A.6 Q-Channel interface for power signals

The Q‑Channel interface for power processes all Q‑Channel power control signals.

The following table shows the signals that are used by the Q‑Channel interface for power.

Table A-6 Q‑Channel interface for power signals

Signal name Direction Source or destination Description
qreqn_pwr Input Power Policy Unit (PPU).

Quiescence request. Active‑LOW.

Synchronized with double‑flop synchronizer.

qacceptn_pwr Output PPU

Accept quiescence request. Active‑LOW.

Isolation and reset value = 0b0.

qdeny_pwr Output PPU

Deny quiescence request. Active‑HIGH.

Isolation and reset value = 0b0.

qactive_pwr Output PPU Activity indication. Active‑HIGH.

Driving signals

The system PPU might be in a different clock or power domain to GFC-100. Therefore, the Q‑Channel interface for power is considered to be fully asynchronous. This means that a double‑flop synchronizer captures the input signal. Registers drive all output signals.

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