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Diffstat (limited to 'src/devices/cpu/pps41/mm78laop.cpp')
-rw-r--r--src/devices/cpu/pps41/mm78laop.cpp73
1 files changed, 73 insertions, 0 deletions
diff --git a/src/devices/cpu/pps41/mm78laop.cpp b/src/devices/cpu/pps41/mm78laop.cpp
new file mode 100644
index 00000000000..88b59a12e0c
--- /dev/null
+++ b/src/devices/cpu/pps41/mm78laop.cpp
@@ -0,0 +1,73 @@
+// license:BSD-3-Clause
+// copyright-holders:hap
+
+// MM77LA/MM78LA opcode handlers
+
+#include "emu.h"
+#include "mm78la.h"
+
+
+// changed opcodes
+
+void mm78la_device::op_ioa()
+{
+ // IOA: output A+carry to lower half of RO pins
+ u16 mask = (1 << (m_r_pins / 2)) - 1;
+ m_r_output = (m_r_output & ~mask) | (m_c_in << 4 | m_a);
+ m_write_r(m_r_output);
+}
+
+void mm78la_device::op_ox()
+{
+ // OX: output A+carry to upper half of RO pins
+ u16 mask = (1 << (m_r_pins / 2)) - 1;
+ m_r_output = (m_r_output & mask) | (m_c_in << 4 | m_a) << (m_r_pins / 2);
+ m_write_r(m_r_output);
+}
+
+void mm78la_device::op_ix()
+{
+ // IX: output A+carry to RO pins through PLA (MM78LA)
+ u32 out = ~m_opla->read(m_a) & 0x0fff'ffff;
+ out = bitswap<28>(out, 26,22,18,14,10,6,2,1,5,9,13,17,21,25, 27,23,19,15,11,7,3,0,4,8,12,16,20,24);
+ m_r_output = out >> (m_c_in ? 0 : 14) & 0x3fff;
+ m_write_r(m_r_output);
+}
+
+void mm77la_device::op_ix()
+{
+ // IX: output A to RO pins through PLA (MM77LA)
+ u16 out = ~m_opla->read(m_a) & 0x3ff;
+ m_r_output = bitswap<10>(out, 9,7,5,3,1,0,2,4,6,8);
+ m_write_r(m_r_output);
+}
+
+void mm78la_device::op_ios()
+{
+ // IOS: set tone frequency
+ m_tone_freq = m_tone_freq >> 4 | (m_a << 4);
+
+ // state 1->2: turn on
+ if (m_ios_state == 1)
+ {
+ m_tone_on = true;
+ reset_tone_count();
+ }
+ else
+ m_tone_on = false;
+
+ // increment state machine
+ m_ios_state = (m_ios_state + 1) % 3;
+}
+
+void mm78la_device::op_int0h()
+{
+ // INT0H: toggle speaker
+ toggle_speaker();
+}
+
+void mm78la_device::op_int1l()
+{
+ // INT1L: ?
+ op_todo();
+}