Outrun missing SoundFX

MKplayer1start

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Okay so pcb works perfect except it's missing soundFX. Music & video works great.

It's definitely not the audio amp or any wiring in the cab since I have another Outrun pcb that works perfect in the cab.

All the socketed chips have been tested on another working pcb and they're all good. The pcb also passes the Rom & Ram self test all good.

I narrowed the problem down to the top board since the bottom board works with another known good top board. It should be noted I fixed graphic glitches on this board when I found 3 spots on the back of the bottom board that had bent pins touching other pins. when I separated them the graphic glitches were gone. I know to look for other bent pins, and broken traces but anything else I should look for in this type of situation?
 
Good that you found some physical damage causing some of your problems.

If you've exhausted your search for physical damange, you'll need to move on. What tool(s) do you have to proceed with diasnosis? O'scope? Logic probe? DMM?
 
Good that you found some physical damage causing some of your problems.

If you've exhausted your search for physical damange, you'll need to move on. What tool(s) do you have to proceed with diasnosis? O'scope? Logic probe? DMM?

I have a DMM and a soldering station. That's unfortunately pretty much it. I'd like to know how to check the soldered chips on the board. I have a fully working board I can compare it to if I knew how lol. Is that what a logic probe is used for?

I have a third complete boardset not working that I can take chips from if needed.
 
I have a DMM and a soldering station. That's unfortunately pretty much it. I'd like to know how to check the soldered chips on the board. I have a fully working board I can compare it to if I knew how lol. Is that what a logic probe is used for?

I have a third complete boardset not working that I can take chips from if needed.

OK, a soldering station is good for replacing parts... but you need to figure out what to replace first. A DMM is a fairly crude tool for doing so... but better than nothing.

A logic probe is a pretty simple device; all it tells you is if the pin you touch with its tip is logical "high" ("on", "1") or low (off, 0), or rapidly switching between those two ("pulsing"). It typically indicates one of those 3 possible conditions to you with LEDs (well, technically there's a 4th possibility, but we'll leave that out for now). This knowledge, along with a little bit of knowledge of what "should be going on" can help identify bad components. How to deteremine what "should be going on"... can be done either by reading and understanding the schematics and datasheets of the component in question... or by comparing to a known-good PCB if you have one. So, a working PCB to compare with isn't strictly necessary, but it doesn't hurt one bit. It allows one to be lazier and/or less knoweldgable, and still know what should be going on. All that said, in this case, some of the circuitry we're interested in is analog (not digital), so a logic probe would only limited utility (checking the trigger lines of the 4066s and the inputs to the DAC, for example).

So, do you have the schematics?
http://www.crazykong.com/manuals/Outrun.sch.pdf

Page 1 is pretty much the whole sound system for OutRun.
 
OK, a soldering station is good for replacing parts... but you need to figure out what to replace first. A DMM is a fairly crude tool for doing so... but better than nothing.

A logic probe is a pretty simple device; all it tells you is if the pin you touch with its tip is logical "high" ("on", "1") or low (off, 0), or rapidly switching between those two ("pulsing"). It typically indicates one of those 3 possible conditions to you with LEDs (well, technically there's a 4th possibility, but we'll leave that out for now). This knowledge, along with a little bit of knowledge of what "should be going on" can help identify bad components. How to deteremine what "should be going on"... can be done either by reading and understanding the schematics and datasheets of the component in question... or by comparing to a known-good PCB if you have one. So, a working PCB to compare with isn't strictly necessary, but it doesn't hurt one bit. It allows one to be lazier and/or less knoweldgable, and still know what should be going on. All that said, in this case, some of the circuitry we're interested in is analog (not digital), so a logic probe would only limited utility (checking the trigger lines of the 4066s and the inputs to the DAC, for example).

So, do you have the schematics?
http://www.crazykong.com/manuals/Outrun.sch.pdf

Page 1 is pretty much the whole sound system for OutRun.

So with these schematics and a Multi meter how would I test if a chip is bad? I somewhat understand the schematics but it's a little over my head. I'm guessing you ground one probe and then touch each pin on a chip one at a time with the red probe and each pin will or won't have a reading and it's somehow compared to the schematics?

Thanks for all the info so far man
 
So with these schematics and a Multi meter how would I test if a chip is bad? I somewhat understand the schematics but it's a little over my head. I'm guessing you ground one probe and then touch each pin on a chip one at a time with the red probe and each pin will or won't have a reading and it's somehow compared to the schematics?

