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rm/rm380z.cpp: Use real character ROM for COS 4.0, correct screen resolution and add support for user defined characters
I've managed to obtain a dump of the real character ROM for COS 4.0 courtesy of the Research Machines user group, and this PR pulls this in and updates the display code to use it.
What is the correct process for updating a rom set? This my working version that includes the new character rom:
The real characters are actually larger than the fake set we used before (8x10 rather then 5x9) and even include 2 extra rows to be used when the underline attribute is set. This all makes the display handling much easier and improves the display greatly.
So with these characters 80 column mode has a display resolution of 640x240 and 40 column mode uses 320x240.
For COS 3.4 I've set the display resolution to 240x240 which I think is correct because COS 3.0 only supported the VDU40 adaptor which uses the TI 74LS262 character ROM. These characters are 5x9, padded to 6x10 for display. It's a shame we don't have the real ROM for this as well, but at the moment I'm concentrating on getting COS 4.0 to work properly anyway!
The new ROM only includes characters 0x00 to 0x79 because the additional teletext characters (0x80 to 0xFF) are actually generated by COS as user defined characters. I've also added support for user defined characters so that these continue to work.
This PR includes all my changes for HW scrolling from the last PR which is still in review (https://github.com/mamedev/mame/pull/12014), but I don't want to close that until the review comment has been cleared. I can do any further re-work under this PR.
Just fixed a logic error with my underline attribute check. I was only swapping the last row (instead of the last two rows) when underlining. Visually it made no difference as only the last row is normally different, but still a bug! Everything should be ok now and this is ready for review.
This does look like a big simplification that will be nice to get in.
Great, thanks for reviewing @cuavas. I've addressed your comments so should be good to go in now. Do I need to do anything to make the updated romset available? It's attached to this PR.
Usually, the way to submit data/roms is by following this guide: https://wiki.mamedev.org/index.php/Submitting_Source_Code#Submitting_ROM_or_disk_dumps
Usually, the way to submit data/roms is by following this guide: https://wiki.mamedev.org/index.php/Submitting_Source_Code#Submitting_ROM_or_disk_dumps
Thanks @simzy39, I've followed that guide and emailed the rom.