OCX160 Datasheet, PDF (9/44 Pages) List of Unclassifed Manufacturers – OCX160 Crosspoint Switch

OCX160 Crosspoint Switch—Preliminary Data Sheet
1.1.2
Broadcast Mode
The OCX160 has a special Broadcast Mode which connects any input to all outputs without
performance degradation. The input is selected using RapidConfigure or JTAG and disconnects
all other inputs. The Global Update pin (UPDATE#) must be held high during Broadcast Mode.
Asserting the UPDATE# pin returns the array to the previous program condition.
1.2 Output Buffer Configuration
Every output port of the OCX160 can be configured as either a flow-through or registered output. In
registered mode there are two clock sources that are available:
• Global Clock
• Next Neighbor
Additionally, there are output control signals.
1.2.1
Output Control Signals
Every output port of the OCX has a global Output Enable signal (OE#). All output buffers have
output enables that have programmable polarity and are individually configurable.
Additionally each output can be permanently enabled (always ON) or disabled (always OFF)
which is useful for applications which need to tri-state outputs (for example when using multiple
chips in expansion mode) or for power saving in designs that do not need to use all the outputs
available.
Two control bits are used to control the function of the output enable function as described in
Table 5.
1.2.2
Neighboring Output Port as a Clock Source
A physically adjacent port can be used as a clock source for an output port configured in
registered mode. These outputs are grouped in pairs such that the signal being switched through
OUT0 can be used to clock the signal being switched through OUT1, and vice versa. Any single
clock or data input signal can be used to clock any other input signal provided they are switched
to an appropriate output pair (see Table 2). Figure 4 shows the implementation of next neighbor
output port clocking in the OCX160 switch.
For example, INx is used for data input while INy is used for the corresponding clock. INx is
connected to OUT0 via the crosspoint array while INy is connected to OUT1 via the crosspoint
array. OUT0 is configured in registered output (RO) mode with OUT1 as its next neighbor clock
selection. OUT1 will output the clock signal as well as clock the data in OUT0. Adjacent port
selection is required for next neighbor clocking in the registered output mode.
This feature is useful in many applications where different types of data switching through the
crosspoint array have various associated clocks. To match the delays in the data and
corresponding clocks, it is common practice to pass the clocks through the switch along with the
data.
I-Cube, Inc.
[Rev. 1.6] 2/20/01
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