In this lecture, we are looking at the basic output elements and their configurations on the Basys 3 board. 1
board. 2
Probably the simplest way to show digital signals is using LEDs. The Basys 3 board contains 16 individual 3
user LEDs connected to FPGA pins through a set of resistors. 4
Any logical value generated inside the FPGA can be represented on these LEDs following simple design methodologies. 5
Basys 3 board has an Artix 7 (XC7A35T) FPGA with CPG236 packaging code and based on the pin 6
configuration shown in this figure; it has 238 pins under the chip. 7
Each pin has a name that is the concatenation of a letter and a number which defines its position in a 2D 8
coordinate system. 9
For example, the name of this pin is U16. 10
This figure shows the connections between the FPGA and the components on the Basys 3 board. It can 11
be found on the Board Reference Manual available on the manufacturer website. To connect to the website, 12
use the QR code on this slide. 13
This picture shows the pin-name on the FPGA connected to LEDs. 14
Our design in the FPGA should drive these pins with proper data to turn on/off the corresponding LEDs. 15
As can be seen, 16
LEDs are connected together in a common cathode configuration, and their anodes are derived by FPGA via 330-ohm 17
resistors, 18
so for turning on an LED a logic high voltage (or logic value 1) should be applied to the corresponding 19
FPGA pin. 20
In the next lecture, I will explain the basic concepts behind the LED controller design in HLS and I will clarify 21
that this design consists of two parts a functional block described in C C++ and the connections between 22
this block and the FPGAs pins. 23
Takeaway points from this lecture are: The name of FPGA I/O pins connected to the LEDs that 24
we will use later. To turn on an LED, 25
we apply the logic value 1 to the corresponding FPGA pin. 26
This is the quiz for this lecture 27
Find the pin location of the seventh LED on the Basys3 board that is denoted by LD06 in the following 28
picture.