1 // license:BSD-3-Clause
2 // copyright-holders:Curt Coder
3 /**********************************************************************
4
5 Dela 64KB EPROM cartridge emulation
6
7 **********************************************************************/
8
9 #include "emu.h"
10 #include "dela_ep64.h"
11
12
13
14 //**************************************************************************
15 // DEVICE DEFINITIONS
16 //**************************************************************************
17
18 DEFINE_DEVICE_TYPE(C64_DELA_EP64, c64_dela_ep64_cartridge_device, "c64_dela_ep64", "C64 Rex 64KB EPROM cartridge")
19
20
21 //-------------------------------------------------
22 // device_add_mconfig - add device configuration
23 //-------------------------------------------------
24
device_add_mconfig(machine_config & config)25 void c64_dela_ep64_cartridge_device::device_add_mconfig(machine_config &config)
26 {
27 GENERIC_SOCKET(config, m_eprom1, generic_linear_slot, nullptr, "rom,bin");
28 GENERIC_SOCKET(config, m_eprom2, generic_linear_slot, nullptr, "rom,bin");
29 }
30
31
32 //**************************************************************************
33 // LIVE DEVICE
34 //**************************************************************************
35
36 //-------------------------------------------------
37 // c64_dela_ep64_cartridge_device - constructor
38 //-------------------------------------------------
39
c64_dela_ep64_cartridge_device(const machine_config & mconfig,const char * tag,device_t * owner,uint32_t clock)40 c64_dela_ep64_cartridge_device::c64_dela_ep64_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
41 device_t(mconfig, C64_DELA_EP64, tag, owner, clock),
42 device_c64_expansion_card_interface(mconfig, *this),
43 m_eprom1(*this, "eprom1"),
44 m_eprom2(*this, "eprom2"), m_bank(0), m_reset(0), m_rom0_ce(0), m_rom1_ce(0), m_rom2_ce(0)
45 {
46 }
47
48
49 //-------------------------------------------------
50 // device_start - device-specific startup
51 //-------------------------------------------------
52
device_start()53 void c64_dela_ep64_cartridge_device::device_start()
54 {
55 // state saving
56 save_item(NAME(m_bank));
57 save_item(NAME(m_reset));
58 save_item(NAME(m_rom0_ce));
59 save_item(NAME(m_rom1_ce));
60 save_item(NAME(m_rom2_ce));
61 }
62
63
64 //-------------------------------------------------
65 // device_reset - device-specific reset
66 //-------------------------------------------------
67
device_reset()68 void c64_dela_ep64_cartridge_device::device_reset()
69 {
70 m_exrom = 0;
71
72 m_reset = 1;
73 }
74
75
76 //-------------------------------------------------
77 // c64_cd_r - cartridge data read
78 //-------------------------------------------------
79
c64_cd_r(offs_t offset,uint8_t data,int sphi2,int ba,int roml,int romh,int io1,int io2)80 uint8_t c64_dela_ep64_cartridge_device::c64_cd_r(offs_t offset, uint8_t data, int sphi2, int ba, int roml, int romh, int io1, int io2)
81 {
82 if (!roml)
83 {
84 if (m_reset)
85 {
86 data = m_roml[offset & 0x1fff];
87 }
88 else
89 {
90 offs_t addr = (m_bank << 13) | (offset & 0x1fff);
91
92 if (!m_rom0_ce) data |= m_roml[offset & 0x1fff];
93 if (!m_rom1_ce) data |= m_eprom1->read_rom(addr);
94 if (!m_rom2_ce) data |= m_eprom2->read_rom(addr);
95 }
96 }
97
98 return data;
99 }
100
101
102 //-------------------------------------------------
103 // c64_cd_w - cartridge data write
104 //-------------------------------------------------
105
c64_cd_w(offs_t offset,uint8_t data,int sphi2,int ba,int roml,int romh,int io1,int io2)106 void c64_dela_ep64_cartridge_device::c64_cd_w(offs_t offset, uint8_t data, int sphi2, int ba, int roml, int romh, int io1, int io2)
107 {
108 if (!io1)
109 {
110 /*
111
112 bit description
113
114 0 IC6 _CE
115 1 IC5 _CE
116 2
117 3 IC4 _CE
118 4 A13
119 5 A14
120 6
121 7 EXROM
122
123 */
124
125 m_reset = 0;
126
127 m_rom0_ce = BIT(data, 3);
128 m_rom1_ce = BIT(data, 1);
129 m_rom2_ce = BIT(data, 0);
130
131 m_bank = (data >> 4) & 0x03;
132
133 m_exrom = BIT(data, 7);
134 }
135 }
136