM response times out (the requester restarts the PTM dialogue when the auto-update or manual update start conditions are met), or
- A duplicate PTM TLP is received or a replay TLP is sent (if waiting for a response, the requester waits for 100µs since the last non-duplicate request was sent before allowing a new PTM dialogue to be started).
- +/-50ns for the common clock scheme.
- +/100ns for the separate clock scheme.