USR_ACCESSE2 - 2021.2 English

Vivado Design Suite 7 Series FPGA and Zynq-7000 SoC Libraries Guide (UG953)

Document ID
UG953
Release Date
2021-10-22
Version
2021.2 English

Primitive: Configuration Data Access

Introduction

The USR_ACCESSE2 design element enables access to the 32-bit AXSS register within the configuration logic. This enables FPGA logic to access static data that can be set from the bitstream. The USR_ACCESSE2 register AXSS can be used to provide a single 32-bit constant value to the FPGA logic. The register contents can be defined during bitstream generation, avoiding the need to re-compile the design as would be required if distributed RAM was used to hold the constant. A constant can be used to track the version of the design, or any other information you require.

Port Descriptions

Port Direction Width Function
CFGCLK Output 1 Configuration Clock output.
DATA<31:0> Output 32 Configuration Data reflecting the contents of the AXSS register.
DATAVALID Output 1 Active-High data valid output.

Design Entry Method

Instantiation Recommended
Inference No
IP Catalog No
Macro support No

VHDL Instantiation Template

Unless they already exist, copy the following two statements and paste them before the entity declaration.
Library UNISIM;
use UNISIM.vcomponents.all;

-- USR_ACCESSE2: Configuration Data Access
--               7 Series
-- Xilinx HDL Language Template, version 2021.2

USR_ACCESSE2_inst : USR_ACCESSE2
port map (
   CFGCLK => CFGCLK,       -- 1-bit output: Configuration Clock output
   DATA => DATA,           -- 32-bit output: Configuration Data output
   DATAVALID => DATAVALID  -- 1-bit output: Active high data valid output
);

-- End of USR_ACCESSE2_inst instantiation

Verilog Instantiation Template


// USR_ACCESSE2: Configuration Data Access
//               7 Series
// Xilinx HDL Language Template, version 2021.2

USR_ACCESSE2 USR_ACCESSE2_inst (
   .CFGCLK(CFGCLK),       // 1-bit output: Configuration Clock output
   .DATA(DATA),           // 32-bit output: Configuration Data output
   .DATAVALID(DATAVALID)  // 1-bit output: Active high data valid output
);

// End of USR_ACCESSE2_inst instantiation

Related Information

  • See the 7 Series FPGAs Configuration Guide (UG470).