17.01.2015 Views

Programmable Logic Design Quick Start Handbook

Programmable Logic Design Quick Start Handbook

Programmable Logic Design Quick Start Handbook

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

XILINX SOLUTIONS<br />

FIGURE 2-8:<br />

SPARTAN-IIE INPUT/OUTPUT BLOCK<br />

The Spartan-IIE IOB features inputs and outputs that support 19 I/O signalling<br />

standards, including LVDS, BLVDS, LVPECL, LVCMOS, HSTL, SSTL,<br />

and GTL.<br />

These high-speed inputs and outputs are capable of supporting various<br />

state-of-the-art memory and bus interfaces. Three IOB registers function either<br />

as edge-triggered D-type flip-flops or as level-sensitive latches. Each IOB has a<br />

CLK shared by the three registers and independent CE signals for each register.<br />

In addition to the CLK and CE control signals, the three registers share a<br />

set/reset. For each register, you can independently configure this signal as a<br />

synchronous set, a synchronous reset, an asynchronous preset, or an asynchronous<br />

clear.<br />

Xilinx • 35

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!