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