Defender Sound ROM (needed)

jetusenet

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Hi;
This is part III of my never ending quest to repair my sound PCB on my Defender.

After several more hours tracing with a probe, everything seems to work properly, with the exception of the sounds. Now I get a very strange series of misc. tones etc. when the game boots and in test, still nothing. I think that I have narrowed the culprit down to the sound ROM.

I searched the forums and came up with a file but it is in the SND format which I cannot use. Would anyone happen to have a Sound ROM1 file that they could send to me?? I would really appreciate it.......

Thanks
Jeff
 
you can't just rename that file? it looks like a regular binary, it's 2048 bytes.

about all I have is the MAME .snd file too. lol

I guess if I cared enough though I could fire up the ol' eprom programmer and dump it, but I haven't done that in a looooong time.

the "weird tones" you speak of, does it sound like a revving engine with some beep patterns? that's supposed to be the "test" sound when you press the button on the sound board.

I have 2 boardsets, when I swapped the 2nd one in I forgot to change the sound boards (doh) and that's what it did, I got no game sounds.

then I dropped the correct sound board in and uh, well... now I get sounds, but wrong sounds. still haven't reached a resolution for that one yet.
 
I am new to burning ROMs, in fact this will be my first attempt!

What would the extension have to be for the file to work correctly, can I actually just rename it for this purpose or is that file just for MAME???

I tried several time to activate the test feature on the PCB, both when the sound PCB was working and again when it was not and it does nothing, no sounds produced.

It seems to have degraded into the weird sounds after being left on in sound test, then rebooted. I just tried it again after reading your post and it worked properly for the first boot sounds, then slightly degraded for the second boot sounds then the sounds went out again......

I hit all the components with the freeze but that did not help.....

I think that it is the ROM but until I replace it I will not know for sure.

Jeff
 
oh yeah, actually the file extension shouldn't even matter, unless your software requires one for whatever reason. it's the data that matters, and like I said, that's just binary.

I honestly can't remember how to do any of it though. do you have the proper replacement rom available? cause I imagine you can't erase the one that you've got.
 
The one that's in there looks beat, I had to scrape the legs because of the black coating on them........ That one is going into the trash!

I have the ROM but I'm too tired now to do anything else tonight, a few more and then it's beddtime!

I'll have to get back to this during the week, it has already taken up too many hours of my time.

Thanks and I'll follow up when I something to report.

Peace
Jeff
 
eh, corrosion happens on roms. first thing I did on my Defender boardset was clean everything. in retrospect that may have been a bad idea, I should've have plugged it in first, but I went ahead and sanded all the chip legs.

the boardset I wound up buying didn't even work, I had to transfer my old roms over. another sad tale of a fucking waste of my time, and money, that's all.

good luck moving a dead Defender though. so, I'll just have to keep dicking around with it I guess.
 
The SND file is a BIN file renamed. If your burner software doesn't see it, then just rename it to Defsnd.bin. It was a MAME "standardization" to use the old DOS 8.3 naming and to name game ROMs by using the same name and changing the extension. They are all the same binary format under the cover.

ken
 
You shouldnt have to even rename the file. When you go to select the file in the burner software scroll down to "*" any for the file extension and you should see it. Sometimes the extension gets named to indicate snd like in your case or even what type eprom to use such as .512
 
Thank you, you guys are exactly correct, my burner recognized the file once I used the wild-card extension. Now my problem is that it is a a USB connected burner (GQ-4X) and the voltage is insufficient to burn the EPROM so now I need an external power supply......

It states that it has to be +9vdc (or greater) but I am not sure exactly what the voltage should be so I sent an e-mail to the distributor and I am patiently waiting their reply......

Thanks again guys, once I make some progress, I'll post the results.
Jeff
 
What type of ROM is it? Chip number please. I havethe GQ-4X too and I have the external power... try to burn it without it. The software usually gives the external power message. See if it verifies... if it does. Try it out.
 
Hi;
I have the GQ-4X and I am attempting to burn the MCM2716. I did try and it gave me the failure message so that indicates that I need an external power supply.
I want to get just one so I need to know what the max voltage needed is so I won't have to have a box of adapters.....
I think a +30vdc would be the max I would ever need but I am waiting for conformation before I purchase....
Jeff
 
Check you house for a DC wall power supply. The one I had from an old cordless phone works great. I don't have any 2716 EPROMs, only 2764, 27256, and 27010.
 
FWIW, a 2716 uses 25v to program - not sure if that means you need a 25v+ external power supply.
 
I don't recognize the burner number, but if it is based on the Willem design, you can go up to a 12VDC exernal supply (and you need to for NMOS chips). Get a BIG one as the voltage doubler loses voltage as it draws power. I used a 2A supply from an HP laptop and that worked fairly well for most chips.

ken
 
OK, I repaired the sound issue, it was the ROM!

I used a 1500mA 9vdc adapter which was sufficient to program a NEC D2716. I could not program the Motorola, it failed during the write.

I am very happy as this was my first sucessful attempt at burning a ROM!! I had used the burner to compare and get chksums but that was it..... Ah, the next level.....

I still have another strange issue, it credits by itself sometimes. If I turn the game on and do not play, it will just sit there, no problem. But if I put some credits into the game and play, during the game, I can hear the game crediting up. When the game is over, I can actually count to 3 and then get 4 credits, count to 3 and another 4 credits and this will go on up to 99 credits...... Very strange, it is evey three seconds.

I am going to go through the schems and see if I can trace this to a specific IC. I think that I have spent something like 8 solid hours on this PCB set to date!

Thanks everyone for your help!
Now, time to play a couple of rounds...
Jeff
 
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