From ec9aec11be23ad7eda6fc52d38fdf90ca6a484e2 Mon Sep 17 00:00:00 2001 From: Roman Donchenko Date: Sun, 13 Oct 2024 17:29:10 +0300 Subject: 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. --- src/devices/bus/a2bus/suprterminal.cpp | 52 ++++++++++++++++++++++------------ 1 file 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 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); } } -- cgit v1.2.3