Datasheet

Figure 7.1. Arty S7 GPIO.
The four individual high-efficiency LEDs are anode-connected to the FPGA via 330-ohm resistors,
so they will turn on when a logic high voltage is applied to their respective I/O pin. Additional LEDs
that are not user-accessible indicate power-on, FPGA programming status, and USB and Ethernet
port status.
7.1 Tri-Color LEDs
The Arty S7 board contains two tri-color LEDs. Each tri-color LED has three input signals that drive
the cathodes of three smaller internal LEDs: one red, one blue, and one green. Driving the signal
corresponding to one of these colors high will illuminate the internal LED. The input signals are
driven by the FPGA through a transistor, which inverts the signals. Therefore, to light up the tri-
color LED, the corresponding signals need to be driven high. The tri-color LED will emit a color
dependent on the combination of internal LEDs that are currently being illuminated. For example,
if the red and blue signals are driven high and green is driven low, the tri-color LED will emit a
purple color.
Note: Digilent strongly recommends the use of pulse-width modulation (PWM) when driving the tri-
color LEDs. Driving any of the inputs to a steady logic ‘1’ will result in the LED being illuminated at
an uncomfortably bright level. You can avoid this by ensuring that none of the tri-color signals are
driven with more than a 50% duty cycle. Using PWM also greatly expands the potential color
palette of the tri-color LED. Individually adjusting the duty cycle of each color between 50% and