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-rw-r--r--src/devices/cpu/alto2/a2mouse.cpp271
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diff --git a/src/devices/cpu/alto2/a2mouse.cpp b/src/devices/cpu/alto2/a2mouse.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Juergen Buchmueller
+/*****************************************************************************
+ *
+ * Xerox AltoII mouse interface
+ *
+ *****************************************************************************/
+#include "alto2cpu.h"
+#include "a2roms.h"
+
+#define MOUSE_DIRTY_HACK 0
+
+enum {
+ MX1 = (1<<0), //!< MX1 signal is bit 0 (latch bit 1)
+ LMX1 = (1<<1),
+ MX2 = (1<<2), //!< MX2 signal is bit 2 (latch bit 3)
+ LMX2 = (1<<3),
+ MY1 = (1<<4), //!< MY1 signal is bit 4 (latch bit 5)
+ LMY1 = (1<<5),
+ MY2 = (1<<6), //!< MY2 signal is bit 6 (latch bit 7)
+ LMY2 = (1<<7),
+ MACTIVE = (MX1|MX2|MY1|MY2), //!< mask for the active bits
+ MLATCH = (LMX1|LMX2|LMY1|LMY2) //!< mask for the latched bits
+};
+
+/**
+ * <PRE>
+ * The mouse inputs from the shutters are connected to a quad
+ * 2/3 input RS flip flop (SN74279).
+ *
+ * 74279
+ * +---+--+---+
+ * | +--+ |
+ * R1 -|1 16|- Vcc
+ * | |
+ * S1a -|2 15|- S4
+ * | |
+ * S1b -|3 14|- R4
+ * | |
+ * Q1 -|4 13|- Q4
+ * | |
+ * R2 -|5 12|- S3a
+ * | |
+ * S2 -|6 11|- S3b
+ * | |
+ * Q2 -|7 10|- R3
+ * | |
+ * GND -|8 9|- Q3
+ * | |
+ * +----------+
+ *
+ * The 'Y' Encoder signals are connected to IC1:
+ * shutter pin(s) R/S output
+ * ------------------------------------
+ * 0 2,3 S1a,b Q1 MX2 -> 1
+ * 1 1 R1 Q1 MX2 -> 0
+ * 2 5 R2 Q2 MX1 -> 0
+ * 3 6 S2 Q2 MX1 -> 1
+ *
+ * The 'X' Encoder signals are connected to IC2:
+ * shutter pin(s) R/S output
+ * ------------------------------------
+ * 0 2,3 S1a,b Q1 MY2 -> 1
+ * 1 1 R1 Q1 MY2 -> 0
+ * 2 5 R2 Q2 MY1 -> 0
+ * 3 6 S2 Q2 MY1 -> 1
+ *
+ *
+ * The pulse train generated by a left or up rotation is:
+ *
+ * +---+ +---+ +---+
+ * MX1/MY1 | | | | | |
+ * ---+ +---+ +---+ +---
+ *
+ * +---+ +---+ +---+ +-
+ * MX2/MY2 | | | | | | |
+ * -+ +---+ +---+ +---+
+ *
+ *
+ * The pulse train generated by a right or down rotation is:
+ *
+ * +---+ +---+ +---+ +-
+ * MX1/MY1 | | | | | | |
+ * -+ +---+ +---+ +---+
+ *
+ * +---+ +---+ +---+
+ * MX2/MY2 | | | | | |
+ * ---+ +---+ +---+ +---
+ *
+ * In order to simulate the shutter sequence for the mouse motions
+ * we have to generate a sequence of pulses on MX1/MX2 and MY1/MY2
+ * that have their phases shifted by 90 degree.
+ * </PRE>
+ */
+
+
+#define MOVEX(x) ((((x) < 0) ? MY2 : ((x) > 0) ? MY1 : 0))
+#define MOVEY(y) ((((y) < 0) ? MX2 : ((y) > 0) ? MX1 : 0))
+#define SIGN(a) ((a) < 0 ? -1 : (a) > 0 ? 1 : 0)
+
+/**
+ * @brief return the mouse motion flags
+ *
+ * Advance the mouse x and y coordinates to the dx and dy
+ * coordinates by either toggling MX2 or MX1 first for a
+ * y movement, or MY2 or MY1 for x movement.
