Specifications

PCIe/104 and PCI/104-Express Specification Revision 3.0 February 17, 2015 Page 18
2.4.5 Link Shifting PCB Examples
As a demonstration of link shifting in the presence of multiple link groups, the x1 PCI Express, x4 PCI Express, USB 2.0,
USB 3.0, and SATA link groups are used in Figure 2-3: Automatic Link Shifting Examples for Host and Various
Devices. Any Device may use one or more Links from any group. If multiple Links are used then the necessary link
shifting must be implemented on the Device PCB for each Link and Link Group. For example, in the case where two x1
Link devices are resident on the Device, it is required that the remaining two unused Links be shifted two locations in
order that other Devices be able to use the remaining Links. It is not enough to shift only one link space as in the case of
a one x1 Link Device.
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
USB Device
Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
x1 Link Device
Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
Two x1 Link Devices
Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
x4 Link Device
Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
Combination x1 and
x4 Link Devices
Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
SATA Device
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
Host Module
0x1 1x1 2x1 3x1 0x4(0:3) 1x4(0:3) USB0 USB1 SATA0 SATA1
Figure 2-3: Automatic Link Shifting Examples for Host and Various Devices