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diff --git a/trunk/src/emu/machine/i8255.h b/trunk/src/emu/machine/i8255.h
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+/**********************************************************************
+
+ Intel 8255(A) Programmable Peripheral Interface emulation
+
+ Copyright MESS Team.
+ Visit http://mamedev.org for licensing and usage restrictions.
+
+**********************************************************************
+ _____ _____
+ PA3 1 |* \_/ | 40 PA4
+ PA2 2 | | 39 PA5
+ PA1 3 | | 38 PA6
+ PA0 4 | | 37 PA7
+ _RD 5 | | 36 WR
+ _CS 6 | | 35 RESET
+ GND 7 | | 34 D0
+ A1 8 | | 33 D1
+ A0 9 | | 32 D2
+ PC7 10 | 8255 | 31 D3
+ PC6 11 | 8255A | 30 D4
+ PC5 12 | | 29 D5
+ PC4 13 | | 28 D6
+ PC0 14 | | 27 D7
+ PC1 15 | | 26 Vcc
+ PC2 16 | | 25 PB7
+ PC3 17 | | 24 PB6
+ PB0 18 | | 23 PB5
+ PB1 19 | | 22 PB4
+ PB2 20 |_____________| 21 PB3
+
+**********************************************************************/
+
+#pragma once
+
+#ifndef __I8255__
+#define __I8255__
+
+#include "emu.h"
+
+
+
+//**************************************************************************
+// INTERFACE CONFIGURATION MACROS
+//**************************************************************************
+
+#define MCFG_I8255_ADD(_tag, _intrf) \
+ MCFG_DEVICE_ADD(_tag, I8255, 0) \
+ MCFG_DEVICE_CONFIG(_intrf)
+
+
+#define MCFG_I8255A_ADD(_tag, _intrf) \
+ MCFG_DEVICE_ADD(_tag, I8255A, 0) \
+ MCFG_DEVICE_CONFIG(_intrf)
+
+
+#define I8255_INTERFACE(name) \
+ const i8255_interface (name) =
+
+
+#define I8255A_INTERFACE(name) \
+ const i8255_interface (name) =
+
+
+//**************************************************************************
+// TYPE DEFINITIONS
+//**************************************************************************
+
+// ======================> i8255_interface
+
+struct i8255_interface
+{
+ devcb_read8 m_in_pa_cb;
+ devcb_write8 m_out_pa_cb;
+ devcb_read8 m_in_pb_cb;
+ devcb_write8 m_out_pb_cb;
+ devcb_read8 m_in_pc_cb;
+ devcb_write8 m_out_pc_cb;
+};
+
+
+// ======================> i8255_device
+
+class i8255_device : public device_t,
+ public i8255_interface
+{
+public:
+ // construction/destruction
+ i8255_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock);
+
+ DECLARE_READ8_MEMBER( read );
+ DECLARE_WRITE8_MEMBER( write );
+
+ DECLARE_READ8_MEMBER( pa_r );
+ UINT8 pa_r();
+
+ DECLARE_READ8_MEMBER( pb_r );
+ UINT8 pb_r();
+
+ DECLARE_WRITE_LINE_MEMBER( pc2_w );
+ DECLARE_WRITE_LINE_MEMBER( pc4_w );
+ DECLARE_WRITE_LINE_MEMBER( pc6_w );
+
+protected:
+ // device-level overrides
+ virtual void device_config_complete();
+ virtual void device_start();
+ virtual void device_reset();
+
+private:
+ inline void check_interrupt(int port);
+ inline void set_ibf(int port, int state);
+ inline void set_obf(int port, int state);
+ inline void set_inte(int port, int state);
+ inline void set_inte1(int state);
+ inline void set_inte2(int state);
+ inline void set_intr(int port, int state);
+ inline int group_mode(int group);
+ inline int port_mode(int port);
+ inline int port_c_lower_mode();
+ inline int port_c_upper_mode();
+
+ UINT8 read_mode0(int port);
+ UINT8 read_mode1(int port);
+ UINT8 read_mode2();
+ UINT8 read_pc();
+ void write_mode0(int port, UINT8 data);
+ void write_mode1(int port, UINT8 data);
+ void write_mode2(UINT8 data);
+ void write_pc(UINT8 data);
+ void output_pc();
+ void set_mode(UINT8 data);
+ void set_pc_bit(int bit, int state);
+
+ devcb_resolved_read8 m_in_port_func[3];
+ devcb_resolved_write8 m_out_port_func[3];
+
+ UINT8 m_control; // mode control word
+ UINT8 m_output[3]; // output latch
+ UINT8 m_input[3]; // input latch
+
+ int m_ibf[2]; // input buffer full flag
+ int m_obf[2]; // output buffer full flag, negative logic
+ int m_inte[2]; // interrupt enable
+ int m_inte1; // interrupt enable
+ int m_inte2; // interrupt enable
+ int m_intr[2]; // interrupt
+};
+
+
+// device type definition
+extern const device_type I8255;
+extern const device_type I8255A;
+
+
+
+#endif