XESS XStend, Руководство пользователя

Страница: 6 / 34

Listing 2: Connections between the XStend LEDs and the XS95.
# LEFT LED DIGIT SEGMENT CONNECTIONS (ACTIVE-LOW)
NET LS_0
LOC=P1;
NET LS_1 LOC=P2;
NET LS_2 LOC=P3;
NET LS_3 LOC=P75;
NET LS_4 LOC=P79;
NET LS_5 LOC=P82;
NET LS_6 LOC=P83;
NET LDP_ LOC=P84;
#
# RIGHT LED DIGIT SEGMENT CONNECTIONS (ACTIVE-LOW)
NET RS_0
LOC=P58;
NET RS_1 LOC=P56;
NET RS_2 LOC=P54;
NET RS_3 LOC=P55;
NET RS_4 LOC=P53;
NET RS_5 LOC=P57;
NET RS_6 LOC=P61;
NET RDP_ LOC=P34;
#
# INDIVIDUAL LED CONNECTIONS (ACTIVE-LOW)
NET D_1
LOC=P44;
NET D_2 LOC=P43;
NET D_3 LOC=P41;
NET D_4 LOC=P40;
NET D_5 LOC=P39;
NET D_6 LOC=P37;
NET D_7 LOC=P36;
NET D_8 LOC=P35;
2.3 Switches
The XStend has a bank of eight DIP switches and two pushbuttons (labelled SPARE and
RESET) that are accessible from the XS Boards. (There is a third pushbutton labelled
PROGRAM which is used to initiate the programming of the XS40 Board. It is not intended to
be a general-purpose input.)
When closed, each DIP switch pulls the connected pin of the XS Board to ground. When the
DIP switch is open, the pin is pulled high through a 10K
W
resistor.
*
When not being used, the DIP switches should be left in the open configuration so the pins of
the XS Board are not tied to ground and can freely move between logic low and high levels.
When pressed, each pushbutton pulls the connected pin of the XS Board to ground. Otherwise,
the pin is pulled high through a 10 K
W
resistor.
Here are the connections from the XS40 and XS95 Boards to the switches on the XStend Board
expressed as UCF constraints (for the UCF syntax and usage tips, check out
http://www.xilinx.com/techdocs/2449.htm):