UbixOS V2 2.0

pit.c
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1 /*-
2 * Copyright (c) 2002-2018 The UbixOS Project.
3 * All rights reserved.
4 *
5 * This was developed by Christopher W. Olsen for the UbixOS Project.
6 *
7 * Redistribution and use in source and binary forms, with or without modification, are permitted
8 * provided that the following conditions are met:
9 *
10 * 1) Redistributions of source code must retain the above copyright notice, this list of
11 * conditions, the following disclaimer and the list of authors.
12 * 2) Redistributions in binary form must reproduce the above copyright notice, this list of
13 * conditions, the following disclaimer and the list of authors in the documentation and/or
14 * other materials provided with the distribution.
15 * 3) Neither the name of the UbixOS Project nor the names of its contributors may be used to
16 * endorse or promote products derived from this software without specific prior written
17 * permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
22 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
24 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <isa/pit.h>
30 #include <sys/io.h>
31 #include <lib/kprintf.h>
32
33 /*****************************************************************************************
34
35 Function: int pitInit()
36
37 Description: This Function Will Initialize The Programmable Timer
38
39 Notes:
40
41 0040 r/w PIT counter 0, counter divisor (XT, AT, PS/2)
42 0041 r/w PIT counter 1, RAM refresh counter (XT, AT)
43 0042 r/w PIT counter 2, cassette & speaker (XT, AT, PS/2)
44 0043 r/w PIT mode port, control word register for counters 0-2
45
46 bit 7-6 = 00 counter 0 select
47 = 01 counter 1 select (not PS/2)
48 = 10 counter 2 select
49 bit 5-4 = 00 counter latch command
50 = 01 read/write counter bits 0-7 only
51 = 10 read/write counter bits 8-15 only
52 = 11 read/write counter bits 0-7 first, then 8-15
53 bit 3-1 = 000 mode 0 select
54 = 001 mode 1 select - programmable one shot
55 = x10 mode 2 select - rate generator
56 = x11 mode 3 select - square wave generator
57 = 100 mode 4 select - software triggered strobe
58 = 101 mode 5 select - hardware triggered strobe
59 bit 0 = 0 binary counter 16 bits
60 = 1 BCD counter
61
62 *****************************************************************************************/
63 int pit_init() {
64 outportByteP(0x43, 0x36);
65 outportByteP(0x40, ((1193180 / PIT_TIMER) & 0xFF));
66 outportByte(0x40, (((1193180 / PIT_TIMER) >> 8) & 0xFF));
67
68 /* Print out information on the PIT */
69 kprintf("pit0 - Port [0x%X], Timer Hz: [%iHz]\n", 0x43, PIT_TIMER);
70
71 /* Return so we know everything went well */
72 return (0x0);
73 }
74
75 /***
76 $Log: pit.c,v $
77 Revision 1.1.1.1 2006/06/01 12:46:12 reddawg
78 ubix2
79
80 Revision 1.2 2005/10/12 00:13:37 reddawg
81 Removed
82
83 Revision 1.1.1.1 2005/09/26 17:24:03 reddawg
84 no message
85
86 Revision 1.7 2004/07/16 04:06:32 reddawg
87 Tune ups this stuff should of been taken care of months ago
88
89 Revision 1.6 2004/07/16 01:08:58 reddawg
90 Whew we work once again
91
92 Revision 1.5 2004/07/09 13:29:15 reddawg
93 pit: pitInit to pit_init
94 Adjusted initialization routines
95
96 Revision 1.4 2004/05/21 12:48:22 reddawg
97 Cleaned up
98
99 Revision 1.3 2004/05/20 22:51:09 reddawg
100 Cleaned Up Warnings
101
102 Revision 1.2 2004/05/10 02:23:24 reddawg
103 Minor Changes To Source Code To Prepare It For Open Source Release
104
105 END
106 ***/
107
outportByteP
void outportByteP(unsigned int port, unsigned char value)
outputut one byte to specified port with a delay
Definition: io.c:87
outportByte
void outportByte(unsigned int, unsigned char)
outputut one byte to specified port
Definition: io.c:72
pit.h
PIT_TIMER
#define PIT_TIMER
Definition: pit.h:32
kprintf.h
io.h
kprintf
int kprintf(const char *,...)
Definition: kprintf.c:259
pit_init
int pit_init()
Definition: pit.c:62