PIN2UCF Flow | Xilinx 8.2i instruction

Chapter 11: PIN2UCF

The following figure shows the flow through PIN2UCF.

NCD

(Placed and Routed -- For FPGAs)

GYD

(Pin Freeze File -- for CPLDs)

PIN2UCF

Report File

UCF File

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Figure 11-1: PIN2UCF Flow

The PIN2UCF program is used to back-annotate pin-locking constraints to the UCF from a successfully placed and routed design for an FPGA or a successfully fitted design for a CPLD.

PIN2UCF extracts pin locations and logical pad names from an existing NCD or GYD file and writes this information to a UCF. Pin-locking constraints are written to a PINLOCK section in the UCF. The PINLOCK section begins with the statement #PINLOCK BEGIN and ends with the statement #PINLOCK END. By default, PIN2UCF does not write conflicting constraints to a UCF. Prior to creating a PINLOCK section, if PIN2UCF discovers conflicting constraints, it writes information to a report file named pinlock.rpt.

The pinlock.rpt file has the following sections:

•Constraints Conflicts Information

This section has the following subsections. If there are no conflicting constraints, both subsections contain a single line indicating that there are no conflicts.

♦Net name conflicts on the pins

♦Pin name conflicts on the nets

Note: This section does not appear if there are fatal input errors, for example, missing inputs or invalid inputs.

•List of Errors and Warnings

This section appears only if there are errors or warnings.

User-specified pin-locking constraints are never overwritten in a UCF. However, if the user-specified constraints are exact matches of PIN2UCF generated constraints, a pound sign (#) is added in front of all matching user-specified location constraint statements. The pound sign indicates that a statement is a comment. To restore the original UCF (the file without the PINLOCK section), remove the PINLOCK section and delete the pound sign from each of the user-specified statements.

Note: PIN2UCF does not check if existing constraints in the UCF are valid pin-locking constraints.

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Development System Reference Guide

8.2i specifications

Xilinx 8.2i is a significant version of the Xilinx ISE (Integrated Software Environment) that emerged in the early 2000s, marking an important milestone in the world of FPGA (Field-Programmable Gate Array) development. This version introduced a slew of advanced features, technologies, and characteristics that made it an indispensable tool for engineers and developers in designing, simulating, and implementing digital circuits.

One of the standout features of Xilinx 8.2i is its enhanced design entry capabilities. This version supports multiple design entry methods, including schematic entry, VHDL, and Verilog HDL, giving engineers the flexibility to choose their preferred approach. The integrated environment provides user-friendly graphical interfaces, making it accessible for both novice and experienced users.

Xilinx 8.2i's synthesis tools have been improved to enable more efficient design compilation and optimization. The new algorithms used in this version facilitate faster synthesis times while reducing power consumption and improving performance. Furthermore, it features support for advanced FPGA architectures, which allows for the implementation of more complex designs with greater efficiency.

The implementation tools in Xilinx 8.2i include advanced place and route capabilities, utilizing state-of-the-art algorithms for optimized resource usage. These tools enable designers to make better use of FPGA resources, ensuring that designs fit within the constraints of the target device while maximizing performance.

Another key characteristic of Xilinx 8.2i is its extensive support for various Xilinx devices such as the Spartan, Virtex, and CoolRunner series. This compatibility ensures that developers can leverage the powerful features of these FPGA families, including high-speed transceivers and DSP slices.

Xilinx 8.2i also places a strong emphasis on simulation and verification. The version integrates with various simulation tools, allowing for thorough testing of the designs before implementation. This reduces the risk of errors and ensures that the final product meets specifications.

In addition, this version includes support for design constraints, enabling engineers to specify timing, area, and other critical design parameters. By accommodating constraints, Xilinx 8.2i helps in achieving reliable and efficient designs tailored to project needs.

In summary, Xilinx 8.2i is a robust software development tool that enhances the design process for FPGAs. Its comprehensive features, including multiple design entry options, advanced synthesis and implementation tools, extensive device support, and strong simulation capabilities, make it a valuable resource for engineers and developers striving for innovation in digital design.

Xilinx 8.2i manual PIN2UCF Flow

Models: 8.2i