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-rw-r--r--src/devices/bus/bbc/internal/romex.cpp134
1 files changed, 134 insertions, 0 deletions
diff --git a/src/devices/bus/bbc/internal/romex.cpp b/src/devices/bus/bbc/internal/romex.cpp
new file mode 100644
index 00000000000..9d7932db81f
--- /dev/null
+++ b/src/devices/bus/bbc/internal/romex.cpp
@@ -0,0 +1,134 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/**********************************************************************
+
+ GCC (Cambridge) Romex 13
+
+ http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/GCC_Romex13.html
+
+**********************************************************************/
+
+
+#include "emu.h"
+#include "romex.h"
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(BBC_ROMEX13, bbc_romex13_device, "bbc_romex13", "GCC Romex13 ROM Expansion");
+
+
+//-------------------------------------------------
+// device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void bbc_romex13_device::device_add_mconfig(machine_config &config)
+{
+ /* TODO: romslot2 is unavailable when board is fitted, replaced by socket on board */
+ //config.device_remove(":romslot2");
+
+ /* 13 rom sockets */
+ BBC_ROMSLOT16(config, m_rom[2], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[4], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[5], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[6], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[7], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[8], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[9], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[10], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[11], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[12], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[13], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[14], bbc_rom_devices, nullptr);
+ BBC_ROMSLOT16(config, m_rom[15], bbc_rom_devices, nullptr);
+}
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// bbc_romex13_device - constructor
+//-------------------------------------------------
+
+bbc_romex13_device::bbc_romex13_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : device_t(mconfig, BBC_ROMEX13, tag, owner, clock)
+ , device_bbc_internal_interface(mconfig, *this)
+ , m_rom(*this, "romslot%u", 0U)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void bbc_romex13_device::device_start()
+{
+ /* move internal roms to board */
+ memmove(m_region_swr->base() + 0x30000, m_region_swr->base(), 0x10000);
+ memset(m_region_swr->base(), 0xff, 0x10000);
+
+ /* register for save states */
+ save_item(NAME(m_romsel));
+}
+
+
+//**************************************************************************
+// IMPLEMENTATION
+//**************************************************************************
+
+uint8_t bbc_romex13_device::paged_r(offs_t offset)
+{
+ uint8_t data = 0xff;
+
+ switch (m_romsel)
+ {
+ case 0: case 1: case 3:
+ /* motherboard rom sockets */
+ if (m_mb_rom[m_romsel] && m_mb_rom[m_romsel]->present())
+ {
+ data = m_mb_rom[m_romsel]->read(offset);
+ }
+ else
+ {
+ data = m_region_swr->base()[offset + (m_romsel << 14)];
+ }
+ break;
+ default:
+ /* expansion board sockets */
+ if (m_rom[m_romsel] && m_rom[m_romsel]->present())
+ {
+ data = m_rom[m_romsel]->read(offset);
+ }
+ else
+ {
+ data = m_region_swr->base()[offset + (m_romsel << 14)];
+ }
+ break;
+ }
+
+ return data;
+}
+
+void bbc_romex13_device::paged_w(offs_t offset, uint8_t data)
+{
+ switch (m_romsel)
+ {
+ case 0: case 1: case 3:
+ /* motherboard rom sockets */
+ if (m_mb_rom[m_romsel])
+ {
+ m_mb_rom[m_romsel]->write(offset, data);
+ }
+ break;
+ default:
+ /* expansion board sockets */
+ if (m_rom[m_romsel])
+ {
+ m_rom[m_romsel]->write(offset, data);
+ }
+ break;
+ }
+}