// license:GPL-2.0+
// copyright-holders:Juergen Buchmueller
/******************************************************************************
kim1.cpp - KIM-1
LED: six 7-segment LEDs
left 4 digits (address)
right 2 digits (data)
Keyboard: 23 keys and SST switch
0-F 16 keys to enter data
AD address entry mode
DA data entry mode
+ increment address
PC recalls address stored in the Program Counter
RS system reset
GO execute program
ST program stop
SST single step slide switch
How to use cassette:
00F1 00 to clear decimal mode
17F5-17F6 start address low and high
17F7-17F8 end address low and high
17F9 2 digit program ID
1800 press GO to save tape
1873 press GO to load tape
NOTE: save end address is next address from program end
The cassette interface
======================
The KIM-1 stores data on cassette using 2 frequencies: ~3700Hz (high) and ~2400Hz
(low). A high tone is output for 9 cycles and a low tone for 6 cycles. A logic bit
is encoded using 3 sequences of high and low tones. It always starts with a high
tone and ends with a low tone. The middle tone is high for a logic 0 and low for
0 logic 1.
These high and low tone signals are fed to a circuit containing a LM565 PLL and
a 311 comparator. For a high tone a 1 is passed to DB7 of 6530-U2 for a low tone
a 0 is passed. The KIM-1 software measures the time it takes for the signal to
change from 1 to 0.
Keyboard and Display logic
==========================
PA0-PA6 of 6530-U2 are connected to the columns of the keyboard matrix. These
columns are also connected to segments A-G of the LEDs. PB1-PB3 of 6530-U2 are
connected to a 74145 BCD which connects outputs 0-2 to the rows of the keyboard
matrix. Outputs 4-9 of the 74145 are connected to LEDs U18-U23
When a key is pressed the corresponding input to PA0-PA6 is set low and the KIM-1
software reads this signal. The KIM-1 software sends an output signal to PA0-PA6
and the corresponding segments of an LED are illuminated.
TODO:
- LEDs should be dark at startup (RS key to activate)
- hook up Single Step dip switch
- slots for expansion & application ports
- add TTY support
******************************************************************************/
#include "emu.h"
#include "includes/kim1.h"
#include "kim1.lh"
//**************************************************************************
// ADDRESS MAPS
//**************************************************************************
void kim1_state::kim1_map(address_map &map)
{
map(0x0000, 0x03ff).mirror(0xe000).ram();
map(0x1700, 0x173f).mirror(0xe000).rw("miot_u3", FUNC(mos6530_device::read), FUNC(mos6530_device::write));
map(0x1740, 0x177f).mirror(0xe000).rw(m_riot2, FUNC(mos6530_device::read), FUNC(mos6530_device::write));
map(0x1780, 0x17bf).mirror(0xe000).ram();
map(0x17c0, 0x17ff).mirror(0xe000).ram();
map(0x1800, 0x1bff).mirror(0xe000).rom();
map(0x1c00, 0x1fff).mirror(0xe000).rom();
}
// RS and ST key input
INPUT_CHANGED_MEMBER(kim1_state::trigger_reset)
{
m_maincpu->set_input_line(INPUT_LINE_RESET, newval ? CLEAR_LINE : ASSERT_LINE);
}
INPUT_CHANGED_MEMBER(kim1_state::trigger_nmi)
{
m_maincpu->set_input_line(INPUT_LINE_NMI, newval ? CLEAR_LINE : ASSERT_LINE);
}
//**************************************************************************
// INPUT PORTS
//**************************************************************************
