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-rw-r--r--src/devices/bus/a2bus/booti.cpp171
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diff --git a/src/devices/bus/a2bus/booti.cpp b/src/devices/bus/a2bus/booti.cpp
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+// license:BSD-3-Clause
+// copyright-holders:R. Belmont
+/*********************************************************************
+
+ booti.cpp
+
+ Implementation of the BOOTI card
+
+ The BOOTI is an Apple II interface to the CH376 USB module.
+ The CH376 is intended for use with small microcontrollers (or,
+ you know, the 6502) to give them access to FAT-formatted
+ flash drives. See ch376.cpp for details.
+
+ C0n0: read/write data to CH376
+ C0n1: read status/write command to CH376
+ C0n4: $C800 ROM bank (0-3)
+
+*********************************************************************/
+
+#include "emu.h"
+#include "booti.h"
+
+/***************************************************************************
+ PARAMETERS
+***************************************************************************/
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(A2BUS_BOOTI, a2bus_booti_device, "a2booti", "Booti Card")
+
+ROM_START( booti )
+ ROM_REGION(0x2000, "flash", 0)
+ ROM_LOAD( "bootifw09l.bin", 0x000000, 0x002000, CRC(be3f21ff) SHA1(f505ad4685cd44e4cce5b8d6d27b9c4fea159f11) )
+ROM_END
+
+/***************************************************************************
+ FUNCTION PROTOTYPES
+***************************************************************************/
+
+//-------------------------------------------------
+// device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void a2bus_booti_device::device_add_mconfig(machine_config &config)
+{
+ AT28C64B(config, "flash", 0);
+
+ CH376(config, "ch376");
+}
+
+//-------------------------------------------------
+// rom_region - device-specific ROM region
+//-------------------------------------------------
+
+const tiny_rom_entry *a2bus_booti_device::device_rom_region() const
+{
+ return ROM_NAME( booti );
+}
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+a2bus_booti_device::a2bus_booti_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
+ device_t(mconfig, type, tag, owner, clock),
+ device_a2bus_card_interface(mconfig, *this),
+ m_flash(*this, "flash"),
+ m_ch376(*this, "ch376"),
+ m_rombank(0)
+{
+}
+
+a2bus_booti_device::a2bus_booti_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
+ a2bus_booti_device(mconfig, A2BUS_BOOTI, tag, owner, clock)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void a2bus_booti_device::device_start()
+{
+ save_item(NAME(m_rombank));
+}
+
+void a2bus_booti_device::device_reset()
+{
+ m_rombank = 0;
+}
+
+
+/*-------------------------------------------------
+ read_c0nx - called for reads from this card's c0nx space
+-------------------------------------------------*/
+
+uint8_t a2bus_booti_device::read_c0nx(uint8_t offset)
+{
+ switch (offset)
+ {
+ case 0:
+ case 1:
+ return m_ch376->read(offset);
+
+ case 4:
+ return m_rombank / 0x800;
+ }
+ return 0xff;
+}
+
+
+/*-------------------------------------------------
+ write_c0nx - called for writes to this card's c0nx space
+-------------------------------------------------*/
+
+void a2bus_booti_device::write_c0nx(uint8_t offset, uint8_t data)
+{
+ switch (offset)
+ {
+ case 0:
+ case 1:
+ m_ch376->write(offset, data);
+ break;
+
+ case 4:
+ m_rombank = 0x800 * (data & 3);
+ break;
+
+ default:
+ printf("Write %02x to c0n%x (%s)\n", data, offset, machine().describe_context().c_str());
+ break;
+ }
+}
+
+/*-------------------------------------------------
+ read_cnxx - called for reads from this card's cnxx space
+-------------------------------------------------*/
+
+uint8_t a2bus_booti_device::read_cnxx(uint8_t offset)
+{
+ // slot image at 0
+ return m_flash->read(offset);
+}
+
+void a2bus_booti_device::write_cnxx(uint8_t offset, uint8_t data)
+{
+}
+
+/*-------------------------------------------------
+ read_c800 - called for reads from this card's c800 space
+-------------------------------------------------*/
+
+uint8_t a2bus_booti_device::read_c800(uint16_t offset)
+{
+ return m_flash->read(offset + m_rombank);
+}
+
+/*-------------------------------------------------
+ write_c800 - called for writes to this card's c800 space
+-------------------------------------------------*/
+void a2bus_booti_device::write_c800(uint16_t offset, uint8_t data)
+{
+ // the card appears not to pass writes to $CFFF to the EEPROM,
+ // otherwise there's a false read of the next opcode after a $CFFF write and we crash.
+ if (offset < 0x7ff)
+ {
+ m_flash->write(offset + m_rombank, data);
+ }
+}