xref: /freebsd/sys/dev/ic/via6522reg.h (revision b356ddf07671c7e0c960231344da7bddf5df42c4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright 2004 by Peter Grehan. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
22  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _VIA6522REG_H_
33 #define _VIA6522REG_H_
34 
35 /* Registers */
36 #define REG_OIRB	0	/* Input/output register B */
37 #define REG_OIRA	1	/* Input/output register A */
38 #define REG_DDRB	2	/* Data direction register B */
39 #define REG_DDRA	3	/* Data direction register A */
40 #define REG_T1CL	4	/* T1 low-order latch/low-order counter */
41 #define REG_T1CH	5	/* T1 high-order counter */
42 #define REG_T1LL	6	/* T1 low-order latches */
43 #define REG_T1LH	7	/* T1 high-order latches */
44 #define REG_T2CL	8	/* T2 low-order latch/low-order counter */
45 #define REG_T2CH	9	/* T2 high-order counter */
46 #define REG_SR		10	/* Shift register */
47 #define REG_ACR		11	/* Auxiliary control register */
48 #define REG_PCR		12	/* Peripheral control register */
49 #define REG_IFR		13	/* Interrupt flag register */
50 #define REG_IER		14	/* Interrupt-enable register */
51 #define REG_OIRA_NH	15	/* Input/output register A: no handshake */
52 
53 
54 /* Auxiliary control register (11) */
55 #define ACR_SR_NONE	0x0	/* Disabled */
56 #define ACR_SR_DIR	0x4	/* Bit for shift-register direction 1=out */
57 #define ACR_SRI_T2	0x1	/* Shift in under control of T2 */
58 #define ACR_SRI_PHI2	0x2	/*   "    "   "     "      " PHI2 */
59 #define ACR_SRI_EXTCLK	0x3	/*   "    "   "     "      " external clk */
60 #define ACR_SRO		0x4	/* Shift out free running at T2 rate */
61 #define ACR_SRO_T2	0x5	/* Shift out under control of T2 */
62 #define ACR_SRO_PHI2	0x6	/*   "    "   "     "      "  PHI2 */
63 #define ACR_SRO_EXTCLK	0x7	/*   "    "   "     "      "  external clk */
64 
65 #define ACR_T1_SHIFT	5	/* bits 7-5 */
66 #define ACR_SR_SHIFT	2	/* bits 4-2 */
67 
68 
69 /* Peripheral control register (12) */
70 #define PCR_INTCNTL	0x01	/* interrupt active edge: +ve=1, -ve=0 */
71 
72 #define PCR_CNTL_MASK	0x3	/* 3 bits */
73 #define PCR_CNTL_NEDGE	0x0	/* Input - negative active edge */
74 #define PCR_CNTL_INEDGE 0x1	/* Interrupt - negative active edge */
75 #define PCR_CNTL_PEDGE	0x2	/* Input - positive active edge */
76 #define PCR_CNTL_IPEDGE 0x3	/* Interrupt - positive active edge */
77 #define PCR_CNTL_HSHAKE 0x4	/* Handshake output */
78 #define PCR_CNTL_PULSE	0x5	/* Pulse output */
79 #define PCR_CNTL_LOW	0x6	/* Low output */
80 #define PCR_CNTL_HIGH	0x7	/* High output */
81 
82 #define PCR_CB2_SHIFT	5	/* bits 7-5 */
83 #define PCR_CB1_SHIFT	4	/* bit 4 */
84 #define PCR_CA2_SHIFT	1	/* bits 3-1 */
85 #define PCR_CA1_SHIFT	0	/* bit 0 */
86 
87 /* Interrupt flag register (13) */
88 #define IFR_CA2		0x01
89 #define IFR_CA1		0x02
90 #define IFR_SR		0x04
91 #define IFR_CB2		0x08
92 #define IFR_CB1		0x10
93 #define IFR_T2		0x20
94 #define IFR_T1		0x40
95 #define IFR_IRQB       	0x80	/* status of IRQB output pin */
96 
97 /* Interrupt enable register (14) */
98 #define IER_CA2		IFR_CA2
99 #define IER_CA1		IFR_CA1
100 #define IER_SR		IFR_SR
101 #define IER_CB2		IFR_CB2
102 #define IER_CB1		IFR_CB1
103 #define IER_T2		IFR_T2
104 #define IER_T1		IFR_T1
105 #define IER_IRQB	IFR_IRQB
106 
107 #endif /* _VIA6522REG_H_ */
108