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-rw-r--r--src/devices/bus/c64/ieee488.c249
1 files changed, 249 insertions, 0 deletions
diff --git a/src/devices/bus/c64/ieee488.c b/src/devices/bus/c64/ieee488.c
new file mode 100644
index 00000000000..4b41417b42d
--- /dev/null
+++ b/src/devices/bus/c64/ieee488.c
@@ -0,0 +1,249 @@
+// license:BSD-3-Clause
+// copyright-holders:Curt Coder
+/**********************************************************************
+
+ Commodore IEEE-488 cartridge emulation
+
+**********************************************************************/
+
+#include "ieee488.h"
+
+
+
+//**************************************************************************
+// MACROS/CONSTANTS
+//**************************************************************************
+
+#define MOS6525_TAG "u3"
+
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type C64_IEEE488 = &device_creator<c64_ieee488_device>;
+
+
+//-------------------------------------------------
+// tpi6525_interface tpi_intf
+//-------------------------------------------------
+
+READ8_MEMBER( c64_ieee488_device::tpi_pa_r )
+{
+ /*
+
+ bit description
+
+ PA0
+ PA1
+ PA2 REN
+ PA3 ATN
+ PA4 DAV
+ PA5 EOI
+ PA6 NDAC
+ PA7 NRFD
+
+ */
+
+ UINT8 data = 0;
+
+ data |= m_bus->ren_r() << 2;
+ data |= m_bus->atn_r() << 3;
+ data |= m_bus->dav_r() << 4;
+ data |= m_bus->eoi_r() << 5;
+ data |= m_bus->ndac_r() << 6;
+ data |= m_bus->nrfd_r() << 7;
+
+ return data;
+}
+
+WRITE8_MEMBER( c64_ieee488_device::tpi_pa_w )
+{
+ /*
+
+ bit description
+
+ PA0 U4 DC
+ PA1 U4/U5 TE
+ PA2 REN
+ PA3 ATN
+ PA4 DAV
+ PA5 EOI
+ PA6 NDAC
+ PA7 NRFD
+
+ */
+
+ m_bus->ren_w(BIT(data, 2));
+ m_bus->atn_w(BIT(data, 3));
+ m_bus->dav_w(BIT(data, 4));
+ m_bus->eoi_w(BIT(data, 5));
+ m_bus->ndac_w(BIT(data, 6));
+ m_bus->nrfd_w(BIT(data, 7));
+}
+
+READ8_MEMBER( c64_ieee488_device::tpi_pc_r )
+{
+ /*
+
+ bit description
+
+ PC0 IFC
+ PC1 SRQ
+ PC2
+ PC3
+ PC4
+ PC5
+ PC6
+ PC7 slot _EXROM
+
+ */
+
+ UINT8 data = 0;
+
+ data |= m_bus->ifc_r();
+ data |= m_bus->srq_r() << 1;
+
+ data |= m_exp->exrom_r(offset, 1, 1, 1, 0) << 7;
+
+ return data;
+}
+
+WRITE8_MEMBER( c64_ieee488_device::tpi_pc_w )
+{
+ /*
+
+ bit description
+
+ PC0 IFC
+ PC1 SRQ
+ PC2
+ PC3 C64 _EXROM
+ PC4 _ROML select
+ PC5
+ PC6
+ PC7
+
+ */
+
+ m_bus->ifc_w(BIT(data, 0));
+ m_bus->srq_w(BIT(data, 1));
+
+ m_exrom = !BIT(data, 3);
+
+ m_roml_sel = BIT(data, 4);
+}
+
+//-------------------------------------------------
+// MACHINE_CONFIG_FRAGMENT( c64_ieee488 )
+//-------------------------------------------------
+
+static MACHINE_CONFIG_FRAGMENT( c64_ieee488 )
+ MCFG_DEVICE_ADD(MOS6525_TAG, TPI6525, 0)
+ MCFG_TPI6525_IN_PA_CB(READ8(c64_ieee488_device, tpi_pa_r))
+ MCFG_TPI6525_OUT_PA_CB(WRITE8(c64_ieee488_device, tpi_pa_w))
+ MCFG_TPI6525_IN_PB_CB(DEVREAD8(IEEE488_TAG, ieee488_device, dio_r))
+ MCFG_TPI6525_OUT_PB_CB(DEVWRITE8(IEEE488_TAG, ieee488_device, dio_w))
+ MCFG_TPI6525_IN_PC_CB(READ8(c64_ieee488_device, tpi_pc_r))
+ MCFG_TPI6525_OUT_PC_CB(WRITE8(c64_ieee488_device, tpi_pc_w))
+
+ MCFG_CBM_IEEE488_ADD(NULL)
+ MCFG_C64_PASSTHRU_EXPANSION_SLOT_ADD()
+MACHINE_CONFIG_END
+
+
+//-------------------------------------------------
+// machine_config_additions - device-specific
+// machine configurations
+//-------------------------------------------------
+
+machine_config_constructor c64_ieee488_device::device_mconfig_additions() const
+{
+ return MACHINE_CONFIG_NAME( c64_ieee488 );
+}
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// c64_ieee488_device - constructor
+//-------------------------------------------------
+
+c64_ieee488_device::c64_ieee488_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, C64_IEEE488, "IEEE-488", tag, owner, clock, "c64_ieee488", __FILE__),
+ device_c64_expansion_card_interface(mconfig, *this),
+ m_tpi(*this, MOS6525_TAG),
+ m_bus(*this, IEEE488_TAG),
+ m_exp(*this, C64_EXPANSION_SLOT_TAG),
+ m_roml_sel(1)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void c64_ieee488_device::device_start()
+{
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void c64_ieee488_device::device_reset()
+{
+ m_exrom = 0;
+}
+
+
+//-------------------------------------------------
+// c64_cd_r - cartridge data read
+//-------------------------------------------------
+
+UINT8 c64_ieee488_device::c64_cd_r(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2)
+{
+ data = m_exp->cd_r(space, offset, data, sphi2, ba, roml, romh, io1, io2);
+
+ if (!roml && m_roml_sel)
+ {
+ data = m_roml[offset & 0xfff];
+ }
+ else if (!io2)
+ {
+ data = m_tpi->read(space, offset & 0x07);
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// c64_cd_w - cartridge data write
+//-------------------------------------------------
+
+void c64_ieee488_device::c64_cd_w(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2)
+{
+ if (!io2)
+ {
+ m_tpi->write(space, offset & 0x07, data);
+ }
+
+ m_exp->cd_w(space, offset, data, sphi2, ba, roml, romh, io1, io2);
+}
+
+
+//-------------------------------------------------
+// c64_game_r - GAME read
+//-------------------------------------------------
+
+int c64_ieee488_device::c64_game_r(offs_t offset, int sphi2, int ba, int rw)
+{
+ return m_exp->game_r(offset, sphi2, ba, rw, m_slot->hiram());
+}