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-rw-r--r--trunk/src/emu/machine/cdp1852.c221
1 files changed, 221 insertions, 0 deletions
diff --git a/trunk/src/emu/machine/cdp1852.c b/trunk/src/emu/machine/cdp1852.c
new file mode 100644
index 00000000000..ea11fdb15e6
--- /dev/null
+++ b/trunk/src/emu/machine/cdp1852.c
@@ -0,0 +1,221 @@
+/**********************************************************************
+
+ RCA CDP1852 Byte-Wide Input/Output Port emulation
+
+ Copyright Nicola Salmoria and the MAME Team.
+ Visit http://mamedev.org for licensing and usage restrictions.
+
+**********************************************************************/
+
+#include "cdp1852.h"
+#include "machine/devhelpr.h"
+
+
+// device type definition
+const device_type CDP1852 = &device_creator<cdp1852_device>;
+
+
+//**************************************************************************
+// MACROS / CONSTANTS
+//**************************************************************************
+
+enum
+{
+ MODE_INPUT = 0,
+ MODE_OUTPUT
+};
+
+
+
+//**************************************************************************
+// INLINE HELPERS
+//**************************************************************************
+
+//-------------------------------------------------
+// get_mode -
+//-------------------------------------------------
+
+int cdp1852_device::get_mode()
+{
+ return m_in_mode_func();
+}
+
+
+//-------------------------------------------------
+// set_sr_line -
+//-------------------------------------------------
+
+void cdp1852_device::set_sr_line(int state)
+{
+ if (m_sr != state)
+ {
+ m_sr = state;
+
+ m_out_sr_func(m_sr);
+ }
+}
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// cdp1852_device - constructor
+//-------------------------------------------------
+
+cdp1852_device::cdp1852_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, CDP1852, "CDP1852", tag, owner, clock)
+{
+}
+
+
+//-------------------------------------------------
+// device_config_complete - perform any
+// operations now that the configuration is
+// complete
+//-------------------------------------------------
+
+void cdp1852_device::device_config_complete()
+{
+ // inherit a copy of the static data
+ const cdp1852_interface *intf = reinterpret_cast<const cdp1852_interface *>(static_config());
+ if (intf != NULL)
+ *static_cast<cdp1852_interface *>(this) = *intf;
+
+ // or initialize to defaults if none provided
+ else
+ {
+ memset(&m_in_mode_cb, 0, sizeof(m_in_mode_cb));
+ memset(&m_out_sr_cb, 0, sizeof(m_out_sr_cb));
+ memset(&m_in_data_cb, 0, sizeof(m_in_data_cb));
+ memset(&m_out_data_cb, 0, sizeof(m_out_data_cb));
+ }
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void cdp1852_device::device_start()
+{
+ // resolve callbacks
+ m_in_mode_func.resolve(m_in_mode_cb, *this);
+ m_out_sr_func.resolve(m_out_sr_cb, *this);
+ m_in_data_func.resolve(m_in_data_cb, *this);
+ m_out_data_func.resolve(m_out_data_cb, *this);
+
+ // allocate timers
+ if (clock() > 0)
+ {
+ m_scan_timer = timer_alloc();
+ m_scan_timer->adjust(attotime::zero, 0, attotime::from_hz(clock()));
+ }
+
+ // register for state saving
+ save_item(NAME(m_new_data));
+ save_item(NAME(m_data));
+ save_item(NAME(m_next_data));
+ save_item(NAME(m_sr));
+ save_item(NAME(m_next_sr));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void cdp1852_device::device_reset()
+{
+ // reset data register
+ m_data = 0;
+
+ if (get_mode() == MODE_INPUT)
+ {
+ // reset service request flip-flop
+ set_sr_line(1);
+ }
+ else
+ {
+ // output data
+ m_out_data_func(0, m_data);
+
+ // reset service request flip-flop
+ set_sr_line(0);
+ }
+}
+
+
+//-------------------------------------------------
+// device_timer - handler timer events
+//-------------------------------------------------
+
+void cdp1852_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+{
+ switch (get_mode())
+ {
+ case MODE_INPUT:
+ // input data into register
+ m_data = m_in_data_func(0);
+
+ // signal processor
+ set_sr_line(0);
+ break;
+
+ case MODE_OUTPUT:
+ if (m_new_data)
+ {
+ m_new_data = 0;
+
+ // latch data into register
+ m_data = m_next_data;
+
+ // output data
+ m_out_data_func(0, m_data);
+
+ // signal peripheral device
+ set_sr_line(1);
+
+ m_next_sr = 0;
+ }
+ else
+ {
+ set_sr_line(m_next_sr);
+ }
+ break;
+ }
+}
+
+
+//-------------------------------------------------
+// read - data read
+//-------------------------------------------------
+
+READ8_MEMBER( cdp1852_device::read )
+{
+ if ((get_mode() == MODE_INPUT) && (clock() == 0))
+ {
+ // input data into register
+ m_data = m_in_data_func(0);
+ }
+
+ set_sr_line(1);
+
+ return m_data;
+}
+
+
+//-------------------------------------------------
+// write - data write
+//-------------------------------------------------
+
+WRITE8_MEMBER( cdp1852_device::write )
+{
+ if (get_mode() == MODE_OUTPUT)
+ {
+ m_next_data = data;
+ m_new_data = 1;
+ }
+}