static INPUT_PORTS_START( kim1 )
PORT_START("ROW0")
PORT_BIT( 0x80, 0x00, IPT_UNUSED )
PORT_BIT( 0x40, 0x40, IPT_KEYBOARD ) PORT_NAME("0") PORT_CODE(KEYCODE_0) PORT_CHAR('0') PORT_CODE(KEYCODE_0_PAD)
PORT_BIT( 0x20, 0x20, IPT_KEYBOARD ) PORT_NAME("1") PORT_CODE(KEYCODE_1) PORT_CHAR('1') PORT_CODE(KEYCODE_1_PAD)
PORT_BIT( 0x10, 0x10, IPT_KEYBOARD ) PORT_NAME("2") PORT_CODE(KEYCODE_2) PORT_CHAR('2') PORT_CODE(KEYCODE_2_PAD)
PORT_BIT( 0x08, 0x08, IPT_KEYBOARD ) PORT_NAME("3") PORT_CODE(KEYCODE_3) PORT_CHAR('3') PORT_CODE(KEYCODE_3_PAD)
PORT_BIT( 0x04, 0x04, IPT_KEYBOARD ) PORT_NAME("4") PORT_CODE(KEYCODE_4) PORT_CHAR('4') PORT_CODE(KEYCODE_4_PAD)
PORT_BIT( 0x02, 0x02, IPT_KEYBOARD ) PORT_NAME("5") PORT_CODE(KEYCODE_5) PORT_CHAR('5') PORT_CODE(KEYCODE_5_PAD)
PORT_BIT( 0x01, 0x01, IPT_KEYBOARD ) PORT_NAME("6") PORT_CODE(KEYCODE_6) PORT_CHAR('6') PORT_CODE(KEYCODE_6_PAD)
PORT_START("ROW1")
PORT_BIT( 0x80, 0x00, IPT_UNUSED )
PORT_BIT( 0x40, 0x40, IPT_KEYBOARD ) PORT_NAME("7") PORT_CODE(KEYCODE_7) PORT_CHAR('7') PORT_CODE(KEYCODE_7_PAD)
PORT_BIT( 0x20, 0x20, IPT_KEYBOARD ) PORT_NAME("8") PORT_CODE(KEYCODE_8) PORT_CHAR('8') PORT_CODE(KEYCODE_8_PAD)
PORT_BIT( 0x10, 0x10, IPT_KEYBOARD ) PORT_NAME("9") PORT_CODE(KEYCODE_9) PORT_CHAR('9') PORT_CODE(KEYCODE_9_PAD)
PORT_BIT( 0x08, 0x08, IPT_KEYBOARD ) PORT_NAME("A") PORT_CODE(KEYCODE_A) PORT_CHAR('A')
PORT_BIT( 0x04, 0x04, IPT_KEYBOARD ) PORT_NAME("B") PORT_CODE(KEYCODE_B) PORT_CHAR('B')
PORT_BIT( 0x02, 0x02, IPT_KEYBOARD ) PORT_NAME("C") PORT_CODE(KEYCODE_C) PORT_CHAR('C')
PORT_BIT( 0x01, 0x01, IPT_KEYBOARD ) PORT_NAME("D") PORT_CODE(KEYCODE_D) PORT_CHAR('D')
PORT_START("ROW2")
PORT_BIT( 0x80, 0x00, IPT_UNUSED )
PORT_BIT( 0x40, 0x40, IPT_KEYBOARD ) PORT_NAME("E") PORT_CODE(KEYCODE_E) PORT_CHAR('E')
PORT_BIT( 0x20, 0x20, IPT_KEYBOARD ) PORT_NAME("F") PORT_CODE(KEYCODE_F) PORT_CHAR('F')
PORT_BIT( 0x10, 0x10, IPT_KEYBOARD ) PORT_NAME("AD") PORT_CODE(KEYCODE_MINUS) PORT_CHAR('-') PORT_CODE(KEYCODE_MINUS_PAD)
PORT_BIT( 0x08, 0x08, IPT_KEYBOARD ) PORT_NAME("DA") PORT_CODE(KEYCODE_EQUALS) PORT_CHAR('=')
PORT_BIT( 0x04, 0x04, IPT_KEYBOARD ) PORT_NAME("+") PORT_CODE(KEYCODE_UP) PORT_CHAR(' ') PORT_CODE(KEYCODE_PLUS_PAD)
PORT_BIT( 0x02, 0x02, IPT_KEYBOARD ) PORT_NAME("GO") PORT_CODE(KEYCODE_ENTER) PORT_CHAR(13) PORT_CODE(KEYCODE_ENTER_PAD)
PORT_BIT( 0x01, 0x01, IPT_KEYBOARD ) PORT_NAME("PC") PORT_CODE(KEYCODE_F6)
PORT_START("SPECIAL")
PORT_BIT( 0x80, 0x00, IPT_UNUSED )
PORT_BIT( 0x40, 0x40, IPT_KEYBOARD ) PORT_NAME("sw1: ST") PORT_CODE(KEYCODE_F7) PORT_CHANGED_MEMBER(DEVICE_SELF, kim1_state, trigger_nmi, nullptr)
PORT_BIT( 0x20, 0x20, IPT_KEYBOARD ) PORT_NAME("sw2: RS") PORT_CODE(KEYCODE_F3) PORT_CHANGED_MEMBER(DEVICE_SELF, kim1_state, trigger_reset, nullptr)
PORT_DIPNAME(0x10, 0x10, "sw3: SS") PORT_CODE(KEYCODE_NUMLOCK) PORT_TOGGLE
PORT_DIPSETTING( 0x00, "single step")
PORT_DIPSETTING( 0x10, "run")
PORT_BIT( 0x08, 0x00, IPT_UNUSED )
PORT_BIT( 0x04, 0x00, IPT_UNUSED )
PORT_BIT( 0x02, 0x00, IPT_UNUSED )
PORT_BIT( 0x01, 0x00, IPT_UNUSED )
INPUT_PORTS_END
// Read from keyboard
READ8_MEMBER( kim1_state::kim1_u2_read_a )
{
uint8_t data = 0xff;
offs_t const sel = ( m_u2_port_b >> 1 ) & 0x0f;
if ( 3U > sel )
data = m_row[sel]->read();
return data;
}
// Write to 7-Segment LEDs
WRITE8_MEMBER( kim1_state::kim1_u2_write_a )
{
uint8_t idx = ( m_u2_port_b >> 1 ) & 0x0f;