+ * There are four read phases counted by m_mouse.phase
+ *
+ * @return lookup value from madr_a32
+ */
+UINT16 alto2_cpu_device::mouse_read()
+{
+ UINT16 data;
+
+ m_mouse.latch = (m_mouse.latch << 1) & MLATCH;
+ data = m_madr_a32[m_mouse.latch];
+
+ switch (m_mouse.phase) {
+ case 0:
+ m_mouse.latch |= MOVEX(m_mouse.dx - m_mouse.x);
+ m_mouse.latch |= MOVEY(m_mouse.dy - m_mouse.y);
+ break;
+ case 1:
+ m_mouse.latch |= MACTIVE;
+ m_mouse.x -= SIGN(m_mouse.x - m_mouse.dx);
+ m_mouse.y -= SIGN(m_mouse.y - m_mouse.dy);
+ break;
+ case 2:
+ m_mouse.latch ^= MOVEX(m_mouse.dx - m_mouse.x);
+ m_mouse.latch ^= MOVEY(m_mouse.dy - m_mouse.y);
+ break;
+ default:
+ m_mouse.latch &= ~MACTIVE;
+ m_mouse.x -= SIGN(m_mouse.x - m_mouse.dx);
+ m_mouse.y -= SIGN(m_mouse.y - m_mouse.dy);
+ }
+ m_mouse.phase = (m_mouse.phase + 1) % 4;
+ return data;
+}
+
+/**
+ * @brief register a mouse motion in x direction
+ * @param ioport_field reference to the field
+ * @param param pointer passed in PORT_CHANGED_MEMBER last parameter
+ * @param oldval the old ioport_value
+ * @param newval the new ioport_value
+ */
+INPUT_CHANGED_MEMBER( alto2_cpu_device::mouse_motion_x )
+{
+ // set new destination (absolute) mouse x coordinate
+ INT32 x = m_mouse.dx + newval - oldval;
+ x = x < 0 ? 0 : x > 605 ? 605 : x;
+ m_mouse.dx = x;
+#if MOUSE_DIRTY_HACK
+ /* XXX: dirty, dirty, hack */
+#if USE_HAMMING_CHECK
+ m_mem.ram[0424/2] = hamming_code(1, 0424 / 2, (m_mouse.dx << 16) | m_mouse.dy);
+#else
+ m_mem.ram[0424/2] = (m_mouse.dx << 16) | m_mouse.dy;
+#endif
+#endif
+}
+
+/**
+ * @brief register a mouse motion in y direction
+ * @param ioport_field reference to the field
+ * @param param pointer passed in PORT_CHANGED_MEMBER last parameter
+ * @param oldval the old ioport_value
+ * @param newval the new ioport_value
+ */
+INPUT_CHANGED_MEMBER( alto2_cpu_device::mouse_motion_y )
+{
+ // set new destination (absolute) mouse y coordinate
+ INT32 y = m_mouse.dy + newval - oldval;
+ y = y < 0 ? 0 : y > 807 ? 807 : y;
+ m_mouse.dy = y;
+#if MOUSE_DIRTY_HACK
+ /* XXX: dirty, dirty, hack */
+#if USE_HAMMING_CHECK
+ m_mem.ram[0424/2] = hamming_code(1, 0424 / 2, (m_mouse.dx << 16) | m_mouse.dy);
+#else
+ m_mem.ram[0424/2] = (m_mouse.dx << 16) | m_mouse.dy;
+#endif
+#endif
+}
+
+/**
+ * @brief register a mouse button change
+ *
+ * convert button bit to UTILIN[13-15]
+ *
+ * @param ioport_field reference to the field
+ * @param param pointer passed in PORT_CHANGED_MEMBER last parameter
+ * @param oldval the old ioport_value
+ * @param newval the new ioport_value
+ */
+INPUT_CHANGED_MEMBER( alto2_cpu_device::mouse_button_0 )
+{
+ X_WRBITS(m_hw.utilin,16,13,13,newval);
+}
+
+INPUT_CHANGED_MEMBER( alto2_cpu_device::mouse_button_1 )
+{
+ X_WRBITS(m_hw.utilin,16,14,14,newval);
+}
+
+INPUT_CHANGED_MEMBER( alto2_cpu_device::mouse_button_2 )
+{
+ X_WRBITS(m_hw.utilin,16,15,15,newval);
+}
+
+static const prom_load_t pl_madr_a32 =
+{
+ "madr.a32",
+ 0,
+ "a0e3b4a7",
+ "24e50afdeb637a6a8588f8d3a3493c9188b8da2c",
+ /* size */ 0400,
+ /* amap */ AMAP_DEFAULT,
+ /* axor */ 0,
+ /* dxor */ 017, // invert D0-D3
+ /* width */ 4,
+ /* shift */ 0,
+ /* dmap */ DMAP_REVERSE_0_3, // reverse D0-D3 to D3-D0
+ /* dand */ ZERO,
+ /* type */ sizeof(UINT8)
+};
+
+/**
+ * @brief initialize the mouse context to useful values
+ *
+ * From the Alto Hardware Manual:
+ * <PRE>
+ * The mouse is a hand-held pointing device which contains two encoders
+ * which digitize its position as it is rolled over a table-top. It also
+ * has three buttons which may be read as the three low order bits of
+ * memory location UTILIN (0177030), iin the manner of the keyboard.
+ * The bit/button correspondence in UTILIN are (depressed keys
+ * correspond to 0's in memory):
+ *
+ * UTILIN[13] TOP or LEFT button (RED)
+ * UTILIN[14] BOTTOM or RIGHT button (BLUE)
+ * UTILIN[15] MIDDLE button (YELLOW)
+ *
+ * The mouse coordinates are maintained by the MRT microcode in locations
+ * MOUSELOC(0424)=X and MOUSELOC+1(0425)=Y in page one of the Alto memory.
+ * These coordinates are relative, i.e., the hardware only increments and
+ * decrements them. The resolution of the mouse is approximately 100 points
+ * per inch.
+ * </PRE>
+ */
+void alto2_cpu_device::init_mouse()
+{
+ memset(&m_mouse, 0, sizeof(m_mouse));
+ m_madr_a32 = prom_load(machine(), &pl_madr_a32, memregion("madr_a32")->base());
+}
+
+void alto2_cpu_device::exit_mouse()
+{
+ // nothing to do yet
+}
+
+void alto2_cpu_device::reset_mouse()
+{
+ m_mouse.x = 0;
+ m_mouse.y = 0;
+ m_mouse.dx = 0;
+ m_mouse.dy = 0;
+ m_mouse.latch = 0;
+ m_mouse.phase = 0;
+}