Q-bert controls software asjustment ?

[jcroach]

Ahofle: THAT SUCKS !!!  Is it fixed in 1.06 ?

Nope it's still broken. 
I opened a bugreport on mametesters back when it happened, but I'm sure it isn't a priority for them.  I actually did a diff on the source code between v104 and v105 and saw some LED stuff that changed, but nothing that looked obviously wrong to me.  I really need to get a source environment and compiler setup.

Does this include the flashing Player 1 start and Player 2 start [Num Lock] and [Caps lock] LEDS

Yep, that's exactly what's broken.   

DAMN.  I just upgraded from 0.95 to 0.105  I'm going to have to find a copy of 0.104 or my atari volcano buttons are going to go to waste..............

[Level42]

Actually, thinking about it, even though the solenoids are rated 27V doesn't that mean it takes 27V to trigger them?  So 30V is probably safe for them.  All you are doing is powering up a coil of wire to make an electromagnet.  I know someone recently asked me if a resiter is needed to knock 30V down to 27V.  This isn't a LED that will burn out quicker, just an electromagnet.

Level42, I like that design.  If you find the right parts I would probably go with that.  It would be a fast mechanism to.

Well, first: the 3 Volts more or less won't matter much. The coil is getting a very short pulse only. I bet it never actualy reaches the full 30/27 Volts but at those ratings 3 Volts doesn't really matter much, and indeed it's a coil getting the voltage, nothing very delicate. No need for resistors.

Indeed, this will be a lot faster then a relay, my feeling is a relay won't work because of the short pulse.

This is what Brad says in his e-mail to me:
______________________________________________________________
The triggering needs to last a mere fraction of a second.  A half second is
wayyyyy too long.  In my Q*MAME code, it is turning on the LED and turning
off without any delay at all.  It should be the least amount of time
possible.  I didn't want to use a relay because I thought it would be more
likely that a relay could get stuck in the ON position, which would not be
good.
______________________________________________________________


Thanks, I do hope it works though Gotta build it first but the 30 Volts on the Base of the darlington (through the optoisolator) worries me a bit. I think it'll need a resisitor there.

[Level42]

I updated me design with an extra (much needed !!!) resistor. It's still a DESIGN only, not built yet and not tested !!!

[SirPoonga]

I will definately go your route though if the signal in the real game which lasts that long can trigger a solenoid it can trigger a relay.  It's all electromagnets anyway:)

[juggle50]

Nice work Level 42!!!  I don't have a clue what your diagram means as I am a Theatre Major/ Philosophy minor but it's clear you know your stuff and I feel a bit sheepish about trying to give you help before when you clearly know way more than I do.

So I'm a little confused now.  I would still like to try the set up using a ledwiz.  In your opinions (Sir Poonga and Level 42) should I or should I not use a relay?  And if I don't, what should I use instead.  I was kind of looking forward to the simplicity of the relay diagram as I don't feel comfortable building a board.

I ordered my resistors to knock the 30 volts down to 27 but it's pretty clear now that those won't be necessary so I won't worry soldering them on.

thank you for your help

[SirPoonga]

Level42, why is the darlington in there?  Don;t we need to just switch the coil on and off.  Wouldn't the optisolator do that?

[2600]

Level42, why is the darlington in there?  Don;t we need to just switch the coil on and off.  Wouldn't the optisolator do that?

I think it's because he is copying some designs and literally throwing an opto-isolator in there just in case.  As it is now, I think the circuit is going to risk blowing the darlington up and doesn't have the otpo really hooked up correctly anyways.  Also, the opto isn't spec'd so maybe it can't support enough current to drive the coil.

Level42, try keeping the topic to one thread and it may be easier to help.

[Level42]

Level42, why is the darlington in there?  Don;t we need to just switch the coil on and off.  Wouldn't the optisolator do that?

No, the optoisolator will not be able to handle such high currents.
There actualy are optoisolators with darlingtons around, but none of those still have the specs of the 6N6044, else I would have gone that route.

