xref: /freebsd/sys/dev/ic/via6522reg.h (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*
2  * Copyright 2004 by Peter Grehan. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
20  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
21  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
22  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef _VIA6522REG_H_
31 #define _VIA6522REG_H_
32 
33 /* Registers */
34 #define REG_OIRB	0	/* Input/output register B */
35 #define REG_OIRA	1	/* Input/output register A */
36 #define REG_DDRB	2	/* Data direction register B */
37 #define REG_DDRA	3	/* Data direction register A */
38 #define REG_T1CL	4	/* T1 low-order latch/low-order counter */
39 #define REG_T1CH	5	/* T1 high-order counter */
40 #define REG_T1LL	6	/* T1 low-order latches */
41 #define REG_T1LH	7	/* T1 high-order latches */
42 #define REG_T2CL	8	/* T2 low-order latch/low-order counter */
43 #define REG_T2CH	9	/* T2 high-order counter */
44 #define REG_SR		10	/* Shift register */
45 #define REG_ACR		11	/* Auxiliary control register */
46 #define REG_PCR		12	/* Peripheral control register */
47 #define REG_IFR		13	/* Interrupt flag register */
48 #define REG_IER		14	/* Interrupt-enable register */
49 #define REG_OIRA_NH	15	/* Input/output register A: no handshake */
50 
51 
52 /* Auxiliary control register (11) */
53 #define ACR_SR_NONE	0x0	/* Disabled */
54 #define ACR_SR_DIR	0x4	/* Bit for shift-register direction 1=out */
55 #define ACR_SRI_T2	0x1	/* Shift in under control of T2 */
56 #define ACR_SRI_PHI2	0x2	/*   "    "   "     "      " PHI2 */
57 #define ACR_SRI_EXTCLK	0x3	/*   "    "   "     "      " external clk */
58 #define ACR_SRO		0x4	/* Shift out free running at T2 rate */
59 #define ACR_SRO_T2	0x5	/* Shift out under control of T2 */
60 #define ACR_SRO_PHI2	0x6	/*   "    "   "     "      "  PHI2 */
61 #define ACR_SRO_EXTCLK	0x7	/*   "    "   "     "      "  external clk */
62 
63 #define ACR_T1_SHIFT	5	/* bits 7-5 */
64 #define ACR_SR_SHIFT	2	/* bits 4-2 */
65 
66 
67 /* Peripheral control register (12) */
68 #define PCR_INTCNTL	0x01	/* interrupt active edge: +ve=1, -ve=0 */
69 
70 #define PCR_CNTL_MASK	0x3	/* 3 bits */
71 #define PCR_CNTL_NEDGE	0x0	/* Input - negative active edge */
72 #define PCR_CNTL_INEDGE 0x1	/* Interrupt - negative active edge */
73 #define PCR_CNTL_PEDGE	0x2	/* Input - positive active edge */
74 #define PCR_CNTL_IPEDGE 0x3	/* Interrupt - positive active edge */
75 #define PCR_CNTL_HSHAKE 0x4	/* Handshake output */
76 #define PCR_CNTL_PULSE	0x5	/* Pulse output */
77 #define PCR_CNTL_LOW	0x6	/* Low output */
78 #define PCR_CNTL_HIGH	0x7	/* High output */
79 
80 #define PCR_CB2_SHIFT	5	/* bits 7-5 */
81 #define PCR_CB1_SHIFT	4	/* bit 4 */
82 #define PCR_CA2_SHIFT	1	/* bits 3-1 */
83 #define PCR_CA1_SHIFT	0	/* bit 0 */
84 
85 /* Interrupt flag register (13) */
86 #define IFR_CA2		0x01
87 #define IFR_CA1		0x02
88 #define IFR_SR		0x04
89 #define IFR_CB2		0x08
90 #define IFR_CB1		0x10
91 #define IFR_T2		0x20
92 #define IFR_T1		0x40
93 #define IFR_IRQB       	0x80	/* status of IRQB output pin */
94 
95 /* Interrupt enable register (14) */
96 #define IER_CA2		IFR_CA2
97 #define IER_CA1		IFR_CA1
98 #define IER_SR		IFR_SR
99 #define IER_CB2		IFR_CB2
100 #define IER_CB1		IFR_CB1
101 #define IER_T2		IFR_T2
102 #define IER_T1		IFR_T1
103 #define IER_IRQB	IFR_IRQB
104 
105 #endif /* _VIA6522REG_H_ */
106