HDMP-3268 Datasheet, PDF (5/18 Pages) Agilent(Hewlett-Packard) – 3.2 Gbit/sec 68x68 Crosspoint Switch

Control Register
The control register is used to
program the input AC or DC
coupling, input equalization,
output amplitude and power
on/off settings of each input and
output of the crosspoint switch.
To access the control register the
control signal CNTL must be
high. Table 2 gives the specific
definition of each bit in the
control register. Upon power-up,
all bits of the control register are
set to 0.
Table 2. HDMP-3268 Control Register Definition
Bit(s)
6:5
Name
Output On/Off & Amplitude^[1]
Value
00
01
10
11
Definition
Output stage disabled (power off)
Typical Vop^[1] = 550 mV
Typical Vop^[1] = 800 mV
Typical Vop^[1] = 1050 mV
4:2
Equalization Amplitude
000
Input equalization disabled
111
Maximum input equalization
1
Input On/Off
0
Input stage disabled (power off)
1
Input stage active (power on)
0
AC/DC
0
DC input coupling
1
AC input coupling
Note:
1. Output Peak-to-Peak Differential Voltage, Vop, is specified as DOUT+ minus DOUT-. This measurement is made using a repeating 1010 pattern
with a 100 Ω termination resistor across the DOUT+ and DOUT- outputs. The swing doubles if there is no termination resistor.
Switch Matrix Configuration
The address registers are used to
program the connectivity of the
switch matrix. The address
registers are accessed when the
CNTL input is low. There are two
independent banks of 68 address
registers to allow one bank to be
programmed while the other bank
is controlling the switch matrix if
desired. There is one Address0
register and one Address1
register per output channel. The
address register selects the input
to be connected to its output.
Connecting a particular input to a
particular output is done by
setting CH[6:0] to the desired
output channel. DATA[6:0] holds
the channel number of the
desired input channel. Table 3
summarizes the behavior of the
USE and SET bits. See Figure 4
for the timing diagram for SET,
and Figure 5 for the timing
diagram for USE.
Table 3. USE/SET Truth Table
Use
Set
Address Register Use
0
0
Using Address0 Registers for switch control, Reading/Writing Address0 Registers
0
1
Using Address0 Registers for switch control, Reading/Writing Address1 Registers
1
0
Using Address1 Registers for switch control, Reading/Writing Address0 Registers
1
1
Using Address1 Registers for switch control, Reading/Writing Address1 Registers
5