Datasheet

8.2 High-Speed Pmod
The High-speed Pmods use the standard Pmod connector, but have their data signals routed as
impedance matched differential pairs for maximum switching speeds. They have pads for loading
resistors for added protection, but the Arty S7 ships with these loaded as 0-Ohm shunts. With the
series resistors shunted, these Pmods offer no protection against short circuits, but allow for much
faster switching speeds. The signals are paired to the adjacent signals in the same row: pins 1 and
2, pins 3 and 4, pins 7 and 8, and pins 9 and 10.
Traces are routed 100 ohm (+/- 10%) differential.
These connectors should be used only when high speed differential signaling is required or the
other Pmods are all occupied. If used as single-ended, coupled pairs may have significant
crosstalk. In applications where this is a concern, the standard Pmod connector shall be used.
Another option would be to ground one of the signals (drive it low from the FPGA) and use its pair
for the signal-ended signal.
Since the High-Speed Pmods have 0-ohm shunts instead of protection resistors, the operator must
take precaution to ensure that they do not cause any shorts.
9 Arduino/chipKIT Shield Connector
The Arty S7 can be connected to standard Arduino and chipKIT shields to add extended
functionality. Special care was taken while designing the Arty S7 to make sure it is compatible with
the majority of Arduino and chipKIT shields on the market. The shield connector has 45 pins
connected to the FPGA for general purpose Digital I/O. Due to the flexibility of FPGAs, it is possible
to use these pins for just about anything including digital read/write, SPI connections, UART
connections, I2C connections, and PWM. Six of these pins (labeled AN0-AN5) can also be used
as single-ended analog inputs with an input range of 0V-3.3V, and another four (labeled AN6-9)
can be used as differential analog input pairs with an input range of 0V-1.0V.
Note: The Arty S7 is not compatible with shields that output 5V digital or analog signals.
Driving pins on the Arty S7 shield connector above 5V may cause damage to the FPGA.
Figure 9.1 diagrams the pins found on the shield connector of the Arty S7.