Data Sheet

ManualsBrandsDigilent ManualsFPGACmod A7-35T Breadboardable Artix-7 FPGA Module

1300 Henley Court

Pullman, WA 99163

509.334.6306

www.digilentinc.com

Cmod A7 Reference Manual

Revised June 24, 2016

This manual applies to the Cmod A7 Rev. B

DOC#: 502-328

Other product and company names mentioned may be trademarks of their respective owners.

Page 1 of 10

Overview

The Digilent Cmod A7 is a small, 48-pin DIP form factor board built around a Xilinx Artix-7 FPGA. The board also

includes a USB-JTAG programming circuit, USB-UART bridge, clock source, Pmod host connector, SRAM, Quad-SPI

Flash, and basic I/O devices. These components make it a formidable, albeit compact, platform for digital logic

circuits and MicroBlaze™ embedded soft-core processor designs alike. There are 44 Digital FPGA I/O signals and

two FPGA Analog inputs that are routed to 100-mil-spaced through-hole pins so that users can integrate

programmable logic design directly into a solderless breadboard circuit. At just 0.7” by 2.75”, it can also be loaded

in a standard socket and used in embedded systems.

The Cmod A7 can be purchased with either an Artix-15T or Artix-35T FPGA. These two Cmod A7 product variants

are referred to as the Cmod A7-15T and Cmod A7-35T, respectively. When Digilent documentation describes

functionality that is common to both of these variants, they are referred to collectively as the “Cmod A7”. When

describing something that is only common to a specific variant, the variant will be explicitly called out by its name.

The only difference between the Cmod A7-15T and Cmod A7-35T are the capabilities of the FPGA found on the

board. They compare as follows:

The Cmod A7.

 System Features

o 512KB SRAM with an 8-bit bus and 8ns

access times

o 4MB Quad-SPI Flash

o USB-JTAG Programming Circuitry

o Powered from USB or external 3.3-5.5V

supply connected to DIP pins

 System Connectivity

o USB-UART bridge

 Interaction and Sensory Devices

o 2 LEDs

o 1 RGB LED

o 2 Push Buttons

 Expansion Connectors

o 48-pin DIP connector with 44 Digital I/O

and 2 Analog inputs (0-3.3V)

o One Pmod connector with 8 Digital I/O

Summary of content (10 pages)

PAGE 1
300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com Cmod A7 Reference Manual Revised June 24, 2016 This manual applies to the Cmod A7 Rev. B Overview The Digilent Cmod A7 is a small, 48-pin DIP form factor board built around a Xilinx Artix-7 FPGA. The board also includes a USB-JTAG programming circuit, USB-UART bridge, clock source, Pmod host connector, SRAM, Quad-SPI Flash, and basic I/O devices.
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Cmod A7 Reference Manual Product Variant Cmod A7-15T Cmod A7-35T FPGA Part XC7A15T-1CPG236C XC7A35T-1CPG236C 1 MSPS On-chip ADC Yes Yes Programming options Quad-SPI Flash/JTAG Quad-SPI Flash/JTAG Look-up Tables (LUTs) 10,400 20,800 Flip-Flops 20,800 41,600 Block RAM 112.5 KB 225 KB Clock Management Tiles 5 5 The Cmod A7 is fully compatible with the high-performance Vivado® Design Suite.
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Cmod A7 Reference Manual Net name Upstream net name Power IC Type Power IC Label Min/Typ/Max Voltage Max. Current Major Devices and Connectors VCC1V0 VU Switching PS IC10 0.95V/1.00V/1.05V 1.2A FPGA Core and Block RAM VCC1V8 VU Switching PS IC10 1.71V/1.80V/1.89V 0.6A FPGA AUX and ADC, USB Core 0.6A SRAM, USB Controller, PMOD, LEDS, Buttons, FPGA USER I/O VCC3V3 Switching PS VU IC10 3.135V/3.30V/3.465V Table 1.1. Power Rail Characteristics. 1.
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Cmod A7 Reference Manual 2 FPGA Configuration After power-on, the Artix-7 FPGA must be configured (or programmed) before it can perform any functions. Users can configure the FPGA in one of two ways: 1. 2. A PC can use the Digilent USB-JTAG circuitry to program the FPGA any time the power is on. A file stored in the nonvolatile serial (Quad-SPI) flash device can be transferred to the FPGA using the SPI port. On power-up, the Cmod A7 is programmed by the Quad-SPI flash.
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Cmod A7 Reference Manual device, a bitstream file is transferred to the flash in a two-step process. First, the FPGA is programmed with a circuit that can program flash devices, and then data is transferred to the flash device via the FPGA circuit (this complexity is hidden from the user by the Xilinx tools). This is called indirect programming. After the flash device has been programmed, it can automatically configure the FPGA at a subsequent power-on event.
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Cmod A7 Reference Manual accessed after configuration (pin E19). This allows access to this pin without having to instantiate the special FPGA primitive called STARTUPE2. Xilinx's AXI Quad SPI core can be used to read/write the flash in a MicroBlaze design. Refer to Xilinx's product guide for this core to learn more about using it, or to Micron's datasheet for the flash device to learn how to implement a custom controller. Figure 4.1. Cmod A7 Quad-SPI Flash.
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Cmod A7 Reference Manual Figure 5.1. Cmod A7 Quad-SPI Flash. 6 Basic I/O The Cmod A7 includes a tri-color LED, two push buttons, and two individual LEDs. The push buttons are connected to the FPGA via series resistors to prevent damage from inadvertent short circuits (a short circuit could occur if an FPGA pin assigned to a push button was inadvertently defined as an output).
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Cmod A7 Reference Manual cycle of each color between 5-% and 0% causes the different colors to be illuminated at different intensities, allowing virtually any color to be displayed. 7 DIP Connector The Cmod A7 has a 48-pin DIP connector for connecting to breadboards and custom fixtures. The pins have 100mil spacing, and the entire module is 0.7 inches by 2.75 inches.
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Cmod A7 Reference Manual 7.1 DIP Digital I/O The pins connected directly to the FPGA can be used as general purpose inputs or outputs. There are no series resistors between the FPGA and the DIP pins, so care should be taken not to cause shorts or connect them to voltages greater than allowed by the FPGA. The absolute maximum voltages for these pins are outlined in Table 7.1.
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Cmod A7 Reference Manual 8 Pmod Connector Pmod connecters are 2x6, right-angle, 100-mil spaced female connectors that mate with standard 2x6 pin headers. Each 12-pin Pmod connector provides two 3.3V VCC signals (pins 6 and 12), two ground signals (pins 5 and 11), and eight logic signals, as shown in Fig. 8.1.