Timestamp Unit Interface Signals

The timestamp unit (TSU) clock signal can be sourced from the LPD clock controller, an MIO pin, or a EMIO port interface signal. The TSU clock is programmed using the registers listed in System-Level Registers. There is one clock shared by both GEM controllers.

The CTRL signals control the incrementing of the timer. The timer increments:

• 00: based on the gem_tsu_ms value
• 01: by an additional nanosecond
• 10: by one nanosecond fewer
• 11: normally