Xilinx Virtex-5 RocketIO GTP User Manual page 131

R
Table 7-6
Table 7-6: RX OOB/Beacon Signaling Attributes
Attribute
OOB_CLK_DIVIDER
OOBDETECT_THRESHOLD_0
OOBDETECT_THRESHOLD_1
RX_STATUS_FMT_0
RX_STATUS_FMT_1
SATA_BURST_VAL_0
SATA_BURST_VAL_1
SATA_IDLE_VAL_0
SATA_IDLE_VAL_1
SATA_MAX_BURST_0
SATA_MAX_BURST_1
SATA_MAX_INIT_0
SATA_MAX_INIT_1
Virtex-5 RocketIO GTP Transceiver User Guide
UG196 (v1.3) May 25, 2007
defines the RX OOB/beacon signaling attributes.
Sets the squelch clock rate. The squelch clock must be set between 25 MHz and
37.5 MHz, as close to 25 MHz as possible for the SATA OOB detector to work
correctly.
Squelch Clock rate = CLKIN/OOB_CLK_DIVIDER
Valid divider settings are 1, 2, 4, 6, 8, 10, 12, and 14.
Sets the minimum differential voltage between RXN and RXP. When the
differential voltage drops below this level, the incoming signal is an OOB signal.
This 3-bit binary encoded attribute has the following nominal values of the OOB
(1)
threshold voltage :
Value
000
001
010
011
100
101
110
111
Defines which status encoding is used:
PCIE: PCI Express encoding
SATA: SATA encoding
Number of bursts required to declare a COM match. The default for
SATA_BURST_VAL is 4, which is the burst count specified in SATA for COMINIT,
COMRESET, and COMWAIT.
Number of idles required to declare a COM match. Each idle is an OOB signal with
a length that matches either COMINIT/COMRESET or COMWAIT. When the
SATA detector starts to count one type of idle (for example,
COMRESET/COMINIT), it resets the count if it receives the other type. This value
defaults to 3 to match the SATA specification.
Sets the threshold for the SATA detector to reject a burst in terms of squelch clock
cycles. SATA_MAX_BURST has valid values between 1 and 61 (the default is 7)
and must be greater than SATA_MIN_BURST. See the
learn how to calculate the best value for a given squelch clock rate.
Sets the maximum time allowed for a COMINIT/COMRESET idle for the SATA
detector in terms of squelch clock cycles. SATA_MAX_INIT has valid values
between 1 and 61 (the default is 22) and must be greater than SATA_MIN_INIT.
See the "Description" section to learn how to calculate the best value for a given
squelch clock rate.
www.xilinx.com
RX OOB/Beacon Signaling
Description
OOB Nominal Threshold Voltage [mV]
70
85
92
99
105
112
118
127
"Description" section to
131