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-rw-r--r--src/devices/bus/vcs/dpc.cpp14
1 files changed, 1 insertions, 13 deletions
diff --git a/src/devices/bus/vcs/dpc.cpp b/src/devices/bus/vcs/dpc.cpp
index 78faf9d9874..524013c3d9b 100644
--- a/src/devices/bus/vcs/dpc.cpp
+++ b/src/devices/bus/vcs/dpc.cpp
@@ -127,6 +127,7 @@ READ8_MEMBER(dpc_device::read)
{
case 0x00: // Random number generator
case 0x02:
+ m_shift_reg = (m_shift_reg << 1) | (~(((m_shift_reg >> 7) ^ (m_shift_reg >> 5)) ^ ((m_shift_reg >> 4) ^ (m_shift_reg >> 3))) & 1);
return m_shift_reg;
case 0x04: // Sound value, MOVAMT value AND'd with Draw Line Carry; with Draw Line Add
m_latch_62 = m_latch_64;
@@ -291,16 +292,3 @@ WRITE8_MEMBER(a26_rom_dpc_device::write_bank)
else
a26_rom_f8_device::write_bank(space, offset, data);
}
-
-DIRECT_UPDATE_MEMBER(a26_rom_dpc_device::cart_opbase)
-{
- if (!machine().side_effect_disabled())
- {
- uint8_t new_bit;
- new_bit = (m_dpc->m_shift_reg & 0x80) ^ ((m_dpc->m_shift_reg & 0x20) << 2);
- new_bit = new_bit ^ (((m_dpc->m_shift_reg & 0x10) << 3) ^ ((m_dpc->m_shift_reg & 0x08) << 4));
- new_bit = new_bit ^ 0x80;
- m_dpc->m_shift_reg = new_bit | (m_dpc->m_shift_reg >> 1);
- }
- return address;
-}