08042: finalapr, finalapr1, finalaprj: Flagman doesn't do his job

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08042	Graphics	Minor	Always	Jul 29, 2021, 04:31	Aug 3, 2021, 10:12

Tester	Cow	View Status	Public	Platform	MAME (Official Binary)
Assigned To	Kale	Resolution	Fixed	OS	Windows 10 (64-bit)
Status [?]	Resolved			Driver	namco/namcofl.cpp
Version	0.234	Fixed in Version	0.235	Build	64-bit
		Fixed in Git Commit	e4963f1	Github Pull Request #

Summary	08042: finalapr, finalapr1, finalaprj: Flagman doesn't do his job
Description	The dude at the end of a race is supposed to wave a chequered flag. but in MAME, he does nothing
Steps To Reproduce	Finish a race
Additional Information
Github Commit

Flags	Verified with Original, Verified with Code
Regression Version
Affected Sets / Systems	finalapr, finalapr1, finalaprj

Attached Files	Mame 2021.07.28 - 23.25.26.07_Trim.mp4 (2,573,852 bytes) Jul 29, 2021, 04:31 Uploaded by Cow

No.19126 MetalGod Senior Tester Jul 29, 2021, 08:29	I've checked some old mame videos. It seems this animation has never been emulated.
No.19127 Haze Senior Tester Jul 29, 2021, 10:41	very strange bug I have to say. I wonder if it's some glitch that happens when machines aren't linked, or maybe a strange protection. could be another missing video feature, but I'm struggling to think how. could also finally be a CPU bug
No.19131 Kale Developer Aug 2, 2021, 20:29	Used finalaprj as base: Routine at 0xc2f0 draw tiles for the flagman. It reads location $bed5a which is never updated by the i960 code, it effectively changes the flag position in 8 step chunks. The only place where it writes data there is at 0x1309c: going backward it looks like that there's a read bit 1 at 0x3460 in network area ($30380002) where branch is never taken. If this branch is taken then game effectively updates the timer but also checks if bit 7 of the exact same network port is disabled at 0x34f0, otherwise tight loops. TL;DR: network flags must be in "empty" state for non-linked machine to fix this.