First, lets see try to understand a bit about what's going on with the schematics, I'll try to keep it fairly brief:

The brains of the operation if the Z80A in the top-left corner. It's the CPU that runs the sound generating "computer". Just right of it is a 27256 (IC88)... that's the EPROM that contains all of the code that runs the Z80. And right of it you'll see a TMM2015, that's RAM that the CPU uses. Now, moving to the bottom left corner, you'll see to more TMM2015 RAMs. Those two are used by the big-and-scary "315-5128" (IC90), which is a wacky Sega custom IC that does a bunch of crap (we can only hope it isn't bad). Right of it are 6 more 27256 EPROMs; these contain the digitized sound data used to play the drum sounds, the speech, the sound of waves crashing, etc. That just leaves the middle and right regions, and the extreme right side is just amplifiers.

So... there are two primary sound generating devices here: at the top-center, you'll find a YM2151, which is a sound synthisizer chip, and it's accompanying DAC, a YM3012. Notice on the YM3012 there are two outputs labeled "CH1" & "CH2", that go out to a pair of op-amps. The foregoing, I'm pretty sure, is the hardware for generating the synthisized music in the game... which I think you said is working fine.

The other sound generation path is seen just below the first. You'll see a set of lines (a "bus") coming up from the 315-5128 to one labeled "DAC1022". That, I believe, is the DAC (digital to analog converter) for the "sound effects." All its inputs are the digital lines on the left; its output is an analog signal on pin 15. This signal (the sound), then goes thru a cap and a couple of resistors, and is split up. Each side goes thru a 4066 (essentially just a valve that allows it to be allowed thru or blocked). Notice that each 4066 has a control line going into it... one labeled LFT the other RGT. These will control if the sound effect is heard in the left channel, right channel (or both.. .or neither). The signals then go into a pair of wacky-looking "MF-50" chips. Those are just filters to remove any high-frequencies from the sound. Finally, the output of those filters (each on pin 3) go on to be mixed with the sound coming from the synthisizer path, and then amplified by LM324s.

You follow most of that?
 
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First, lets see try to understand a bit about what's going on with the schematics, I'll try to keep it fairly brief:

The brains of the operation if the Z80A in the top-left corner. It's the CPU that runs the sound generating "computer". Just right of it is a 27256 (IC88)... that's the EPROM that contains all of the code that runs the Z80. And right of it you'll see a TMM2015, that's RAM that the CPU uses. Now, moving to the bottom left corner, you'll see to more TMM2015 RAMs. Those two are used by the big-and-scary "315-5128" (IC90), which is a wacky Sega custom IC that does a bunch of crap (we can only hope it isn't bad). Right of it are 6 more 27256 EPROMs; these contain the digitized sound data used to play the drum sounds, the speech, the sound of waves crashing, etc. That just leaves the middle and right regions, and the extreme right side is just amplifiers.

So... there are two primary sound generating devices here: at the top-center, you'll find a YM2151, which is a sound synthisizer chip, and it's accompanying DAC, a YM3012. Notice on the YM3012 there are two outputs labeled "CH1" & "CH2", that go out to a pair of op-amps. The foregoing, I'm pretty sure, is the hardware for generating the synthisized music in the game... which I think you said is working fine.

The other sound generation path is seen just below the first. You'll see a set of lines (a "bus") coming up from the 315-5128 to one labeled "DAC1022". That, I believe, is the DAC (digital to analog converter) for the "sound effects." All its inputs are the digital lines on the left; its output is an analog signal on pin 15. This signal (the sound), then goes thru a cap and a couple of resistors, and is split up. Each side goes thru a 4066 (essentially just a valve that allows it to be allowed thru or blocked). Notice that each 4066 has a control line going into it... one labeled LFT the other RGT. These will control if the sound effect is heard in the left channel, right channel (or both.. .or neither). The signals then go into a pair of wacky-looking "MF-50" chips. Those are just filters to remove any high-frequencies from the sound. Finally, the output of those filters (each on pin 3) go on to be mixed with the sound coming from the synthisizer path, and then amplified by LM324s.

You follow most of that?

Ok I got off my iphone and went on a pc. Looked at the schematics and followed everything you said. I understand where all the chips you're talking about are located and everything you said about the 2nd audio path going to DAC1022 and the output from pin 15. I'm guessing what symbols on the diagram are for caps and resistors from what you're saying and I think I follow but only because you described everything step by step. otherwise I would have no idea what any of this diagram means.

