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-rw-r--r--src/devices/bus/bbc/internal/werom.cpp260
1 files changed, 260 insertions, 0 deletions
diff --git a/src/devices/bus/bbc/internal/werom.cpp b/src/devices/bus/bbc/internal/werom.cpp
new file mode 100644
index 00000000000..bc38500dee8
--- /dev/null
+++ b/src/devices/bus/bbc/internal/werom.cpp
@@ -0,0 +1,260 @@
+// license:BSD-3-Clause
+// copyright-holders:Nigel Barnes
+/**********************************************************************
+
+ Watford Electronics 12 ROM Board
+ http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/WE_12ROMboard.html
+
+ Watford Electronics 13 ROM Board
+ http://chrisacorns.computinghistory.org.uk/8bit_Upgrades/WE_13ROMBoard.html
+
+**********************************************************************/
+
+
+#include "emu.h"
+#include "werom.h"
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+DEFINE_DEVICE_TYPE(BBC_WE12ROM, bbc_we12rom_device, "bbc_we12rom", "Watford Electronics 12 ROM Board");
+DEFINE_DEVICE_TYPE(BBC_WE13ROM, bbc_we13rom_device, "bbc_we13rom", "Watford Electronics 13 ROM Board");
+
+
+//-------------------------------------------------
+// INPUT_PORTS( werom )
+//-------------------------------------------------
+
+static INPUT_PORTS_START(werom)
+ PORT_START("wp")
+ PORT_CONFNAME(0x01, 0x00, "Write Protect Sideways RAM")
+ PORT_CONFSETTING(0x00, DEF_STR(No))
+ PORT_CONFSETTING(0x01, DEF_STR(Yes))
+INPUT_PORTS_END
+
+//-------------------------------------------------
+// input_ports - device-specific input ports
+//-------------------------------------------------
+
+ioport_constructor bbc_we12rom_device::device_input_ports() const
+{
+ return INPUT_PORTS_NAME(werom);
+}
+
+//-------------------------------------------------
+// device_add_mconfig - add device configuration
+//-------------------------------------------------
+
+void bbc_we12rom_device::device_add_mconfig(machine_config &config)
+{
+ /* 12 rom sockets, 16K static ram (battery backed) */
+ 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, "nvram").set_fixed_ram(true);
+ BBC_ROMSLOT16(config, m_rom[15], bbc_rom_devices, nullptr);
+}
+
+void bbc_we13rom_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, 16K static ram (battery backed) */
+ 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, "nvram").set_fixed_ram(true);
+}
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// bbc_werom_device - constructor
+//-------------------------------------------------
+
+bbc_werom_device::bbc_werom_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_bbc_internal_interface(mconfig, *this)
+ , m_rom(*this, "romslot%u", 0U)
+{
+}
+
+bbc_we12rom_device::bbc_we12rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : bbc_werom_device(mconfig, BBC_WE12ROM, tag, owner, clock)
+ , m_wp(*this, "wp")
+{
+}
+
+bbc_we13rom_device::bbc_we13rom_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+ : bbc_werom_device(mconfig, BBC_WE13ROM, tag, owner, clock)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void bbc_we12rom_device::device_start()
+{
+ /* move internal roms to board */
+ memmove(m_region_swr->base() + 0x2c000, m_region_swr->base(), 0xc000);
+ memmove(m_region_swr->base() + 0x3c000, m_region_swr->base() + 0xc000, 0x4000);
+ memset(m_region_swr->base(), 0xff, 0x10000);
+
+ /* register for save states */
+ save_item(NAME(m_romsel));
+}
+
+void bbc_we13rom_device::device_start()
+{
+ /* move internal roms to board */
+ memmove(m_region_swr->base() + 0x2c000, 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_we12rom_device::paged_r(offs_t offset)
+{
+ uint8_t data = 0xff;
+
+ switch (m_romsel)
+ {
+ case 0: case 1: case 2: 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_we12rom_device::paged_w(offs_t offset, uint8_t data)
+{
+ switch (m_romsel)
+ {
+ case 0: case 1: case 2: 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);
+ }
+ /* sideways ram (if not write protected) */
+ if (!m_wp->read())
+ {
+ m_rom[14]->write(offset, data);
+ }
+ break;
+ }
+}
+
+
+uint8_t bbc_we13rom_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_we13rom_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);
+ }
+ /* sideways ram */
+ m_rom[15]->write(offset, data);
+ break;
+ }
+}