megadrive_test2

view src/io.h @ 11:302bcd73edc4

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added 6button support
author John Tsiombikas <nuclear@member.fsf.org>
date Sat, 24 Jun 2017 03:47:37 +0300
parents ca7108a82867
children
line source
1 #ifndef MEGADRIVE_IO_H_
2 #define MEGADRIVE_IO_H_
3
4 #include <stdint.h>
5
6 #define IO_REG_VER *((volatile uint8_t*)0xa10001)
7 #define IO_REG_DATA1 *((volatile uint8_t*)0xa10003)
8 #define IO_REG_DATA2 *((volatile uint8_t*)0xa10005)
9 #define IO_REG_DATA3 *((volatile uint8_t*)0xa10007)
10 #define IO_REG_CTRL1 *((volatile uint8_t*)0xa10009)
11 #define IO_REG_CTRL2 *((volatile uint8_t*)0xa1000b)
12 #define IO_REG_CTRL3 *((volatile uint8_t*)0xa1000d)
13 #define IO_REG_TXDATA1 *((volatile uint8_t*)0xa1000f)
14 #define IO_REG_RXDATA1 *((volatile uint8_t*)0xa10011)
15 #define IO_REG_S_CTRL1 *((volatile uint8_t*)0xa10013)
16 #define IO_REG_TXDATA2 *((volatile uint8_t*)0xa10015)
17 #define IO_REG_RXDATA2 *((volatile uint8_t*)0xa10017)
18 #define IO_REG_S_CTRL2 *((volatile uint8_t*)0xa10013)
19 #define IO_REG_TXDATA3 *((volatile uint8_t*)0xa1001b)
20 #define IO_REG_RXDATA3 *((volatile uint8_t*)0xa1001d)
21 #define IO_REG_S_CTRL3 *((volatile uint8_t*)0xa1001f)
22 #define IO_REG_LOCK *((volatile uint8_t*)0xa14000)
23 #define IO_REG_TMSS *((volatile uint8_t*)0xa14101)
24
25 #define IO_REG_DATA(x) *((volatile uint8_t*)0xa10003 + ((x) << 1))
26 #define IO_REG_CTRL(x) *((volatile uint8_t*)0xa10009 + ((x) << 1))
27
28
29 enum {
30 IO_VER_VERSION_MASK = 0x0f,
31 IO_VER_EXP = 0x20,
32 IO_VER_PAL = 0x40,
33 IO_VER_NONJP = 0x80
34 };
35
36 enum {
37 IO_PAD_UP = 0x001,
38 IO_PAD_DOWN = 0x002,
39 IO_PAD_LEFT = 0x004,
40 IO_PAD_RIGHT = 0x008,
41 IO_PAD_B = 0x010,
42 IO_PAD_C = 0x020,
43 IO_PAD_A = 0x040,
44 IO_PAD_START = 0x080,
45
46 IO_PAD_Z = 0x100,
47 IO_PAD_Y = 0x200,
48 IO_PAD_X = 0x400
49 };
50 #define IO_PAD_LOW_MASK 0x3f
51 #define IO_PAD_HIGH_MASK (IO_PAD_A | IO_PAD_START)
52
53 static inline void io_setdir(int port, uint8_t dir)
54 {
55 IO_REG_CTRL(port) = dir;
56 }
57
58 static inline uint16_t io_readpad(int port)
59 {
60 uint16_t bnstate;
61
62 bnstate = ~(IO_REG_DATA(port) << 2) & IO_PAD_HIGH_MASK;
63
64 IO_REG_DATA(port) = 0x40; /* select mode 1 */
65 asm volatile("nop");
66 asm volatile("nop");
67 bnstate |= ~IO_REG_DATA(port) & IO_PAD_LOW_MASK;
68
69 IO_REG_DATA(port) = 0; /* select mode 0 */
70 return bnstate;
71 }
72
73 static inline uint16_t io_readpad6(int port)
74 {
75 uint16_t bnstate;
76
77 IO_REG_DATA(port) = 0x40; /* start with mode 1 */
78 asm volatile("nop");
79 asm volatile("nop");
80 bnstate = ~IO_REG_DATA(port) & IO_PAD_LOW_MASK;
81
82 IO_REG_DATA(port) = 0; /* select mode 0 */
83 asm volatile("nop");
84 asm volatile("nop");
85 bnstate |= ~(IO_REG_DATA(port) << 2) & IO_PAD_HIGH_MASK;
86
87 /* then introduce two more rising edges to trigger extended mode */
88 IO_REG_DATA(port) = 0x40;
89 asm volatile("nop");
90 asm volatile("nop");
91 IO_REG_DATA(port) = 0;
92 asm volatile("nop");
93 asm volatile("nop");
94 IO_REG_DATA(port) = 0x40;
95 asm volatile("nop");
96 asm volatile("nop");
97
98 bnstate |= (uint16_t)(~IO_REG_DATA(port) & 0x7) << 8;
99 IO_REG_DATA(port) = 0; /* return mode to 0 */
100 return bnstate;
101 }
102
103 void io_init(void);
104 /*uint16_t io_readpad(int port);*/
105
106 #endif /* MEGADRIVE_IO_H_ */