42.6.1.4.3 Escape Mode
Escape mode is a special mode of operation that uses the data lanes to communicate asynchronously using the low-power states at low speed. A data lane enters Escape mode through an Escape mode entry procedure (LP-11, LP-10, LP-00, LP-01, LP-00). If an LP-11 is detected before reaching LP-00 state, the entry is aborted and the receiver returns to the Stop state. Once the sequence is correctly completed, the transmitter sends an 8-bit command to indicate a requested action. The table below shows the actions supported by Escape mode. If the entry command is invalid, the PHY_ERRESC_x error flag goes high, and the receiver waits until the transmitter returns to the Stop state.
| Escape Mode Action | Entry Command Pattern (First Bit to Last Bit to be Transmitted) |
Command Type |
|---|---|---|
| Ultra-Low-Power State | 0x1E | mode |
| Reset Trigger | 0x62 | trigger |
| Low-Power Data Transmission | 0x87 | mode |
Low-Power Data Transmission (LPDT)
In LPDT mode, the data can be received on the lines at low speed in Low-Power mode. High-speed receivers are off and low-power receivers are on. During LPDT, the protocol can pause by maintaining a Space state on the lines.
Remote Trigger
Remote Trigger mode allows the protocol to send a flag to the receiving side at the request of the transmitting side.
In Escape mode, the RXCLKESC can stop at anytime in either Low or High state.
Ultra-Low-Power State (ULPS)
Ultra-Low-Power State (ULPS) mode has the lowest power consumption, excluding the Shutdown mode.
For data lanes, this mode is entered by sending an ULPS entry command, after the Escape mode entry command. During this mode, the lines are in the Space state (LP-00). Although the clock lane does not support regular Escape mode, the clock lane supports ULPS.