Answers Database


XPLA1: Clock resources available


Record #7633

Product Family: Hardware

Product Line: R3000

Product Part: R3032

Problem Title:
XPLA1: Clock resources available


Problem Description:
Urgency: Standard

General Description: What are the clock resource capabilities of the
XPLA1 devices?


Solution 1:

There are two sub families under XPLA1. Original (non-enhanced)
and Enhanced Clock devices.

The original devices of the XPLA1 family had a limited amount of
clocking resources. The 32 macrocell parts had two global clocks,
and the 64 and 128 devices had 4 global clocks.

These global clocks are comprised of two types of clocks. CLK0 is
a synchronous clock, which means that the clock network must be
driven from an external source. CLK1, CLK2, and CLK3 are
asynchronous clocks which means that they may be driven from an
internal product term. If these internal product term clocks are used,
this requires the use of a macrocell to construct these clocks, and the
pin associated with the macrocell is driven by the output buffer.

The Enhanced Clock devices add two product term clocks to each
logic block. These pt clocks are sum term or product term expressions
only, and are local only to the logic block.




End of Record #7633 - Last Modified: 10/11/99 16:15

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