Platform Cable USB II
X-Ref Target - Figure 30
(A)
(B)
(C)
(D)
(E)
12 Mb/s Bus Speed
12 Mb/s Bus Speed
480 Mb/s Bus Speed
480 Mb/s Bus Speed
480 Mb/s Bus Speed
1.X Root Hub
1.X Root Hub
2.0 Root Hub
2.0 Root Hub
2.0 Root Hub
500
mA
500
mA
500
mA
500
mA
500
mA
Power
Power
2.0 External
Bus-Powered
Hub
2.0 External
Self-Powered
Hub
2.0 External
Self-Powered
Hub
Platform Cable
USB II
Platform Cable
USB II
Enumerates at
full speed because
root hub only
Enumerates at
Hi-Speed — best
performance due to
high bus speed.
< 500
mA
< 500
mA
500
mA
operates at full
speed — degraded
performance due
to slow bus speed
Platform Cable
USB II
Platform Cable
USB II
Platform Cable
USB II
Enumerates at
full speed because
root hub only
Enumerates at full speed
because 2.0 external
hub operates at full
speed — degraded
performance due to slow
bus speed. Cable may
not enumerate.
Enumerates at
Hi-Speed — best
performance due to
high bus speed.
operates at full
speed — degraded
performance due
to slow bus speed
DS593_30_021408
Figure 30: Platform Cable USB II Performance with Various Hub Types
Interface Pin Descriptions
Table 6: JTAG/SPI/Slave Serial Port: 2-mm Connector Signals
MODE
SPI
Pin
Number
Direction(2)
Description
JTAG
Slave-Serial
Configuration Programming(1) Configuration
Target Reference Voltage(3). This pin
should be connected to a voltage bus on the
target system that serves the JTAG, SPI or
Slave Serial interface. For example, when
programming a CoolRunner-II device using
JTAG, VREF should be connected to the
target VAUX bus.
2
VREF
VREF
VREF
In
JTAG Test Mode Select. This pin is the
JTAG mode signal establishing appropriate
TAP state transitions for target ISP devices
sharing the same data stream.
4
TMS
–
–
Out
JTAG Test Clock. This pin is the clock
signal for JTAG operations and should be
connected to the TCK pin on all target ISP
devices sharing the same data stream.
6
8
TCK
TDO
–
–
–
–
Out
In
JTAG Test Data Out. This pin is the serial
data stream received from the TDO pin on
the last device in a JTAG chain.
DS593 (v1.2.1) March 17, 2011
www.xilinx.com
29
XILINX [ XILINX, INC ]
