libsidplayfp  2.0.1
c64cia.h
1 /*
2  * This file is part of libsidplayfp, a SID player engine.
3  *
4  * Copyright 2011-2019 Leandro Nini <drfiemost@users.sourceforge.net>
5  * Copyright 2007-2010 Antti Lankila
6  * Copyright 2001 Simon White
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21  */
22 
23 #ifndef C64CIA_H
24 #define C64CIA_H
25 
26 // The CIA emulations are very generic and here we need to effectively
27 // wire them into the computer (like adding a chip to a PCB).
28 
29 #include "Banks/Bank.h"
30 #include "c64/c64env.h"
31 #include "sidendian.h"
32 #include "CIA/mos6526.h"
33 
34 #include "sidcxx11.h"
35 
36 namespace libsidplayfp
37 {
38 
46 class c64cia1 final : public MOS6526, public Bank
47 {
48 private:
49  c64env &m_env;
50  uint_least16_t last_ta;
51 
52 protected:
53  void interrupt(bool state) override
54  {
55  m_env.interruptIRQ(state);
56  }
57 
58  void portB() override
59  {
60  m_env.lightpen((prb | ~ddrb) & 0x10);
61  }
62 
63 public:
64  c64cia1(c64env &env) :
65  MOS6526(env.scheduler()),
66  m_env(env) {}
67 
68  void poke(uint_least16_t address, uint8_t value) override
69  {
70  write(endian_16lo8(address), value);
71 
72  // Save the value written to Timer A
73  if (address == 0xDC04 || address == 0xDC05)
74  {
75  if (timerA.getTimer() != 0)
76  last_ta = timerA.getTimer();
77  }
78  }
79 
80  uint8_t peek(uint_least16_t address) override
81  {
82  return read(endian_16lo8(address));
83  }
84 
85  void reset() override
86  {
87  last_ta = 0;
89  }
90 
91  uint_least16_t getTimerA() const { return last_ta; }
92 };
93 
101 class c64cia2 : public MOS6526, public Bank
102 {
103 private:
104  c64env &m_env;
105 
106 protected:
107  void interrupt(bool state) override
108  {
109  if (state)
110  m_env.interruptNMI();
111  }
112 
113 public:
114  c64cia2(c64env &env) :
115  MOS6526(env.scheduler()),
116  m_env(env) {}
117 
118  void poke(uint_least16_t address, uint8_t value) override
119  {
120  write(endian_16lo8(address), value);
121  }
122 
123  uint8_t peek(uint_least16_t address) override
124  {
125  return read(endian_16lo8(address));
126  }
127 };
128 
129 }
130 
131 #endif // C64CIA_H
Definition: mos6526.h:181
Definition: exsid-emu.cpp:29
virtual void reset()
Definition: mos6526.cpp:202
void interrupt(bool state) override
Definition: c64cia.h:53
uint_least16_t getTimer() const
Definition: timer.h:212
void interrupt(bool state) override
Definition: c64cia.h:107
uint8_t & prb
Ports.
Definition: mos6526.h:199
MOS6526(EventScheduler &scheduler)
Definition: mos6526.cpp:178
void reset() override
Definition: c64cia.h:85
TimerA timerA
Timers A and B.
Definition: mos6526.h:207
uint8_t peek(uint_least16_t address) override
Definition: c64cia.h:80
void poke(uint_least16_t address, uint8_t value) override
Definition: c64cia.h:68
Definition: c64cia.h:101
uint8_t read(uint_least8_t addr)
Definition: mos6526.cpp:221
uint8_t & ddrb
Ports.
Definition: mos6526.h:199
Definition: Bank.h:35
Definition: c64cia.h:46
Definition: c64env.h:40
void write(uint_least8_t addr, uint8_t data)
Definition: mos6526.cpp:276
void poke(uint_least16_t address, uint8_t value) override
Definition: c64cia.h:118
uint8_t peek(uint_least16_t address) override
Definition: c64cia.h:123