R

BSDLAnno File Composition

Explanation:

The only modification that is made to single-ended pins is when the pin is configured as an input. In this case, the boundary scan logic is disconnected from the output driver and is unable to drive out on the pin. When a pin is configured as an output, the boundary scan input register remains connected to that pin. As a result, the boundary scan logic has the same capabilities as if the pin were configured as a bidirectional pin.

BSDL File Modifications for Differential Pins

If pin 57 is configured as a differential output, differential three-state output, or differential bidirectional pin, modify as follows:

"9 (BC_1, *, controlr, 1)," &

"10 (BC_1, PAD57, output3, X, 9, 1, Z)," &

"11 (BC_1, PAD57, input, X)," &

If pin 57 is configured as a p-side differential input pin, modify as follows:

"9 (BC_1, *, internal, 1)," &

"10 (BC_1, *, internal, X)," &

"11 (BC_1, PAD57, input, X)," &

If pin 57 is configured as an n-side differential pin (all types: input, output, 3-state output, and bidirectional), modify as follows:

"9 (BC_1, *, internal, 1)," &

"10 (BC_1, *, internal, X)," &

"11 (BC_1, *, internal, X)," &

Explanation:

All interactions with differential pin pairs are handled by the boundary scan cells connected to the P-side pin. To capture the value on a differential pair, scan the P-side input register. To drive a value on a differential pair, shift the value into the P-side output register. The values in the N-side scan registers have no effect on that pin.

Most boundary scan devices use only three boundary scan registers for each differential pair. Most devices do not offer direct boundary scan control over each individual pin, but rather over the two pin pair. This makes sense when you consider that the two pins are transmitting only one bit of information - hence only one input, output, and control register is needed. Confusion arises over how differential pins are handled in Xilinx devices, because there are three boundary scan cells for each pin, or six registers for the differential pair. The N-side registers remain in the boundary scan register but are not connected to the pin in any way, which is why the N-side registers are listed as internal registers in the post-configuration BSDL file. The behavior of the N-side pin is controlled by the P-side boundary scan registers. For example, when a value is placed in the P-side output scan register and the output is enabled, the inverse value is driven onto the N-side pin by the output driver. This is independent from the Boundary Scan logic.

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Xilinx 8.2i manual Explanation
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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.
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