03799: junofrst: Credit during demonstration play causes graphic error

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
03799	Graphics	Minor	Always	Mar 28, 2010, 20:07	Jun 7, 2021, 10:38

Tester	Tafoid	View Status	Public	Platform	MAME (Self-compiled)
Assigned To		Resolution	Open	OS
Status [?]	Confirmed			Driver	konami/junofrst.cpp
Version	0.137u1	Fixed in Version		Build
		Fixed in Git Commit	1de6fab	Github Pull Request #

Summary	03799: junofrst: Credit during demonstration play causes graphic error
Description	This is an interesting one. When you credit while the gameplay demonstration is happening, the credit/title screen's logo gets cut off on the right side. What's even weirder is that it doesn't happen with the gottlieb version of Juno First (junofrstg).
Steps To Reproduce
Additional Information	I was able to test early mame versions and found a regression version - 0.33u6 Both 0.33u5 and 0.33u6 snaps are included.
Github Commit

Flags
Regression Version	0.33b6
Affected Sets / Systems	junofrst

Attached Files	JUNOFRST-0.33b5.PCX (13,289 bytes) Mar 29, 2010, 01:39
	JUNOFRST-0.33b6.PCX (13,301 bytes) Mar 29, 2010, 01:39
	Animation1.gif (4,699 bytes) Mar 29, 2010, 05:26

No.05923 Haze Senior Tester Mar 28, 2010, 20:20	I wouldn't be surprised if this was a real game bug, especially given that it only happens on one version. They could also have coin lockout enabled in attract mode (if it isn't already hooked up) but that would be somewhat illogical.
No.05925 M.A.S.H. Senior Tester Mar 29, 2010, 05:27 edited on: Mar 29, 2010, 05:48	Added an animated GIF. The regression version (MAME 0.33beta6) is correct. I checked it with DOSBox. The bug was not in MAME 0.33b5!
No.05927 stephh Developer Mar 29, 2010, 10:59	From src/mame/video/tutankhm.c.html : TODO: Does bit 1 of the source address mean something? We have to mask it off otherwise the "Juno First" logo on the title screen is wrong. And indeed is the "copy" flag only based on bit 0 : int copy = state->blitterdata[3] & 0x01; It would be interesting to see the difference in the code between the 2 sets as GFX1 is the same.
No.05942 robiza Developer Apr 5, 2010, 08:46 edited on: Apr 5, 2010, 08:47	it's a timing problem the interrupt draw the "juno first" logo before the screen is clear; at the end of the interrupt the "clear screen routine" continue and delete the last part of the logo MDRV_CPU_ADD("maincpu", M6809, 1500000) /* 1.5 MHz ??? */ with a higher value the bug disappear we need to know the exact clock
No.05943 M.A.S.H. Senior Tester Apr 5, 2010, 09:19	PCB info says for 2x Juno First bootlegs 1x oscillator 18.432 = 18432000 Hz. If the factor is 12, then 18432000/12 = 1.536 MHz
No.05950 robiza Developer Apr 6, 2010, 10:31	it's necessary a PCB; maybe Tutankhamon use a very similar PCB
No.18933 Haze Senior Tester Jun 7, 2021, 10:02	This still happens.
No.18935 Tafoid Administrator Jun 7, 2021, 10:38	When I tested I could have sworn it was fixed in that era - I'll have to check if/when it re-regressed. Unresolved for now.