* Started graphics refactoring
* myb3k.cpp: refactored graphics circuit and added color in 320x200 mode
* myb3k.cpp: fixed speed issue by reducing CPU clock by 50% as suggested by RAM waitstates in the schematics where the CRTC uses the other 50%
* myb3k: fixed text scrolling
* myb3k: -ramsize now supported with 128K option and 256K default
* myb3k: 80 character mode added, eg 640x200
* Emulate the INT7 pull down and up for the keyboard. Initial support for JB3000 keyboard.
* myb3k: Added hi-res 640x400 mode and crude cursor support for 40 character mode
* Keyboard improvements using BACKSLASH2 keycode.
* myb3k_fdc.cpp: addressed review comment
* myb3k.cpp: Added initial monochrome monitor support
* myb3k.cpp: Adjusted the monochrome color palette to match the 525Nm of P39 phoshor in the Ericsson DU4721 monochrome monitor
* myb3k.cpp: added printer support and completed interupt support including jumper settings
* myb3k.cpp: Added softlist for Ericsson step/one
* myb3k.cpp: cleanup and srcclean:ed
* myb3k.cpp: Fixed crude support for 36x25 color text mode
* Fixed build
* myb3k_fdc.cpp: fixed review comment
* mybr3k: fixed DOS 2.11 boot in 256KB mode
* myb3k.cpp: Added graphics mode 0 which have the peculiar characteristic of different resolutions depending on the monitor used (2 connectors)
* myb3k: Separated keyboards into separate device implementations.
* myb3k: addressed review comments
* Fixed Agress offsetted text layer, worked around initial VRAM check;
* Converted to SCREEN_RAW_PARAMS and fixed visible area for Agress and Block Out;
* Fixed input labels and hookups, following manual and in-game descriptions;
Beware, the device context does not follow in MCFG_FRAGMENT_ADD
anymore due to the prototype change. So creating a device then
configuring through a fragment doesn't work as-is. The simplest
solution is just to add a MCFG_DEVICE_MODIFY at the start of the
fragment with the correct tag.
* Radica 6502: some hacks to improve the video, lack of test cases / makes these tricky to figure out properly
* at least these aren't *my* bugs.. (nw)
* radica 6502 tvgames: identify where gfx are coming from in each of the games in the space invaders pack so we can attempt to find the register that controls it, or dma etc.
new NOT WORKING
Tetris (Radica, Arcade Legends TV Game) [Sean Riddle, Incog]
* this seems to be gfx base (nw)
* latest findings (nw)
* trying to work out what these are (nw)
* typo (nw)
* this looks like some kind of dma or sound (nw)
* this seems to be mode select (nw)
* qix isn't so special, m_hackmode no longer needed (nw)
* pretty sure these are the palettes.. format is a mystery tho
* palette select bits in 4bpp mode (taito logo, game selection) palette format is still wrong tho.
* palette/tilemap dma, improves tetris (nw)
* various updates, no functional change (nw)
* notes (nw)
* radica6502 : preliminary sprites
* formatting (nw)
* sprite flipping for space invaders ufo (nw)
* Radica 6502: add scroll regs so that Phoenix can start, enemy placements are broken tho (nw)
* clearly sound related (nw)
* fix DMA for Phoenix enemy placement (nw)
* need to treat this as an RNG for collisions to work on Phoenix Stage 3
* palette is some form of hsl
* document some flaws in the actual product (nw)
