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-rw-r--r--src/devices/bus/s100/polyfdc.cpp59
1 files changed, 38 insertions, 21 deletions
diff --git a/src/devices/bus/s100/polyfdc.cpp b/src/devices/bus/s100/polyfdc.cpp
index ca5defd523c..7de523aa059 100644
--- a/src/devices/bus/s100/polyfdc.cpp
+++ b/src/devices/bus/s100/polyfdc.cpp
@@ -4,9 +4,9 @@
PolyMorphic Systems Disk Controller
- This board controls up to three Shugart SA-400 drives using only
- generic serial and parallel interface chips and TTL (and an onboard
- 4 MHz XTAL). No schematics for this board have been found.
+ This board controls up to three Shugart SA400 Minifloppy drives using
+ only generic serial and parallel interface chips and TTL (and an
+ onboard 4 MHz XTAL).
****************************************************************************/
@@ -39,8 +39,8 @@ private:
void pc_w(u8 data);
// object finders
- required_device<mc6852_device> m_ssda;
- required_device<i8255_device> m_ppi;
+ required_device<mc6852_device> m_usrt;
+ required_device<i8255_device> m_pio;
};
DEFINE_DEVICE_TYPE_PRIVATE(S100_POLY_FDC, device_s100_card_interface, poly_fdc_device, "polyfdc", "PolyMorphic Systems Disk Controller")
@@ -48,8 +48,8 @@ DEFINE_DEVICE_TYPE_PRIVATE(S100_POLY_FDC, device_s100_card_interface, poly_fdc_d
poly_fdc_device::poly_fdc_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
: device_t(mconfig, S100_POLY_FDC, tag, owner, clock)
, device_s100_card_interface(mconfig, *this)
- , m_ssda(*this, "ssda")
- , m_ppi(*this, "ppi")
+ , m_usrt(*this, "usrt")
+ , m_pio(*this, "pio")
{
}
@@ -59,12 +59,12 @@ void poly_fdc_device::device_start()
u8 poly_fdc_device::s100_sinp_r(offs_t offset)
{
- if ((offset & 0xf000) == 0x2000)
+ if ((offset & 0x00f0) == 0x0020)
{
if (BIT(offset, 11))
- return m_ppi->read(offset & 3);
+ return m_pio->read(offset & 3);
else
- return m_ssda->read(offset & 1);
+ return m_usrt->read(offset & 1);
}
return 0xff;
@@ -72,37 +72,54 @@ u8 poly_fdc_device::s100_sinp_r(offs_t offset)
void poly_fdc_device::s100_sout_w(offs_t offset, u8 data)
{
- if ((offset & 0xf000) == 0x2000)
+ if ((offset & 0x00f0) == 0x20)
{
if (BIT(offset, 11))
- m_ppi->write(offset & 3, data);
+ m_pio->write(offset & 3, data);
else
- m_ssda->write(offset & 1, data);
+ m_usrt->write(offset & 1, data);
}
}
void poly_fdc_device::pa_w(u8 data)
{
+ // PA0, PA1 are decoded onto drive select lines
+ // DS1- (pin 10) = ~(~PA1 & PA0)
+ // DS2- (pin 12) = ~(PA1 & ~PA0)
+ // DS3- (pin 14) = ~(PA1 & PA0)
}
u8 poly_fdc_device::pb_r()
{
- return 0xff;
+ // PB0 = SC0+ (from index/sector counting circuit)
+ // PB1 = SC1+
+ // PB2 = SC2+
+ // PB3 = SC3+
+ // PB4 = TR0+ (inverted from SA400 pin 26)
+ // PB5 = WPRT+ (inverted from SA400 pin 28)
+ // PB6 = PB7 = GND
+ return 0;
}
void poly_fdc_device::pc_w(u8 data)
{
- // Port B interrupt
+ // PC0 = INT+ (buffered onto VI5-)
+ // PC2 = SCTR-
+ // PC3 = MTRON+ (inverted onto SA400 pin 16)
+ // PC4 = WCMD+
+ // PC5 = RCMD+
+ // PC6 = DS+ (inverted onto SA400 pin 18)
+ // PC7 = STEP+ (inverted onto SA400 pin 20)
m_bus->vi5_w(BIT(data, 0) ? ASSERT_LINE : CLEAR_LINE);
}
void poly_fdc_device::device_add_mconfig(machine_config &config)
{
- MC6852(config, m_ssda, 4_MHz_XTAL / 4); // actual clock unknown
+ MC6852(config, m_usrt, 0); // E generated from PDBIN+ and PWR-
- I8255(config, m_ppi);
- m_ppi->out_pa_callback().set(FUNC(poly_fdc_device::pa_w));
- m_ppi->in_pb_callback().set(FUNC(poly_fdc_device::pb_r));
- m_ppi->out_pc_callback().set(FUNC(poly_fdc_device::pc_w));
- m_ppi->tri_pc_callback().set_constant(0xfe);
+ I8255(config, m_pio);
+ m_pio->out_pa_callback().set(FUNC(poly_fdc_device::pa_w));
+ m_pio->in_pb_callback().set(FUNC(poly_fdc_device::pb_r));
+ m_pio->out_pc_callback().set(FUNC(poly_fdc_device::pc_w));
+ m_pio->tri_pc_callback().set_constant(0xfe);
}