04139: gradius4: "JVS NOT FOUND" error on startup

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
04139	Misc.	Trivial	Always	Dec 14, 2010, 02:05	Nov 7, 2019, 02:32

Tester	NekoEd	View Status	Public	Platform	SDLMAME
Assigned To		Resolution	Bugs That Aren't Bugs	OS	Linux
Status [?]	Resolved			Driver	konami/hornet.cpp
Version	0.140u2	Fixed in Version		Build	Normal
		Fixed in Git Commit		Github Pull Request #

Summary	04139: gradius4: "JVS NOT FOUND" error on startup
Description	Exactly as the summary says. Does not seem to affect gameplay.
Steps To Reproduce	Boot game.
Additional Information
Github Commit

Flags	Verified with Original
Regression Version
Affected Sets / Systems	gradius4

Attached Files	0001.png (1,352 bytes) Dec 14, 2010, 04:18

No.06917 Tafoid Administrator Dec 14, 2010, 05:01	This is a harmless message. It's been there since it was bootable (0.102) and will likely continue do show this message. It's related to, if my information is correct, an infrared I/O device board which converts Jamma to a JVS (Jamma Video Standard) signal. This is only hardware on newer arcade systems but is not explicitly needed for emulation purposes. My knowledge isn't gospel, so I invite anyone else who might have more (correct) information please post a note. I don't believe it should be considered a bug, though.
No.06919 Haze Senior Tester Dec 14, 2010, 15:05	Yeah, the board can be hooked up as JAMMA or JVS. This is just telling you that JVS isn't connected, MAME doesn't emulate it and uses the standard JAMMA hookup.
No.06920 NekoEd Senior Tester Dec 14, 2010, 17:01	Perhaps not considered a bug, but at least it's here for future reporters to (hopefully search for and) find before submitting it. Plus, it can be reopened if it's ever decided, for whatever reason, to emulate the JVS hardware.
No.11866 system11 Senior Tester Jul 10, 2015, 16:22	Not sure why this is still around, normal game behaviour.
No.17153 Hydreigon Tester Nov 7, 2019, 02:32	The error occurs because the main board isn't detecting an I/O MCU from certain JVS boards. The one Konami developed uses a Hitachi H8/3664 which communicates serially with the PPC403GA's serial port. Konami forgot to code the game so that it would remove the message when DIP #6 was set to "off" position (at least proving this is BTNAB behavior).