Digilent Arty S7 Referenzhandbuch - Seite 11

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Pin 9

Pin 10

Table 8.1. Arty S7 Pmod Pinout.

8.1 Standard Pmod

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.

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.

(https://reference.digilentinc.com/_media/arty/arty_shield_pins.png)

Pin Name

Shield Function

IO0-IO9, A

General purpose I/O

(IO42), A10-A11

pins

IO26-IO33

General purpose I/O

pins

IO34-IO41

General purpose I/O

pins

SCL

I2C Clock

Pmod JA

M18

N18

Figure 9.1. Shield connector pin diagram.

Arty S7 Connection

See Section titled "Shield Digital I/O"

Pmod JB

N15

P16

Pmod JC

Pmod JD

R13

T11

V14

U11

Shared

Connections

–

Pmod JD

Pmod JC

–