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Diffstat (limited to 'src/mess/drivers/d6800.c')
-rw-r--r--src/mess/drivers/d6800.c84
1 files changed, 42 insertions, 42 deletions
diff --git a/src/mess/drivers/d6800.c b/src/mess/drivers/d6800.c
index a7af7769d51..b65f537dd9e 100644
--- a/src/mess/drivers/d6800.c
+++ b/src/mess/drivers/d6800.c
@@ -52,11 +52,11 @@ class d6800_state : public driver_device
public:
d6800_state(const machine_config &mconfig, device_type type, const char *tag)
: driver_device(mconfig, type, tag),
- m_maincpu(*this, "maincpu"),
- m_cass(*this, CASSETTE_TAG),
- m_pia(*this, "pia"),
- m_dac(*this, "dac"),
- m_videoram(*this, "videoram") { }
+ m_maincpu(*this, "maincpu"),
+ m_cass(*this, CASSETTE_TAG),
+ m_pia(*this, "pia"),
+ m_dac(*this, "dac"),
+ m_videoram(*this, "videoram") { }
DECLARE_READ8_MEMBER( d6800_cassette_r );
DECLARE_WRITE8_MEMBER( d6800_cassette_w );
@@ -199,9 +199,9 @@ READ_LINE_MEMBER( d6800_state::d6800_rtc_pulse )
READ_LINE_MEMBER( d6800_state::d6800_keydown_r )
{
UINT8 data = ioport("X0")->read()
- & ioport("X1")->read()
- & ioport("X2")->read()
- & ioport("X3")->read();
+ & ioport("X1")->read()
+ & ioport("X2")->read()
+ & ioport("X3")->read();
m_kbd_s = (data == 15) ? 0 : 1;
@@ -221,11 +221,11 @@ WRITE_LINE_MEMBER( d6800_state::d6800_screen_w )
READ8_MEMBER( d6800_state::d6800_cassette_r )
{
/*
- Cassette circuit consists of a 741 op-amp, a 74121 oneshot, and a 74LS74.
- When a pulse arrives, the oneshot is set. After a preset time, it triggers
- and the 74LS74 compares this pulse to the output of the 741. Therefore it
- knows if the tone is 1200 or 2400 Hz. Input to PIA is bit 7.
- */
+ Cassette circuit consists of a 741 op-amp, a 74121 oneshot, and a 74LS74.
+ When a pulse arrives, the oneshot is set. After a preset time, it triggers
+ and the 74LS74 compares this pulse to the output of the 741. Therefore it
+ knows if the tone is 1200 or 2400 Hz. Input to PIA is bit 7.
+ */
return ((m_cass->input() > 0.03) ? 1 : 0) | m_portb;
}
@@ -233,10 +233,10 @@ READ8_MEMBER( d6800_state::d6800_cassette_r )
WRITE8_MEMBER( d6800_state::d6800_cassette_w )
{
/*
- Cassette circuit consists of a 566 and a transistor. The 556 runs at 2400
- or 1200 Hz depending on the state of the transistor. This is controlled by
- bit 0 of the PIA. Bit 6 drives the speaker.
- */
+ Cassette circuit consists of a 566 and a transistor. The 556 runs at 2400
+ or 1200 Hz depending on the state of the transistor. This is controlled by
+ bit 0 of the PIA. Bit 6 drives the speaker.
+ */
m_cass->output(BIT(data, 0) ? -1.0 : +1.0);
@@ -247,9 +247,9 @@ WRITE8_MEMBER( d6800_state::d6800_cassette_w )
READ8_MEMBER( d6800_state::d6800_keyboard_r )
{
/*
- This system reads the key matrix one way, then swaps the input and output
- lines around and reads it another way. This isolates the key that was pressed.
- */
+ This system reads the key matrix one way, then swaps the input and output
+ lines around and reads it another way. This isolates the key that was pressed.
+ */
m_kbd_s++;
@@ -266,35 +266,35 @@ WRITE8_MEMBER( d6800_state::d6800_keyboard_w )
{
/*
- bit description
+ bit description
- PA0 keyboard column 0
- PA1 keyboard column 1
- PA2 keyboard column 2
- PA3 keyboard column 3
- PA4 keyboard row 0
- PA5 keyboard row 1
- PA6 keyboard row 2
- PA7 keyboard row 3
+ PA0 keyboard column 0
+ PA1 keyboard column 1
+ PA2 keyboard column 2
+ PA3 keyboard column 3
+ PA4 keyboard row 0
+ PA5 keyboard row 1
+ PA6 keyboard row 2
+ PA7 keyboard row 3
- */
+ */
}
static const pia6821_interface d6800_mc6821_intf =
{
- DEVCB_DRIVER_MEMBER(d6800_state, d6800_keyboard_r), /* port A input */
- DEVCB_DRIVER_MEMBER(d6800_state, d6800_cassette_r), /* port B input */
- DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_keydown_r), /* CA1 input */
- DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_rtc_pulse), /* CB1 input */
- DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_fn_key_r), /* CA2 input */
- DEVCB_NULL, /* CB2 input */
- DEVCB_DRIVER_MEMBER(d6800_state, d6800_keyboard_w), /* port A output */
- DEVCB_DRIVER_MEMBER(d6800_state, d6800_cassette_w), /* port B output */
- DEVCB_NULL, /* CA2 output */
- DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_screen_w), /* CB2 output */
- DEVCB_CPU_INPUT_LINE("maincpu", M6800_IRQ_LINE), /* IRQA output */
- DEVCB_CPU_INPUT_LINE("maincpu", M6800_IRQ_LINE) /* IRQB output */
+ DEVCB_DRIVER_MEMBER(d6800_state, d6800_keyboard_r), /* port A input */
+ DEVCB_DRIVER_MEMBER(d6800_state, d6800_cassette_r), /* port B input */
+ DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_keydown_r), /* CA1 input */
+ DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_rtc_pulse), /* CB1 input */
+ DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_fn_key_r), /* CA2 input */
+ DEVCB_NULL, /* CB2 input */
+ DEVCB_DRIVER_MEMBER(d6800_state, d6800_keyboard_w), /* port A output */
+ DEVCB_DRIVER_MEMBER(d6800_state, d6800_cassette_w), /* port B output */
+ DEVCB_NULL, /* CA2 output */
+ DEVCB_DRIVER_LINE_MEMBER(d6800_state, d6800_screen_w), /* CB2 output */
+ DEVCB_CPU_INPUT_LINE("maincpu", M6800_IRQ_LINE), /* IRQA output */
+ DEVCB_CPU_INPUT_LINE("maincpu", M6800_IRQ_LINE) /* IRQB output */
};
/* Machine Initialization */