diff options
Diffstat (limited to 'src/devices/bus/vidbrain/timeshare.c')
-rw-r--r-- | src/devices/bus/vidbrain/timeshare.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/src/devices/bus/vidbrain/timeshare.c b/src/devices/bus/vidbrain/timeshare.c new file mode 100644 index 00000000000..196bf66db2e --- /dev/null +++ b/src/devices/bus/vidbrain/timeshare.c @@ -0,0 +1,75 @@ +// license:BSD-3-Clause +// copyright-holders:Curt Coder +/********************************************************************** + + VideoBrain Timeshare cartridge emulation + +**********************************************************************/ + +#include "timeshare.h" + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type VB_TIMESHARE = &device_creator<videobrain_timeshare_cartridge_device>; + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// videobrain_timeshare_cartridge_device - constructor +//------------------------------------------------- + +videobrain_timeshare_cartridge_device::videobrain_timeshare_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, VB_TIMESHARE, "VideoBrain Timeshare cartridge", tag, owner, clock, "vb_timeshare", __FILE__), + device_videobrain_expansion_card_interface(mconfig, *this) +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void videobrain_timeshare_cartridge_device::device_start() +{ +} + + +//------------------------------------------------- +// videobrain_bo_r - cartridge data read +//------------------------------------------------- + +UINT8 videobrain_timeshare_cartridge_device::videobrain_bo_r(address_space &space, offs_t offset, int cs1, int cs2) +{ + UINT8 data = 0; + + if (!cs1) + { + data = m_rom[offset & m_rom_mask]; + } + else if (!cs2) + { + data = m_ram[offset & m_ram_mask]; + } + return data; +} + + +//------------------------------------------------- +// videobrain_bo_w - cartridge data write +//------------------------------------------------- + +void videobrain_timeshare_cartridge_device::videobrain_bo_w(address_space &space, offs_t offset, UINT8 data, int cs1, int cs2) +{ + if (!cs2) + { + m_ram[offset & m_ram_mask] = data; + } +} |