libsidplayfp  1.8.3
c64cia.h
1 /*
2  * This file is part of libsidplayfp, a SID player engine.
3  *
4  * Copyright 2011-2014 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 
41 class c64cia1: public MOS6526, public Bank
42 {
43 private:
44  c64env &m_env;
45  uint_least16_t last_ta;
46 
47 protected:
48  void interrupt(bool state)
49  {
50  m_env.interruptIRQ (state);
51  }
52 
53  void portB()
54  {
55  m_env.lightpen((prb | ~ddrb) & 0x10);
56  }
57 
58 public:
59  c64cia1(c64env *env) :
60  MOS6526(&(env->context ())),
61  m_env(*env) {}
62 
63  void poke(uint_least16_t address, uint8_t value)
64  {
65  write(endian_16lo8(address), value);
66 
67  // Save the value written to Timer A
68  if (address == 0xDC04 || address == 0xDC05)
69  {
70  if (timerA.getTimer() != 0)
71  last_ta = timerA.getTimer();
72  }
73  }
74 
75  uint8_t peek(uint_least16_t address)
76  {
77  return read(endian_16lo8(address));
78  }
79 
80  void reset()
81  {
82  last_ta = 0;
83  MOS6526::reset ();
84  }
85 
86  uint_least16_t getTimerA() const { return last_ta; }
87 };
88 
96 class c64cia2: public MOS6526, public Bank
97 {
98 private:
99  c64env &m_env;
100 
101 protected:
102  void interrupt(bool state)
103  {
104  if (state)
105  m_env.interruptNMI ();
106  }
107 
108 public:
109  c64cia2(c64env *env) :
110  MOS6526(&(env->context ())),
111  m_env(*env) {}
112 
113  void poke(uint_least16_t address, uint8_t value)
114  {
115  write(address, value);
116  }
117 
118  uint8_t peek(uint_least16_t address)
119  {
120  return read(address);
121  }
122 };
123 
124 #endif // C64CIA_H
void poke(uint_least16_t address, uint8_t value)
Definition: c64cia.h:113
uint8_t & ddrb
Ports.
Definition: mos6526.h:118
Definition: c64cia.h:41
Definition: mos6526.h:103
void interrupt(bool state)
Definition: c64cia.h:48
TimerA timerA
Timers A and B.
Definition: mos6526.h:123
uint8_t peek(uint_least16_t address)
Definition: c64cia.h:118
Definition: c64env.h:37
uint8_t read(uint_least8_t addr)
Definition: mos6526.cpp:154
void reset()
Definition: c64cia.h:80
Definition: Bank.h:32
uint_least16_t getTimer() const
Definition: timer.h:208
void poke(uint_least16_t address, uint8_t value)
Definition: c64cia.h:63
uint8_t & prb
Ports.
Definition: mos6526.h:118
void write(uint_least8_t addr, uint8_t data)
Definition: mos6526.cpp:216
virtual void reset()
Definition: mos6526.cpp:131
void interrupt(bool state)
Definition: c64cia.h:102
Definition: c64cia.h:96
uint8_t peek(uint_least16_t address)
Definition: c64cia.h:75