From 1359d642c9656987b6d988e8aafb628841fcc97f Mon Sep 17 00:00:00 2001 From: Curt Coder Date: Sun, 20 Oct 2013 17:49:46 +0000 Subject: (MESS) c64: Moved expansion and user ports under emu/bus. (nw) --- src/emu/bus/c64/vw64.c | 130 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) create mode 100644 src/emu/bus/c64/vw64.c (limited to 'src/emu/bus/c64/vw64.c') diff --git a/src/emu/bus/c64/vw64.c b/src/emu/bus/c64/vw64.c new file mode 100644 index 00000000000..c613c2908f9 --- /dev/null +++ b/src/emu/bus/c64/vw64.c @@ -0,0 +1,130 @@ +// license:BSD-3-Clause +// copyright-holders:Curt Coder +/********************************************************************** + + VizaWrite 64 cartridge emulation + + Copyright MESS Team. + Visit http://mamedev.org for licensing and usage restrictions. + +**********************************************************************/ + +/* + + PCB Layout + ---------- + + |===========================| + |=| LS10 LS122 C | + |=| R | + |=| | + |=| | + |=| ROM0 ROM2 ROM1 | + |=| | + |=| | + |=| | + |===========================| + + ROM0 - Mitsubishi M5L2764K 8Kx8 EPROM "U" + ROM1 - Mitsubishi M5L2764K 8Kx8 EPROM "3" + ROM2 - Mitsubishi M5L2764K 8Kx8 EPROM "2" (located on solder side) + R - 56K + C - 47uF + +*/ + +#include "vw64.h" + + + +//************************************************************************** +// MACROS/CONSTANTS +//************************************************************************** + +#define UNSCRAMBLE_ADDRESS(_offset) \ + BITSWAP16(_offset,15,14,13,12,6,2,8,10,11,9,7,5,4,3,1,0) + +#define UNSCRAMBLE_DATA(_data) \ + BITSWAP8(_data,7,6,0,5,1,4,2,3) + + +// 74LS122 tW=0.45*R*C = 1.1844s +#define TIMER_PERIOD 1184 + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type C64_VW64 = &device_creator; + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// c64_vizawrite_cartridge_device - constructor +//------------------------------------------------- + +c64_vizawrite_cartridge_device::c64_vizawrite_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, C64_VW64, "VizaWrite 64", tag, owner, clock, "c64_vizawrite", __FILE__), + device_c64_expansion_card_interface(mconfig, *this) +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void c64_vizawrite_cartridge_device::device_start() +{ + // allocate timer + m_game_timer = timer_alloc(); +} + + +//------------------------------------------------- +// device_reset - device-specific reset +//------------------------------------------------- + +void c64_vizawrite_cartridge_device::device_reset() +{ + m_game = 0; + + m_game_timer->adjust(attotime::from_msec(TIMER_PERIOD), 0); +} + + +//------------------------------------------------- +// device_timer - handler timer events +//------------------------------------------------- + +void c64_vizawrite_cartridge_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) +{ + m_game = 1; +} + + +//------------------------------------------------- +// c64_cd_r - cartridge data read +//------------------------------------------------- + +UINT8 c64_vizawrite_cartridge_device::c64_cd_r(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2) +{ + if (!roml) + { + offs_t addr = (m_game << 13) | (offset & 0x1fff); + data = UNSCRAMBLE_DATA(m_roml[UNSCRAMBLE_ADDRESS(addr)]); + } + else if (!romh) + { + offs_t addr = offset & 0x1fff; + data = UNSCRAMBLE_DATA(m_romh[UNSCRAMBLE_ADDRESS(addr)]); + } + + return data; +} -- cgit v1.2.3-70-g09d2