Sound Problem With Major Title 2 to R-Type Leo Irem M-92 Conversion

[ShootTheCore]

I have an Irem Major Title 2 board that I'm converting over to R-Type Leo by following the directions in the thread here: http://www.jammaplus.co.uk/forum/fo...rem-m92-major-title-2-to-rtype-leo-conversion

I've carefully followed the instructions step-by-step. The game boots up and looks and plays perfectly, but there's sound problems with the final output. In the sound test, all of the music tracks play their base track (with some details missing), and only two sound effects in the entire list work. Any ideas? Here's details and troubleshooting steps I've tried so far:

* The donor Major Title 2 worked perfectly beforehand.

* The checksums on all of the files check out against the checksums listed in the directions.

* The checksums on the two sound ROMs verify against the source files.

* I tried using two different ROM EPROMS for the sound - same symptoms with both pairs of chips.

* I replaced the capacitors on the board with fresh ones. Verified continuety with the multimeter on each capacitor with its circuit.

* Double-checked every jumper setting with the full list of jumpers listed in the directions.

* Verified continuety on every jumper setting with the multi-meter.

* Verified that my Major Title 2 board uses the same Nanao 08J27291A7 017 9227NK700 sound CPU that the conversion author had on his board.

I'm taking a break on it for now. I'm considering testing out the Main Program EPROMs next, and if that doesn't help, switching it back to Major Title 2 again and double-checking that the board is still fully functional there. Any other suggestions?

 

[xodaraP]

What speed are your EPROMs? If the sound ROMs you burnt aren't fast enough you'd run into these issues

You said the checksum matches the source files, does that checksum match up with the post patch checksum on the tutorial page?

 

[ShootTheCore]

What speed are your EPROMs? If the sound ROMs you burnt aren't fast enough you'd run into these issues

You said the checksum matches the source files, does that checksum match up with the post patch checksum on the tutorial page?

I reused the sound ROMs from Major Title 2 which are rated at 150ns. When those didn't work, I flashed a new set rated at 120ns. No difference either way. Good suggestion though!

As for checksums, yes the checksum on the ROM matches the post patch checksum on the tutorial page.

 

[ShootTheCore]

Is it a problem if the EPROMs in another bank are a different speed? Most of the EPROMs I'm using are 120ns, but the 27C040s for graphics data are 150ns.

The game looks and plays fine, but maybe the different speed chips are causing a subtle timing glitch? Dunno-just brainstorming here.

 

[ShootTheCore]

Well, I just swapped it back over to being Major Title 2 again, and everything seems to work 100%. All of the music and sound effects work fine. At least I can rule out messing something up during the capacitor swap.

I'll try blanking and reprogramming all the ROMs for R-Type Leo tomorrow and try it again.

 

[Mitsurugi-w]

Do you have pictures of your jumpers?

 

[ShootTheCore]

I got it working-Happy Day!!! I went back and verified all of the game EPROMs one by one. I had verified each one when I first programmed them, but now the EPROM for IC 8 (Digital Audio) flunked verification. Somehow that one went bad between programming and installing it on the board. Swapped it out for a freshly programmed substitute and all is well! Thanks for the suggestions everyone!