[Level42]

Level42, why is the darlington in there?  Don;t we need to just switch the coil on and off.  Wouldn't the optisolator do that?

I think it's because he is copying some designs and literally throwing an opto-isolator in there just in case.  As it is now, I think the circuit is going to risk blowing the darlington up and doesn't have the otpo really hooked up correctly anyways.  Also, the opto isn't spec'd so maybe it can't support enough current to drive the coil.

Level42, try keeping the topic to one thread and it may be easier to help.

Mmmm.....the reason why the darlington is in there is that it was there in the original design by Brad (see http://members.cox.net/brado426/build.htm), which in itself is basicaly a copy of the original Q*bert's triggering circuit. You can read my reponse to SirPoonga for the reason why it is still needed in my diagram.

I've never claimed to invent something new here !!!!

I merely try to make the diagram a bit safer. The reasons why I "literally throw in" an optoisolator are already spelled out in this thread, but you don't seem to care to read it, so I'm not going to repeat them here.

So back to the facts:
Can you explain me why you think there is a risk of blowing up the darlington ?
Can you explain me why the opto isn't hooked up correctly and how should it be hooked up in your view ?

Again proof that you haven't read the full thread: The opto isn't spec'd because I don't know WHICH opto to use yet, BECAUSE I need to find one that can handle the voltage (the current is NOT the issue here, if you really understand anything about electronics, you know that the current through the base of the darlington is now limited by R2).

Any help is very much wanted and appreceated, but just posting some negative remarks without any facts WHAT is wrong in my design is not what I am calling help.

Just to be very clear: I am PROPOSING an improvement on an existing WORKING design. Build the design by Brad, and it will work. MY improved design is still theory only, not built and tested yet.


EDIT: attached the full jpg here, that may be a bit clearer than linking the image.

[SirPoonga]

Just to be very clear: I am PROPOSING an improvement on an existing WORKING design. Build the design by Brad, and it will work. MY improved design is still theory only, not built and tested yet.

I can follow a schematic, I can build from a schematic, I'm not good at coming up with circuit designs.

I see a couple of differences between the qmame design and yours.  Like fuse on opposite side and the added cap.  Why? 

[Level42]

Hey SirPoonga,

That posting was in response of 2600's posting, not yours.

I'm in your league normaly, not the designer !

Those differences were copied from the diagram of John from John's Retro Arcade this site:
http://www.johnsretroarcade.com/hardware_knocker.asp

Read this page, it has a LOT of interesting info, like a patcher to give new versions of MAME the knocker triggering ability (don't know if it still works though !)

As John mentions on his site, this is actualy part of the original Q*bert diagram ! Hence the cap and the fuse placing.

I think it'll work fine without the cap. Must be some filtering or something, not really sure. The fuse is placed behind the coil of the knocker (looking from the 30V supply) in John's design and on the other side in Brad's design. It really doesn't matter, since the current is exactly the same on both sides so if it gets too high, the fuse will blow and disconnect it from the 30V from either side.

John also brings forward another important thing: the LED could be turned on for a longer period of time if the PC is in normal "PC" mode and you hit the caps lock. This will continuesly power the knocker and that's not a good thing to do. He included a switch to simply turn off the knocker alltogether. Crude but efficient.

[SirPoonga]

That posting was in response of 2600's posting, not yours.

Yep, I know

John also brings forward another important thing: the LED could be turned on for a longer period of time if the PC is in normal "PC" mode and you hit the caps lock. This will continuesly power the knocker and that's not a good thing to do. He included a switch to simply turn off the knocker alltogether. Crude but efficient.

Which is why I suggest using the LEDWiz    Don't want the LEDWiz for only a qbert knocker, use powermame or a frontend with controls.dat *sneaks a plug*.

[2600]

John's Retrocade tried to copy Q*bert Schematic, but I think he might of just misread the schematic slightly.  At least that's what it looks like. The knocker circuit spans multiple pages and if you put it all together it goes left to right 30V ->fuse-> knocker-> Main board.  The fuse and knocker are on one page, the 30V is on another.

