Data Sheet

3/15/2018 Arty S7 Reference Manual [Reference.Digilentinc]
https://reference.digilentinc.com/reference/programmable-logic/arty-s7/reference-manual 17/22
Pmod JA Pmod JB Pmod JC Pmod JD
Pin 8 M17 P15 P13 R11
Pin 9 M18 N15 R13 T11
Pin 10 N18 P16 V14 U11
Table 8.1. Arty S7 Pmod Pinout.
The standard Pmod connectors are connected to the FPGA via 200 Ohm series resistors. The series resistors prevent short circuits that can
occur if the user accidentally drives a signal that is supposed to be used as an input. The downside to this added protection is that these
resistors can limit the maximum switching speed of the data signals. If the Pmod being used does not require high-speed access, then the
standard Pmod connector should be used to help prevent damage to the devices.
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.
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.
8.1 Standard Pmod
8.2 High-Speed Pmod
9 Arduino/chipKIT Shield Connector