06763: bbcm : Testing some demos on BBC Master 128!

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
06763	Misc.	Major	Always	Nov 18, 2017, 21:22	Apr 17, 2018, 19:49

Tester	demotester	View Status	Public	Platform	MAME (Official Binary)
Assigned To	Pernod	Resolution	Open	OS	Other
Status [?]	Assigned			Driver	acorn/bbc.cpp
Version	0.191	Fixed in Version		Build	32-bit
		Fixed in Git Commit		Github Pull Request #

Summary	06763: bbcm : Testing some demos on BBC Master 128!
Description	1) Demo 128 by The Master --> http://www.pouet.net/prod.php?which=56807 - runs fine till loading the 2nd part where hangs! 2) Some Nasty Effects by CRTC --> http://www.pouet.net/prod.php?which=66197 - timing problems! (Note: Check a video captured on a real hardware on pouet link above!) 3) Mode Infinity by CRTC --> http://www.pouet.net/prod.php?which=61849 - timing problems! (Note: Check a video captured on a real hardware on pouet link above!) 4) The Master of Your Old School --> http://www.pouet.net/prod.php?which=55785 - timing problems! (Note: Check a video captured on a real hardware on pouet link above!) 5) Teletextr --> http://www.pouet.net/prod.php?which=70465 - does not start! (Note: Check a video captured on a real hardware on pouet link above!) 6) Sugar Smash --> http://www.pouet.net/prod.php?which=67796 - does not start! 7) Redistribution --> http://www.pouet.net/prod.php?which=53827 - does not start! (Note: This demo is for BBC B model, but should work also on a Master 128 model!)
Steps To Reproduce	Start the BBC Master 128 driver and insert one of above demos! In running driver press SHIFT + F12 to boot the demo!
Additional Information	All demos tested to work fine on B-em v2.2 emu! (Model: Master 128, Video display type: Interlaced, Borders: Full.) NOTE: On a real machine the BREAK key act as a reset and the ESCAPE key act as a break - what is same on MAME/MESS where F12 act as a BRK key. The problem is now only with the function of F3 key when not in full key mode, as it usually hangs the emu?
Github Commit

Flags
Regression Version
Affected Sets / Systems	bbcm

Attached Files

No.14445 Pernod Developer Nov 19, 2017, 21:29	All bbc machines are currently marked MACHINE_IMPERFECT_GRAPHICS, and all of these demos rely on video timing and full handling of the 6845 CRTC.
No.14446 demotester Tester Nov 19, 2017, 21:48 edited on: Nov 19, 2017, 21:53	At least graphics on the demo 1) seems to not be a problem, but for some others it definitely yes. The testing of demos documents what demos currently at least partially working and what dont. Hope it could be of help in future developement in improving the CRTC driver timings. Not sure are you aware of F3 key problem while in partial keyboard mode!? (It crashes the emu!) I guess it should behave same as F12 key while in full keyboard mode!
No.14447 Pernod Developer Nov 19, 2017, 22:00	I'll take a look at the F3 issue, wasn't aware of that. Many of these demos really push the CRTC to it's limits, as do some games. They change the screen dimensions and resolution per scanline which requires exact timing of interrupts. I've looked at improving the graphics a few times but haven't yet managed to get things right, it's high on my list though.
No.14448 demotester Tester Nov 19, 2017, 22:18 edited on: Nov 19, 2017, 22:18	All demos have been tested to work fine on B-em v2.2 emu! (Model: Master 128, Video display type: Interlaced, Borders: Full.) So it is currently the only emu that can handle all mentioned demos pretty close. Now not sure is it same possible on MAME!? (regarding needed accuracy) But hope at least it could be improved more than it is now, if comparing with some other 'mature' drivers.