Revision 1.5
Integrated Device Technology, Inc.
CPS-16/12/8 User Manual
1 - 1
July 10, 2012
Chapter 1
Device Overview
1 DEVICE OVERVIEW
The objective of this chapter is to provide an overview of the capabilities of the CPS device.
1.1 DEVICE DESCRIPTION
The CPS device functionality is optimized for line card and backplane switching. Its primary function is to
switch data plane and control plane data packets via Serial Rapid IO (SRIO) between a set of devices that
reside on the same line card. In addition, it supports the ability to bridge communications between multiple
on-board (or local) devices and a set of external line cards by providing long run Rapid IO backplane inter-
connects. In this manner, for example, the device can serve as a switch between a set of RF cards and a
set of Rapid IO based DSPs in a wireless basestation.
The CPS device supports packet switching from up to 16 ports which are comprised of 16 SRIO Lanes. The
encoded data rate for each of the lanes are configurable to either 1.25 Gbps, 2.5 Gbps, or 3.125 Gbps. The
device supports lane grouping such that both 1x and 4x operation, as defined in the applicable RIO specifi-
cations. In addition, the device supports lane grouping in an “enhanced” mode such that a group of 4 Lanes
can be configured as four individual non-redundant 1x ports.
The CPS device supports the reception of SRIO maintenance packets (type 8) which are directed to it (i.e.
hop count of 0) in support of requirements defined for a RIO switch in the applicable version 1.3 Rapid IO
specifications. The CPS device supports the ability to properly process and forward received maintenance
packets with a hop count >0 as defined in the Rapid IO specifications. With the exception of maintenance
packets, received packets are transmitted unmodified as defined in the 1.3 versions of the applicable Rapid
IO specifications.
From a switching perspective the device functions statically. As such, all input to output port mappings are
configurable through registers. Unless register configurations are changed, the input to output mappings
remains static regardless of the received data (disregarding errors). The switching functionality does not
dynamically “learn” which destinationIDs are tied to a given port by examining RIO header fields and
dynamically updating internal routing tables.
The device supports priority levels 0 - 3 as defined in the revision 1.3 Rapid IO specifications.
The CPS device is programmable by RIO ports, I
2
C JTAG interface.