if ( idx >= 4 && idx < 10 )
{
if ( data & 0x80 )
{
m_digit[idx - 4] = data & 0x7f;
m_led_time[idx - 4] = 15;
}
}
}
// Load from cassette
READ8_MEMBER( kim1_state::kim1_u2_read_b )
{
if ( m_riot2->portb_out_get() & 0x20 )
return 0xFF;
return 0x7F | ( m_311_output ^ 0x80 );
}
// Save to cassette
WRITE8_MEMBER( kim1_state::kim1_u2_write_b )
{
m_u2_port_b = data;
if ( data & 0x20 )
/* cassette write/speaker update */
m_cass->output(( data & 0x80 ) ? -1.0 : 1.0 );
/* Set IRQ when bit 7 is cleared */
}
TIMER_DEVICE_CALLBACK_MEMBER(kim1_state::kim1_cassette_input)
{
double tap_val = m_cass->input();
if ( tap_val <= 0 )
{
if ( m_cassette_high_count )
{
m_311_output = ( m_cassette_high_count < 8 ) ? 0x80 : 0;
m_cassette_high_count = 0;
}
}
if ( tap_val > 0 )
m_cassette_high_count++;
}
// Blank LEDs during cassette operations
TIMER_DEVICE_CALLBACK_MEMBER(kim1_state::kim1_update_leds)
{
uint8_t i;
for ( i = 0; i < 6; i++ )
{
if ( m_led_time[i] )
m_led_time[i]--;
else
m_digit[i] = 0;
}
}
// Register for save states
void kim1_state::machine_start()
{
m_digit.resolve();
save_item(NAME(m_u2_port_b));
save_item(NAME(m_311_output));
save_item(NAME(m_cassette_high_count));
}
void kim1_state::machine_reset()
{
uint8_t i;
for ( i = 0; i < 6; i++ )
m_led_time[i] = 0;
m_311_output = 0;
m_cassette_high_count = 0;
}
//**************************************************************************
// MACHINE DRIVERS
//**************************************************************************
MACHINE_CONFIG_START(kim1_state::kim1)
// basic machine hardware
MCFG_CPU_ADD("maincpu", M6502, 1000000) /* 1 MHz */
MCFG_CPU_PROGRAM_MAP(kim1_map)
MCFG_QUANTUM_TIME(attotime::from_hz(60))
// video hardware
MCFG_DEFAULT_LAYOUT( layout_kim1 )
// devices
MCFG_DEVICE_ADD("miot_u2", MOS6530, 1000000)
MCFG_MOS6530_IN_PA_CB(READ8(kim1_state, kim1_u2_read_a))
MCFG_MOS6530_OUT_PA_CB(WRITE8(kim1_state, kim1_u2_write_a))
MCFG_MOS6530_IN_PB_CB(READ8(kim1_state, kim1_u2_read_b))
MCFG_MOS6530_OUT_PB_CB(WRITE8(kim1_state, kim1_u2_write_b))
MCFG_DEVICE_ADD("miot_u3", MOS6530, 1000000)
MCFG_CASSETTE_ADD( "cassette" )
MCFG_CASSETTE_FORMATS(kim1_cassette_formats)
MCFG_CASSETTE_DEFAULT_STATE(CASSETTE_STOPPED)
MCFG_CASSETTE_INTERFACE ("kim1_cass")
MCFG_TIMER_DRIVER_ADD_PERIODIC("led_timer", kim1_state, kim1_update_leds, attotime::from_hz(60))
MCFG_TIMER_DRIVER_ADD_PERIODIC("cassette_timer", kim1_state, kim1_cassette_input, attotime::from_hz(44100))
// software list
MCFG_SOFTWARE_LIST_ADD ("cass_list", "kim1_cass")
MACHINE_CONFIG_END
//**************************************************************************
// ROM DEFINITIONS
//**************************************************************************
ROM_START(kim1)
ROM_REGION(0x10000,"maincpu",0)
ROM_LOAD("6530-003.bin", 0x1800, 0x0400, CRC(a2a56502) SHA1(60b6e48f35fe4899e29166641bac3e81e3b9d220))
ROM_LOAD("6530-002.bin", 0x1c00, 0x0400, CRC(2b08e923) SHA1(054f7f6989af3a59462ffb0372b6f56f307b5362))
ROM_END
//**************************************************************************
// SYSTEM DRIVERS
//**************************************************************************
// YEAR NAME PARENT COMPAT MACHINE INPUT CLASS INIT COMPANY FULLNAME FLAGS
COMP( 1975, kim1, 0, 0, kim1, kim1, kim1_state, 0, "MOS Technologies", "KIM-1" , MACHINE_NO_SOUND_HW | MACHINE_SUPPORTS_SAVE)