New question on Spy Hunter/MCR

modessitt

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Since no one bothers to respond to my other thread, I figured I'd start a new on so that MAYBE someone with knowledge would HELP!!!

Problem: I am bench testing, but do not have the amp setup here for the sounds. Game boots fine with no errors. However, if I go into diagnostics by flipping Dip #1 and then reset, I get a "Sound Board Interface Error" before it goes to the attract mode. It used to do this in regular mode before I replaced the Z80.

Question: Am I getting this error because the cheap squeak or dual amp is not connected? I don't want to go all the way out to the machine only to find my sounds don't work.

Maybe I should fire up the audio probe and listen for sounds on the MCR sounds pins?
 
Audio probe proved inconclusive. I get a squealing tone that seems to change pitch, but can't tell if it's a data line that gets interpreted by the dual amp or the cheap squeak or not.

I also tried swapping in five different SSIO's, using four different sets of socketed chips that I rotated through them, and they all do the exact same thing.

So - is it working normally? Guess I'll find out when I take it to the game...
 
I am pretty sure the SSIO board puts out line level audio and the satellite board just amplifies. Got an ear bud you can hook up to the audio out on the SSIO?
 
Audio probe proved inconclusive. I get a squealing tone that seems to change pitch, but can't tell if it's a data line that gets interpreted by the dual amp or the cheap squeak or not.

I also tried swapping in five different SSIO's, using four different sets of socketed chips that I rotated through them, and they all do the exact same thing.

So - is it working normally? Guess I'll find out when I take it to the game...

Mod, I've got a Spy Hunter in the shop. Give me a few hours....for me to get there, and I'll fire it up with that stuff disconnected and see what it does.

Edward
 
Since no one bothers to respond to my other thread, I figured I'd start a new on so that MAYBE someone with knowledge would HELP!!![/quote

Problem: I am bench testing, but do not have the amp setup here for the sounds. Game boots fine with no errors. However, if I go into diagnostics by flipping Dip #1 and then reset, I get a "Sound Board Interface Error" before it goes to the attract mode. It used to do this in regular mode before I replaced the Z80.

Question: Am I getting this error because the cheap squeak or dual amp is not connected? I don't want to go all the way out to the machine only to find my sounds don't work.
That's expected.... There are two CPUs among this 3 board stack. The cpu/video run the game, and the ssio runs the sound. These two CPUs can communicate with each other using a shared memory chip. For example game CPU writes a command into the memory, sets a wakeup signal, then sound CPU knows to read out a command. Same thing in the opposite direction to send a response message.

During startup the game CPU tries to initialize the sound CPU by writing a few commands that have an expected response. If the the game CPU doesn't get the expected response then it displays "Sound Board Interface Error", assumes the sound CPU is broken or disconnected, and you won't get sound. Note: controls may still work fine. Even though the connectors are physically on the ssio board, they're connected to the game CPU.

So... when you have that switch flipped, the sound CPU is in diagnostic mode and will not respond to sound generation commands from the game CPU. That's why you see the error and need to keep that switch off for normal gameplay.

You're bench testing right? Put the game in test mode run the sound test (all sound effects) and the channel test (all 6 channels). If both behave correctly your game is pretty much working.
 
Audio probe proved inconclusive. I get a squealing tone that seems to change pitch, but can't tell if it's a data line that gets interpreted by the dual amp or the cheap squeak or not.
Continuing my reply.... that was flipping the DIP switch and using the built-in diagnostic? I don't use that built-in test. I've never found documentation so I have no way of knowing if that's expected behavior or not. Better tests:

- If the gameboard is running without "Sound Board Interface Error" then flip the game's test switch and run the sound tests from the menu. Verify all sounds work. Verify all 6 channels work.

- Alternately burn the sound test ROM (link) which programs each AY8910 to output 3 channels of continuous square wave. This makes it really easy to trace a known signal all the way from the AY8910 to the LM3900 without constantly hitting buttons on the control panel. Note: sound only gets unmuted when testing one of the AY8910s, so you'll hear the "bzzz" on the speaker when running one test but not the other.

- If the gameboard shows "Sound Board Interface Error" then the sound CPU isn't running properly (cpu, rom, or ram fault) or communication between main and sound is faulty (ribbon cables, shared RAM, select lines, etc). Ideally use a Fluke 9010A to test the RAM and checksum the ROM. If you don't have that tool, then burn the sound test ROM and try the RAM test to verify the sound CPU is running at all.

The "dual amp" board is a dumb line-level audio amplifier so it doesn't interpret anything and cannot force an error message. Expect line-level audio past the LM3900 at the SSIO audio connector... assuming your soundboard is working and the volume pot is connected and adjusted properly.
 
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Fired my Spy Hunter up with just power and video signal connected. No error message (as Joey stated).

Edward
 
I also got no error message when firing it up- only in diagnostics which I have now found is normal.

Apparently I wasn't getting sound because I didn't have the volume pot hooked up. I put the boards in the cab and they fired right up and all sounds and controls work just fine.

Now - is there a free play mod/hack/hi-score save for it?
 
I don't own a Spy Hunter so I have no idea, but there's a free play ROM hack on this page (link).

High score is already saved by the original hardware if you have battery power coming from the original power supply. If that's not an option then read this thread (link) which describes substituting a Dallas battery backed SRAM.
 
High score is already saved by the original hardware if you have battery power coming from the original power supply. If that's not an option then read this thread (link) which describes substituting a Dallas battery backed SRAM.

Thanks.

It's had an MCR adapter put in, o I don't if they have the save capability the original MCR PS's had...
 
I don't own a Spy Hunter so I have no idea, but there's a free play ROM hack on this page (link).

Looks like there are a couple mods on there I can use. Thanks!

The only problem is that they tell you that you have to "patch" the ROM file, provide you with a patcher program, but don't mention ANYTHING about how to do it...
 
Thanks.

It's had an MCR adapter put in, o I don't if they have the save capability the original MCR PS's had...

Yeah, they usually have a battery on board that does it. They also completely suck in Spy Hunters and you almost always end up with loud HUMMMM in the audio as a result.
 
Looks like there are a couple mods on there I can use. Thanks!

The only problem is that they tell you that you have to "patch" the ROM file, provide you with a patcher program, but don't mention ANYTHING about how to do it...

If you're referring to the freeplay hack, I just burned a few of these for Sideways_Bongos in this thread: (2 eproms)

http://forums.arcade-museum.com/showthread.php?t=215260

He posted the files there for me to burn, they were already patched..so if you can grab and burn the eproms you're good. You just need (2) 2764 eproms. He mentioned they worked perfectly when he got them.
 
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