Digital Signal Processing Reference
In-Depth Information
Connecting the Signal Lines
When you move the mouse cursor near a wire, the cursor changes into a
crosshair. Move to one end of a wire you need to add and push and hold down
the left mouse button. Hold down the left mouse button and drag the end of the
wire to the other point that you want to connect. Release the left button to
connect the wire. If you need to delete a wire, click on it - the wire should turn
blue when selected. Hit the delete key to remove it. You can also use the
Right
Click
Delete
function. Connect the other wires using the same process so
that the diagram looks something like Figure 1.12
Figure 1.12
Active low OR-gate schematic example with I/O pins connected.
Enter the PIN Names
Right click on the first
INPUT
symbol. It will be outlined in blue
and a menu will appear. Select
Properties
, type
PB1
for the pin name and
click
OK
. Name the other input pin
PB2
and the output pin for the
LED
in a
similar fashion.
Assign the PIN Numbers to Connect the Pushbuttons and the LED
Since the FPGA chip is already prewired to the pushbuttons and the LED on
the printed circuit board (PCB), you need to look up the correct pin numbers
and designate them in your design.
Table 1.2 Hardwired I/O connections on the various FPGA boards in the design example.
I/O Device
DE1 Pin
DE2 Pin
UP3 Pin
UP2 & 1 Pin
PB1
R21 (Key1)
N23 (Key1)
62 (SW7)
28 (FLEX PB1)
PB2
T22 (Key2)
P23 (Key2)
48 (SW4)
29 (FLEX PB2)
LED
R20(LEDR0)
AE23(LEDR0)
56 (D3)
14 (7Seg Dec. pt.)
The information in Table 1.2 is from the documentation on the pinouts for the
various FPGA board user's manuals. (Table 2.4 lists additional I/O pins) In the