I'm guessing the big-and-scary 315-5128 is big and scary cause it's a 100 pin chip and a bitch to replace? lol
 
so from your info I should be looking at the chips described in the 2nd audio path. the DAC1022 and everything in the output path from the DAC1022. Caps, resistors, 4066 and the two MF-50 chips.

so that's where you would start looking?
 
Looked at the schematics and followed everything you said. I understand where all the chips you're talking about are located and everything you said about the 2nd audio path going to DAC1022 and the output from pin 15. I'm guessing what symbols on the diagram are for caps and resistors from what you're saying and I think I follow but only because you described everything step by step. otherwise I would have no idea what any of this diagram means.

I'm guessing the big-and-scary 315-5128 is big and scary cause it's a 100 pin chip and a bitch to replace? lol

Caps, on this schematic, are 2 parallel lines with 3 slashes drawn betwen them. They're designated with a C-number. Resistors are zig-zag lines, and designated with an R-number.

No one would understand schematics unless they looked at them and studied them. I sure didn't until I began digging them out and looking at them for every game I came across.

315-5128 is big... well, because of it's size. It's scary because it's pretty much just a black-box. There's no documentation (that I know of) about exactly what it does internally, or the exact function of every pin (except what can be deduced from looking at this schematic) or any good way to test them. There are also no replacments that I know of other than robbing other PCBs. And of course, as you point out, 100 pins is no picnic to deal with.
 
so from your info I should be looking at the chips described in the 2nd audio path. the DAC1022 and everything in the output path from the DAC1022. Caps, resistors, 4066 and the two MF-50 chips.

so that's where you would start looking?

Precisely. I'd look at everything upstream (left) of where the 2 audio paths join together (are "mixed"). So R18 & R21, then the caps, the the MF50 filters, then the 4066 (it's shown in 4 different places, but there's really just 1 IC, it has 4 seperate units internally), R9, R8, C6, and then the DAC. Those are the components you'll want to look closely at.

To answer your earlier question: yes, you'll want to put the black DMM probe on a convient ground point anywhere on the board you can find it. Then carefully touch various places with the red probe. You can use both DC and AC Volts modes on the DMM. Of course, you'll need to do something with the game to cause it to try making the sound effects. Diagnostic mode is probably the easiest way to do that. (you have gone thru all the tests in diagnostic mode, haven't you??)
 
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Precisely. I'd look at everything upstream (left) of where the 2 audio paths joing together (are "mixed"). So R18 & R21, then the caps, the the MF50 filters, then the 4066 (it's shown in 4 different places, but there's really just 1 IC, it has 4 seperate units internally), R9, R8, C6, and then the DAC. Those are the components you'll want to look closely at.

To answer your earlier question: yes, you'll want to put the black DMM probe on a convient ground point anywhere on the board you can find it. Then carefully touch various places with the red probe. You can use both DC and AC Volts modes on the DMM. Of course, you'll need to do something with the game to cause it to try making the sound effects. Diagnostic mode is probably the easiest way to do that. (you have gone thru all the tests in diagnostic mode, haven't you??)

Oh good thing you pointed out I had to make the sound FX while testing. I probably wouldn't of done that lol

I did run the rom & ram test and everything was good, and I also did the sound tests and all the music plays fine but none of the sound fx work.

Looks like I'm gonna have to setup a test monitor and power supply to make it easier to work on this board and run the sound test while checking everything. I really appreciate all the help and info. I'm Pretty confident I can get this board working thanks to your explanation.

When it comes to outrun, nobody wants to repair or work on them so hopefully I can get the sound FX working myself
 
Oh good thing you pointed out I had to make the sound FX while testing. I probably wouldn't of done that lol

I did run the rom & ram test and everything was good, and I also did the sound tests and all the music plays fine but none of the sound fx work.

Looks like I'm gonna have to setup a test monitor and power supply to make it easier to work on this board and run the sound test while checking everything. I really appreciate all the help and info. I'm Pretty confident I can get this board working thanks to your explanation.

When it comes to outrun, nobody wants to repair or work on them so hopefully I can get the sound FX working myself

So, of the 18 sounds in sound test (http://www.massdestruction.co.uk/jsnes/uploaded_images/outrun_doing_great.png) which DO and which DON'T work?