The .1 uF cap is for filtering, debouncing.  Why the QMAME's circuit doesn't have it I dunno.  It's not "required" just a better circuit design to include it.

1. Can you explain me why you think there is a risk of blowing up the darlington ?
2. Can you explain me why the opto isn't hooked up correctly and how should it be hooked up in your view ?

1. Your putting 30V onto the Base pin of the transistor.  Please, don't try to back that up with, I'm using a 33000000 Ohm resistor, that's just ugly.
2. You should pull the emitter of the opto down with a resistor.  When the circuit is off the Base pin of the Darlington should be 0 Volts not left floating.

Additions:
1. I'd put the fuse on the high side of the knocker.
2. The resistor on the driving side of the optoisolator should be spec'd when you pick the optoisolator, otherwise it's just an arbitrary number.

[juggle50]

Well, my knocker came today.  I got it, the 30 volt power supply and I don't have a clue what to do.  Should I give the relay a shot with the ledwiz or sit on it for a bit?

[Level42]

Sure as long as that relay can work on 5 volts and use very little current you could try it, what relay are you intending to use ?

[juggle50]

Thanks for the reply Level.  I was going to use this one.  I've never used a relay before, but I think this is the one that sir poonga recomended.  Did your knocker arrive?

http://www.radioshack.com/product/index.jsp?productId=2062478&cp

[SirPoonga]

I think this is the one that sir poonga recomended.

I will tell you why I recommend it, I hope I am reading this correctly.  Someone can correct me if I am wrong.

It seems like it takes 5V/1A it activate.  The switched side can take 60V.  Not sure if the amps is good though.

[2600]

Juggle50,

You need a diode across the relay and you should get a fuse as well.

When setting up and testing DO NOT hook up the knocker, or anything on the output of the relay for that matter.  You will be able to hear the relay.  You need to get the relay to ONLY trigger when you need it to, a quick on-off.  You DO NOT want it to go "rat a tat tat".  This will require testing and a little patience.

The relay is fast, but may be a bit weak and a it's a little fragile.  It only takes a few milliamp to activate it, like 20ma.  I think they might have some information wrong on their site or I'm misreading it..  It can only handle .5 Amp or 10Watts and you are probably going to go over that.  Doubt it would kill it initially, but it will shorten it's life span.  I think they have a better one for like $5.  Not much info on it though.
http://www.radioshack.com/product/index.jsp?productId=2062480&cp

Really busy sorry can't help more.

[juggle50]

Hmmm,  I know nothing of diodes and barely understand relays.  I just did a little research.  Am I correct in saying that the purpose of the diode is to restrict the current to only one direction so current does not flow back into my ledwiz?

Is the purpose of the fuse so that the relay will not get blown?

I know it isn't anyone's job to hold my hand, but if you would be so kind as to reccomend a type of fuse and diode and maybe draw up a little circuit diagram for a moron.  I would greatly appreciate it.  This project got a little more out of my league than I first expected.

Let me know if the general consensus is that a relay would be too slow, if there are alternate routes to get the project to work with a ledwiz

Thank you again for all your help Poonga, 2600 & Level, I'm learning a lot.

[2600]

The purpose of the fuse is protect the knocker.  If the relay does get stuck or something then you want the fuse to blow before your knocker does.  Connect it just like a real Q*Bert does and use what everyone else does. 

The diode protects the relay itself from a short life and also other devices. Off the top of my head 1N4001 should be fine, I think.  The coil should have a diode as well just in case you want to check.

I don't think the speed of the relay will be your problem.

Don't have time to draw it up right now.  Try to draw it yourelf and myself and others can try to comment.  Don't forget to test the circuit without the knocker connected.

[juggle50]

Okay guys, how's this.  It's the same as poonga's with the addition of the diode and fuse.  However, I think by drawing it I've got a better understanding of how the relay works.  Correct me if I'm wrong, but doesn't the positive current just pass through the relay which completes the circuit electromagnetically when switched on by the led wiz?

