Xilinx Virtex-5 RocketIO GTP User Manual

268 www.xilinx.com Virtex-5 RocketIO GTP Transceiver User Guide
UG196 (v1.3) May 25, 2007
Appendix B: OOB/Beacon Signaling
R
In addition to the analog circuitry required to encode and detect the OOB signal state, the
GTP transceiver includes state machines to format and decode bursts of OOB/beacon
signals for SATA (COMRESET, COMWAKE, and COMINIT).
Beacon Signaling in PCI Express
PCI Express uses sequences called beacons to wake endpoints from powerdown states. A
beacon is the transmission of K28.5 (COM) characters. A beacon sequence can have a
frequency anywhere from 30 kHz to 500 MHz.
The PCI Express specification describes the beacon mechanism as an inband wakeup
indication, and defines the use of a discrete wake signal (WAKE#) as an out-of-band
mechanism.
GTP transceiver support for PCI Express beacons uses interface signals defined in the PHY
Interface for the PCI Express (PIPE) Specification. Control logic in the FPGA manages the
format of the beacon sequence.
Figure B-2: SATA COM Sequences
320 ns
106.7 ns
106.7 ns
106.7 ns
COMWAKE
COMRESET
COMINIT
UG196_B_02_092606

Xilinx Virtex-5 RocketIO GTP Specifications

General

Brand	Xilinx
Model	Virtex-5 RocketIO GTP
Category	Transceiver
Language	English