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-rw-r--r--src/mame/drivers/zapcomputer.c175
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diff --git a/src/mame/drivers/zapcomputer.c b/src/mame/drivers/zapcomputer.c
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+++ b/src/mame/drivers/zapcomputer.c
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+// license:GPL2+
+// copyright-holders:FelipeSanches
+/*
+ ZAP - Z80 Applications Processor
+
+ driver by: Felipe Correa da Silva Sanches <juca@members.fsf.org>
+
+ Based on the technical descriptions and
+ assembly listings of the book:
+
+ "Build Your Own Z80 Microcomputer"
+ by Steve Ciarcia (1981)
+ published by BYTE/McGRAW-HILL
+
+ Basic usage instructions:
+ SHIFT + 0: view and edit memory values
+ SHIFT + 1: view and edit register values
+ SHIFT + 2: execution mode
+
+ For more info, please check chapter 6 "Monitor software" in the book
+ and/or the assembly listings of the ZAP monitor software
+ avaliable at appendix D.
+
+ Currently missing features in this driver:
+ * hookup RS232 support
+ * maybe also support video terminal described in chapter 9
+*/
+
+
+#include "emu.h"
+#include "cpu/z80/z80.h"
+#include "zapcomputer.lh"
+
+class zapcomp_state : public driver_device
+{
+public:
+ zapcomp_state(const machine_config &mconfig, device_type type, const char *tag)
+ : driver_device(mconfig, type, tag)
+ , m_maincpu(*this, "maincpu")
+ { }
+
+ DECLARE_READ8_MEMBER(keyboard_r);
+ DECLARE_WRITE8_MEMBER(display_7seg_w);
+
+private:
+ UINT8 decode7seg(UINT8 data);
+ virtual void machine_start();
+ required_device<cpu_device> m_maincpu;
+};
+
+UINT8 zapcomp_state::decode7seg(UINT8 data)
+{
+ //These are bit patterns representing the conversion of 4bit values
+ //into the status of the segments of the 7 segment displays
+ //controlled by a 82S23 PROM
+
+ UINT8 patterns[16] = {
+ 0x77, 0x41, 0x6e, 0x6b,
+ 0x59, 0x3b, 0x3f, 0x61,
+ 0x7f, 0x79, 0x7d, 0x1f,
+ 0x36, 0x4f, 0x3e, 0x3c
+ };
+
+ // Bit order for the FAIRCHILD FND-70
+ // 7-SEGMENT LCD: . g f e d c b a
+ return BITSWAP8(patterns[data & 0x0F], 7, 3, 4, 2, 1, 0, 6, 5);
+}
+
+WRITE8_MEMBER( zapcomp_state::display_7seg_w )
+{
+ switch (offset){
+ case 0: //Port 0x05 : address HI
+ output_set_digit_value(0, decode7seg(data >> 4));
+ output_set_digit_value(1, decode7seg(data));
+ break;
+ case 1: //Port 0x06 : address LOW
+ output_set_digit_value(2, decode7seg(data >> 4));
+ output_set_digit_value(3, decode7seg(data));
+ break;
+ case 2: //Port 0x07 : data
+ output_set_digit_value(4, decode7seg(data >> 4));
+ output_set_digit_value(5, decode7seg(data));
+ break;
+ default:
+ break;
+ }
+}
+
+READ8_MEMBER( zapcomp_state::keyboard_r )
+{
+ UINT8 retval = 0x00;
+ UINT8 special = ioport("X1")->read();
+ UINT16 hex_keys = ioport("X0")->read();
+
+ if BIT(special, 2) /* "SHIFT" key is pressed */
+ retval |= 0x40; /* turn on the SHIFT bit but DO NOT turn on the strobe bit */
+
+ if BIT(special, 1) /* "NEXT" key is pressed */
+ retval |= 0xA0; /* turn on the strobe & NEXT bits */
+
+ if BIT(special, 0) /* "EXEC" key is pressed */
+ retval |= 0x90; /* turn on the strobe & EXEC bit */
+
+ for (int i=0; i<16; i++)
+ if (hex_keys & (1 << i))
+ retval |= (0x80 | i); /* provide the key index in bits 3-0
+ as well as turning on the strobe bit */
+
+ return retval;
+}
+
+static ADDRESS_MAP_START( zapcomp_mem, AS_PROGRAM, 8, zapcomp_state )
+ AM_RANGE(0x0000, 0x03ff) AM_ROM AM_REGION("roms", 0) /* system monitor */