Also, what device would I use to test the circuit without the knocker?  And finally, because my ledwiz is quite hard to easily access, can I hook up a 4.8 volt battery pack with a switch and manually turn on the circuit to simulate the led wiz in order to test everything?

Thanks again fellas.

[Level42]

Hey Juggle, yes in theory this should work. You don't need to actualy connect another device then the knocker to test the circuit, you should hear the relay clicking when triggered.

You can do the battery thing, but run it without the knocker attatched. OR don't use a switch, but very momentarely touch the plus side of the terminal of the battery with a wire to simulate the trigger pulse.

To 2600: yous comments seem correct to me. (Those are cunstructive comments ) Sorry for my harsh reply earlier. I wonder if we can two more resistors to devide the voltage so we can bring it down to a safe voltage for the Vbe.

Alternatively, something like a 7805 could work, but you can't put 30V directly into that....

[2600]

Woops forgot about this thread, been busy.

Juggle, the diode should be across the + and - that is in between the LEDWIZ and Relay.
The other part looks fine if I am reading your drawing correctly.


Level42, Datasheet says you can feed 35V into an LM7805, but regulating down to 5V it's going to get hot.  The question is do you need to isolate the power?  You are isolating the IPAC, do you need to isolate the power or protect it or none of the above?

[Level42]

Wrong again...sorry...

[juggle50]

Does that mean that I need two diodes?  One for the + and one for the - going from the ledwiz to the relay? 

Right now I'm playing around with lsq files and lwa files in powermame to isolate the ledwiz port so only the knocker fires and not everything else in when qbert falls off.

What is everyone else using for the fuse.  I'm going to buy all that stuff this week.

Thanks for your help guys.

[Level42]

Level42, Datasheet says you can feed 35V into an LM7805, but regulating down to 5V it's going to get hot.  The question is do you need to isolate the power?  You are isolating the IPAC, do you need to isolate the power or protect it or none of the above?

Yeah the 35V is an absolute maximum and normaly you would put max about 20V into a 7805. Not needed for isolating, just for lowering the Vbe voltage. However, in theory this can also be done with a simple voltage divider using resistors.

Forgive my persistance, but I want to see if I can learn a little from this too....here's my last attempt, 2600 please review and let me know what you think.

R3 (10k) and R4 (1k)  work as the voltage devider. There should be a little less then 3 Volts on Vbe this way. I've lowered R2 to 20k, since the base current will be already running through R3 which is 10k, so 10k+20k is 30k which should give a safe base current.

Although I don't see the need for it, R3 and R4 should also work as pull down resistors as you suggest.

Fire at will !!! If this is all wrong again, I'll stick to Brad's original design

[2600]

Does that mean that I need two diodes?  One for the + and one for the - going from the ledwiz to the relay? 

See here.

http://www.kpsec.freeuk.com/components/relay.htm

The diode goes across the +/-.

[2600]

Level42, Datasheet says you can feed 35V into an LM7805, but regulating down to 5V it's going to get hot.  The question is do you need to isolate the power?  You are isolating the IPAC, do you need to isolate the power or protect it or none of the above?

Yeah the 35V is an absolute maximum and normaly you would put max about 20V into a 7805. Not needed for isolating, just for lowering the Vbe voltage. However, in theory this can also be done with a simple voltage divider using resistors.

Forgive my persistance, but I want to see if I can learn a little from this too....here's my last attempt, 2600 please review and let me know what you think.

R3 (10k) and R4 (1k)  work as the voltage devider. There should be a little less then 3 Volts on Vbe this way. I've lowered R2 to 20k, since the base current will be already running through R3 which is 10k, so 10k+20k is 30k which should give a safe base current.

Although I don't see the need for it, R3 and R4 should also work as pull down resistors as you suggest.

Fire at will !!! If this is all wrong again, I'll stick to Brad's original design

Sorry, but no.  Your problem is trying to use a voltage divider.  That's why I asked my original question.  Do you have to use the 30V supply?  Do you require isolation from your other voltage supply, ie IPAC, PC?

