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Diffstat (limited to 'src/devices/machine/40105.cpp')
-rw-r--r-- | src/devices/machine/40105.cpp | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/src/devices/machine/40105.cpp b/src/devices/machine/40105.cpp new file mode 100644 index 00000000000..e2f059dfed0 --- /dev/null +++ b/src/devices/machine/40105.cpp @@ -0,0 +1,172 @@ +// license:BSD-3-Clause +// copyright-holders:Curt Coder +/********************************************************************** + + CMOS 40105 FIFO Register emulation + +**********************************************************************/ + +#include "40105.h" + + + +//************************************************************************** +// MACROS / CONSTANTS +//************************************************************************** + +#define LOG 0 + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type CMOS_40105 = &device_creator<cmos_40105_device>; + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// cmos_40105_device - constructor +//------------------------------------------------- + +cmos_40105_device::cmos_40105_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) + : device_t(mconfig, CMOS_40105, "40105", tag, owner, clock, "40105", __FILE__), + m_write_dir(*this), + m_write_dor(*this) +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void cmos_40105_device::device_start() +{ + // resolve callbacks + m_write_dir.resolve_safe(); + m_write_dor.resolve_safe(); + + // state saving + save_item(NAME(m_d)); + save_item(NAME(m_q)); + save_item(NAME(m_dir)); + save_item(NAME(m_dor)); + save_item(NAME(m_si)); + save_item(NAME(m_so)); +} + + +//------------------------------------------------- +// device_reset - device-specific reset +//------------------------------------------------- + +void cmos_40105_device::device_reset() +{ + m_fifo = std::queue<UINT8>(); + + m_dir = 1; + m_dor = 0; + m_si = 0; + + m_write_dir(m_dir); + m_write_dor(m_dor); +} + + +//------------------------------------------------- +// read - read Q +//------------------------------------------------- + +UINT8 cmos_40105_device::read() +{ + return m_q; +} + + +//------------------------------------------------- +// write - write D +//------------------------------------------------- + +void cmos_40105_device::write(UINT8 data) +{ + m_d = data & 0x0f; +} + + +//------------------------------------------------- +// si_w - shift in write +//------------------------------------------------- + +WRITE_LINE_MEMBER( cmos_40105_device::si_w ) +{ + if (m_dir && !m_si && state) + { + m_fifo.push(m_d); + + if (m_fifo.size() == 16) + { + m_dir = 0; + m_write_dir(m_dir); + } + + if (!m_dor) + { + m_dor = 1; + m_write_dor(m_dor); + } + + } + + m_si = state; +} + + +//------------------------------------------------- +// so_w - shift out write +//------------------------------------------------- + +WRITE_LINE_MEMBER( cmos_40105_device::so_w ) +{ + if (m_dor && m_so && !m_so) + { + m_dor = 0; + m_write_dor(m_dor); + + m_q = m_fifo.front(); + m_fifo.pop(); + + if (m_fifo.size() > 0) + { + m_dor = 1; + m_write_dor(m_dor); + } + } + + m_so = state; +} + + +//------------------------------------------------- +// dir_r - data in ready read +//------------------------------------------------- + +READ_LINE_MEMBER( cmos_40105_device::dir_r ) +{ + return m_dir; +} + + +//------------------------------------------------- +// dor_r - data out ready read +//------------------------------------------------- + +READ_LINE_MEMBER( cmos_40105_device::dor_r ) +{ + return m_dor; +} |