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Diffstat (limited to 'src/devices/cpu/alto2/a2mouse.c')
-rw-r--r-- | src/devices/cpu/alto2/a2mouse.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/src/devices/cpu/alto2/a2mouse.c b/src/devices/cpu/alto2/a2mouse.c new file mode 100644 index 00000000000..0844d45de6d --- /dev/null +++ b/src/devices/cpu/alto2/a2mouse.c @@ -0,0 +1,271 @@ +// 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; +} |