+ AM_RANGE(0x0400, 0x07ff) AM_RAM /* mandatory 1 kilobyte bank #0 */
+ AM_RANGE(0x0800, 0x0bff) AM_RAM /* extra 1 kilobyte bank #1 (optional) */
+ AM_RANGE(0x0c00, 0x0fff) AM_RAM /* extra 1 kilobyte bank #2 (optional) */
+ AM_RANGE(0x1000, 0x13ff) AM_RAM /* extra 1 kilobyte bank #3 (optional) */
+ AM_RANGE(0x1400, 0x17ff) AM_RAM /* extra 1 kilobyte bank #4 (optional) */
+ AM_RANGE(0x1800, 0x1bff) AM_RAM /* extra 1 kilobyte bank #5 (optional) */
+ AM_RANGE(0x1c00, 0x1fff) AM_RAM /* extra 1 kilobyte bank #6 (optional) */
+ AM_RANGE(0x2000, 0x23ff) AM_RAM /* extra 1 kilobyte bank #7 (optional) */
+ADDRESS_MAP_END
+
+static ADDRESS_MAP_START( zapcomp_io, AS_IO, 8, zapcomp_state )
+ ADDRESS_MAP_GLOBAL_MASK(0xff)
+ AM_RANGE(0x00, 0x00) AM_READ(keyboard_r)
+ AM_RANGE(0x05, 0x07) AM_WRITE(display_7seg_w)
+ADDRESS_MAP_END
+
+static INPUT_PORTS_START( zapcomp )
+ PORT_START("X0")
+ PORT_BIT( 0x0001, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_0) PORT_CHAR('0')
+ PORT_BIT( 0x0002, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_1) PORT_CHAR('1')
+ PORT_BIT( 0x0004, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_2) PORT_CHAR('2')
+ PORT_BIT( 0x0008, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_3) PORT_CHAR('3')
+ PORT_BIT( 0x0010, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_4) PORT_CHAR('4')
+ PORT_BIT( 0x0020, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_5) PORT_CHAR('5')
+ PORT_BIT( 0x0040, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_6) PORT_CHAR('6')
+ PORT_BIT( 0x0080, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_7) PORT_CHAR('7')
+ PORT_BIT( 0x0100, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_8) PORT_CHAR('8')
+ PORT_BIT( 0x0200, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_9) PORT_CHAR('9')
+ PORT_BIT( 0x0400, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_A) PORT_CHAR('a')
+ PORT_BIT( 0x0800, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_B) PORT_CHAR('b')
+ PORT_BIT( 0x1000, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_C) PORT_CHAR('c')
+ PORT_BIT( 0x2000, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_D) PORT_CHAR('d')
+ PORT_BIT( 0x4000, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_E) PORT_CHAR('e')
+ PORT_BIT( 0x8000, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_F) PORT_CHAR('f')
+
+ PORT_START("X1")
+ PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_NAME("EXEC") PORT_CODE(KEYCODE_ENTER)
+ PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_NAME("NEXT") PORT_CODE(KEYCODE_RIGHT)
+ PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_NAME("SHIFT") PORT_CODE(KEYCODE_LSHIFT) PORT_CODE(KEYCODE_RSHIFT)
+INPUT_PORTS_END
+
+void zapcomp_state::machine_start()
+{
+}
+
+static MACHINE_CONFIG_START( zapcomp, zapcomp_state )
+ // basic machine hardware
+ MCFG_CPU_ADD("maincpu", Z80, XTAL_2MHz)
+ MCFG_CPU_PROGRAM_MAP(zapcomp_mem)
+ MCFG_CPU_IO_MAP(zapcomp_io)
+
+ /* video hardware */
+ MCFG_DEFAULT_LAYOUT(layout_zapcomputer)
+MACHINE_CONFIG_END
+
+ROM_START( zapcomp )
+ ROM_REGION( 0x10000, "roms", 0 )
+ ROM_LOAD("zap.rom", 0x0000, 0x0400, CRC(3f4416e9) SHA1(d6493707bfba1a1e1e551f8144194afa5bda3316) )
+ROM_END
+
+// YEAR NAME PARENT COMPAT MACHINE INPUT CLASS INIT COMPANY FULLNAME FLAGS
+COMP( 1981, zapcomp, 0, 0, zapcomp, zapcomp, driver_device, 0, "Steve Ciarcia / BYTE / McGRAW-HILL", "ZAP - Z80 Applications Processor", MACHINE_NO_SOUND_HW )