diff options
author | 2024-10-13 17:29:10 +0300 | |
---|---|---|
committer | 2024-10-14 01:29:10 +1100 | |
commit | ec9aec11be23ad7eda6fc52d38fdf90ca6a484e2 (patch) | |
tree | 72a47d22984d1f328aee3527e9e9c85f52f2abea | |
parent | b49a1dc0102a3add9371f5ae5b610ab6877b32c1 (diff) |
bus/a2bus/suprterminal.cpp: Allow mapping control via C0Bx reads. (#12876)
C0B2, C0B4 and C0B6 react to both reads and writes according to the manual.
-rw-r--r-- | src/devices/bus/a2bus/suprterminal.cpp | 52 |
1 files changed, 34 insertions, 18 deletions
diff --git a/src/devices/bus/a2bus/suprterminal.cpp b/src/devices/bus/a2bus/suprterminal.cpp index 0cac42964b2..7f29899d0ec 100644 --- a/src/devices/bus/a2bus/suprterminal.cpp +++ b/src/devices/bus/a2bus/suprterminal.cpp @@ -75,6 +75,8 @@ private: std::unique_ptr<u8[]> m_fontram; // u8 m_fontram[0x400]; bool m_bRasterRAM, m_bCharBank1, m_bC800IsRAM; + + void access_c0nx(u8 offset); }; //------------------------------------------------- @@ -145,18 +147,7 @@ u8 a2bus_suprterminal_device::read_cnxx(u8 offset) return m_rom[offset+0x300]; } -u8 a2bus_suprterminal_device::read_c0nx(u8 offset) -{ - switch (offset) - { - case 9: - return m_crtc->register_r(); - } - - return 0xff; -} - -void a2bus_suprterminal_device::write_c0nx(u8 offset, u8 data) +void a2bus_suprterminal_device::access_c0nx(u8 offset) { switch (offset) { @@ -173,14 +164,39 @@ void a2bus_suprterminal_device::write_c0nx(u8 offset, u8 data) case 6: m_bCharBank1 ^= 1; break; + } +} - case 8: - m_crtc->address_w(data); - break; +u8 a2bus_suprterminal_device::read_c0nx(u8 offset) +{ + if (offset < 8) + { + if (!machine().side_effects_disabled()) + { + access_c0nx(offset); + } + } + else if (offset == 9) + { + return m_crtc->register_r(); + } - case 9: - m_crtc->register_w(data); - break; + return 0xff; +} + +void a2bus_suprterminal_device::write_c0nx(u8 offset, u8 data) +{ + if (offset < 8) + { + access_c0nx(offset); + } + else if (offset == 8) + { + m_crtc->address_w(data); + } + else if (offset == 9) + { + m_crtc->register_w(data); } } |