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-rw-r--r--src/mame/machine/bigevglf.cpp103
1 files changed, 103 insertions, 0 deletions
diff --git a/src/mame/machine/bigevglf.cpp b/src/mame/machine/bigevglf.cpp
new file mode 100644
index 00000000000..bca48fed8af
--- /dev/null
+++ b/src/mame/machine/bigevglf.cpp
@@ -0,0 +1,103 @@
+// license:???
+// copyright-holders:Jarek Burczynski, Tomasz Slanina
+/***************************************************************************
+
+ machine.c
+
+ Functions to emulate general aspects of the machine (RAM, ROM, interrupts,
+ I/O ports)
+
+***************************************************************************/
+
+#include "emu.h"
+#include "includes/bigevglf.h"
+
+
+READ8_MEMBER(bigevglf_state::bigevglf_68705_port_a_r)
+{
+ return (m_port_a_out & m_ddr_a) | (m_port_a_in & ~m_ddr_a);
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_port_a_w)
+{
+ m_port_a_out = data;
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_ddr_a_w)
+{
+ m_ddr_a = data;
+}
+
+READ8_MEMBER(bigevglf_state::bigevglf_68705_port_b_r)
+{
+ return (m_port_b_out & m_ddr_b) | (m_port_b_in & ~m_ddr_b);
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_port_b_w)
+{
+ if ((m_ddr_b & 0x02) && (~m_port_b_out & 0x02) && (data & 0x02)) /* positive going transition of the clock */
+ {
+ m_mcu->set_input_line(0, CLEAR_LINE);
+ m_main_sent = 0;
+
+ }
+ if ((m_ddr_b & 0x04) && (~m_port_b_out & 0x04) && (data & 0x04) ) /* positive going transition of the clock */
+ {
+ m_from_mcu = m_port_a_out;
+ m_mcu_sent = 0;
+ }
+
+ m_port_b_out = data;
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_ddr_b_w)
+{
+ m_ddr_b = data;
+}
+
+READ8_MEMBER(bigevglf_state::bigevglf_68705_port_c_r)
+{
+ m_port_c_in = 0;
+ if (m_main_sent)
+ m_port_c_in |= 0x01;
+ if (m_mcu_sent)
+ m_port_c_in |= 0x02;
+
+ return (m_port_c_out & m_ddr_c) | (m_port_c_in & ~m_ddr_c);
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_port_c_w)
+{
+ m_port_c_out = data;
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_68705_ddr_c_w)
+{
+ m_ddr_c = data;
+}
+
+WRITE8_MEMBER(bigevglf_state::bigevglf_mcu_w)
+{
+ m_port_a_in = data;
+ m_main_sent = 1;
+ m_mcu->set_input_line(0, ASSERT_LINE);
+}
+
+
+READ8_MEMBER(bigevglf_state::bigevglf_mcu_r)
+{
+ m_mcu_sent = 1;
+ return m_from_mcu;
+}
+
+READ8_MEMBER(bigevglf_state::bigevglf_mcu_status_r)
+{
+ int res = 0;
+
+ if (!m_main_sent)
+ res |= 0x08;
+ if (!m_mcu_sent)
+ res |= 0x10;
+
+ return res;
+}