vi_clock.v
1.54 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
/**************************************************************************
* *
* Copyright (C) 1994, Silicon Graphics, Inc. *
* *
* These coded instructions, statements, and computer programs contain *
* unpublished proprietary information of Silicon Graphics, Inc., and *
* are protected by Federal copyright law. They may not be disclosed *
* to third parties or copied or duplicated in any form, in whole or *
* in part, without the prior written consent of Silicon Graphics, Inc. *
* *
*************************************************************************/
// $Id: vi_clock.v,v 1.1 2002/03/28 00:26:14 berndt Exp $
////////////////////////////////////////////////////////////////////////
//
// Project Reality
//
// module: vi_clock
// description: Clock select for video interface.
// Selecting processor clock allows us to run rambus, cpu
// and rcp at 4/5 nominal speed, while still making pixels
// at normal video rates.
//
// designer: Phil Gossett
// date: 10/13/94
//
////////////////////////////////////////////////////////////////////////
module vi_clock (clk, vbus_clock_in, vbus_clock_enable, vbus_clock_out);
input clk;
input vbus_clock_in;
input vbus_clock_enable;
output vbus_clock_out;
assign vbus_clock_out = vbus_clock_enable ? clk : vbus_clock_in;
endmodule // vi_clock