The best tool for an issue like this is really an oscilloscope. Or perhaps a high-input-impedence amplifier & headphones to probe and listen for signals upstream in the circuitry. But you've only got a DMM, so we'll have to just make do. When the game makes the sound effects, things should happen in that circuit. Excatly what readings you get on your DMM will actually depend on your DMM (how fast it updates, how it averages varying AC signals, if it properly shows any DC offset with AC on top of it, etc., etc.). So my readings, with my DMM, probably shouldn't be compared to your readings with your DMM. But since you have a working board, you can compare your readings on each PCB as they'll be made with the same DMM.

Yeah, I'd just get someone else to continuously activate one of the non-working sounds in the diagnostic menu while I probed around the sound circuit.

Actually, before you get to that, you could try to make sure none of the passive components (resistors & caps) in that section are open.
 
Thanks for all the help. Im gonna setup a test bench this weekend and give it a go. I just took ouf a monitor out of a smash tv to clean the cab so I can use that monitor for testing for now
 
Outrun

I know this is Thread is very old...but wanted to ask DarrenF where i should test my outrun board as i have no sound and a graphic issue.

What i know...

I have an outrun Turbo PcB that plays perfect with sound.
This means power supply , harness, amplifiers and inputs all work 100% in the cab.

Upon plugging in the Outrun board with issue.. I have a high pulsing clocking sound.
the sound pulses in time with the background flickering on the graphics (background glitches).

In test mode;

all memory tests = pass
in sound = silence

I have swapped all roms on this board with new ones (new box set) and still have the same issue, so believe the issue to be on the board or sockets.

If I turn the volume up I can here pulsing with start button flashing and with graphics changing from game play to start screen...could be just loud ground noise..(not a hum)
Im wondering if there is a mixing summing amplifier that has died or if there is no output data triggering the sound or midi synth chip.

Thinking maybe ic139 good place to test.....seems to work as I just replaced IC88 10187 with eprom from turbo outrun epr-12300 ..this output garbled speech..so that tell me that at least the output of this section is working..

I have a scope and a dvm.

thank you!
 
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I know this is Thread is very old...but wanted to ask DarrenF where i should test my outrun board as i have no sound and a graphic issue.

What i know...

I have an outrun Turbo PcB that plays perfect with sound.
This means power supply , harness, amplifiers and inputs all work 100% in the cab.

Upon plugging in the Outrun board with issue.. I have a high pulsing clocking sound.
the sound pulses in time with the background flickering on the graphics (background glitches).

In test mode;

all memory tests = pass
in sound = silence

I have swapped all roms on this board with new ones (new box set) and still have the same issue, so believe the issue to be on the board or sockets.

If I turn the volume up I can here pulsing with start button flashing and with graphics changing from game play to start screen...could be just loud ground noise..(not a hum)
Im wondering if there is a mixing summing amplifier that has died or if there is no output data triggering the sound or midi synth chip.

Thinking maybe ic139 good place to test.....seems to work as I just replaced IC88 10187 with eprom from turbo outrun epr-12300 ..this output garbled speech..so that tell me that at least the output of this section is working..

I have a scope and a dvm.

thank you!

It's not clear from your description if the OutRun (not Turbo OutRun) board boots OK and has good graphics. I.e., can you play it just fine, without sound?

If so, then everything on the 68000-side of the board would seem to be working fine, and you're just looking at the Z80-side for sound. The most fundamental things there are the CPU (the Z80) and the sound code EPROM (the one that sits right beside the CPU, not the 6 in a row... those are sound sample data). First, give the area a GOOD look over, using magnification. Look for broken traces, burns, deep scratches, bent pins in socketed ICs, ICs inserted backwards, prior repairs,etc etc. If that doesn't turn up anything: Swap out the Z80 with a good one; and pull & verify (or swap out with good) the EPROM.
 
It's not clear from your description if the OutRun (not Turbo OutRun) board boots OK and has good graphics. I.e., can you play it just fine, without sound?

If so, then everything on the 68000-side of the board would seem to be working fine, and you're just looking at the Z80-side for sound. The most fundamental things there are the CPU (the Z80) and the sound code EPROM (the one that sits right beside the CPU, not the 6 in a row... those are sound sample data). First, give the area a GOOD look over, using magnification. Look for broken traces, burns, deep scratches, bent pins in socketed ICs, ICs inserted backwards, prior repairs,etc etc. If that doesn't turn up anything: Swap out the Z80 with a good one; and pull & verify (or swap out with good) the EPROM.

Hi DarrenF

My board sets graphics are almost there but has a strobeascopic flickering to it in parts of background data.

I have swapped all the chips out as suggested but still are getting no sound at all
No samples
no synth chip play back
 
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