But don't just listen to me, there are a lot of good people here.

[Level42]

Well basicaly, that is what introducing the optoisolator was all about. Using the power on the PC/Ledwiz/I-pac side would still couple that with the 30V and the idea was to make an electrical seperation between those.

So then the optoisolator is totaly unneccesary and complicating things and we could better use Brad's original diagram.

Still haven't received the knocker by the way ! 

[2600]

You can use an isolated DC-DC converter powered off the 5v line.

[juggle50]

Okay, I think I get it now.  The protection diode should look like the one on my  knocker right.  How is this new diagram.  Also, is this the right fuse

http://www.radioshack.com/product/index.jsp?productId=2102747&cp

This might sound really moronic but do you solder the fuse on there or do you get some type of fuse holder?

[Level42]

Yes the diode on the knocker is actualy performing the same function. A relay and a knocker both use coils and have more or less the same charcteristics.

That fuse is fine. Use this http://www.radioshack.com/product/index.jsp?productId=2102786&cp=&pg=4&origkw=fuseholder&kw=fuseholder&parentPage=search
fusholder. Fuses have the possibility to blow out (that's what they're for) and you want to easily replace it if that happens. Even if you get it soldered (probably not, the metal on those caps is probably very solder-unfriendly it would be very clumsy.

I don't think your diagram is fully correct I don't really understand your plus signs...I'll draw a new diagram tha should work in my next posting.

[Level42]

While drawing the diagram I was thinking of this:

Juggle, what relay are you gonna use ? You have to keep in mind the current drawn by the relay. The ledwizz is intended for supplying enough current for LEDs. Those use very little current (let's say 20 mA). The relay suggested by 2600 is using 90 mA f.i. It could be fine, but better be safe then sorry !

I checked the manual of the Ledwizz on GGG's site, but it doesn't say anything about how much current each port can deliver. There is a remark about the TOTAL current drawn though. Don't know if you also use your LEDwizz for driving lots of leds (probably, why else would you buy it) but if the total current is over 500 mA you must use seperate wiring for the +5 V (see the manual).

Check with RandyT of GGG how much current each port can deliver before proceeding.


Anyway, here's the diagram I made. Be aware that the knocker already has a diode on board. When you look at the diode there is a line at one side of the diode. This corresponds with the line of the symbol in the diagram. In this application (!) the wire of the diode that is closes to the line should be connected to the PLUS side.

It's so hard to explain through text only :S Hope you understand. It is essential to wire up the diodes correctly.

To confuse you even more: some relays already have a diode built-in. check with the supplier. However, it doesn't hurt to have two diodes....

[juggle50]

Thanks Level 42,

I think I understand your diagram.  Thank you for taking the time to do that.  I would like to learn how to read those better.  Am I right in saying that the negative wire from the power supply goes directly to the knocker and the positive passes through the relay so it can break/ complete the circuit?

That is a good question about the Ma's coming from the ledwiz.  I will PM Randy today.  I actually only have a few led's in my cab which is why I thought about this project origionally.  I wanted more out of my ledWiz.    

Unfortunately this project will move pretty slowly in the next few months as work starts picking up this week.  So I will be reporting progress rather slowly.

Thanks again Level

[Level42]

Hey Juggle, you're welcome !

Yes, you understand it correctly. So it's the plus of the 30V supply going to one side of the fuse (doesn't matter which side), the other side of the fuse (or better: fuseholder) is going to the common (C) contact of the relay. The NO (Normaly Open) contact of the relay is than wired to the plus side of the knocker (did you get what side of the diode that is ?). Then the other side of the knocker is wired straight to the - side of the 30V supply.

Well, it's going to be some time here as well, since some guy at tntamusements accidently sent my knocker by ship.........   Well at least they're honest enought to admit it AND they refunded me the difference in shipping costs right away, so I still believe tntamusements is a great company to deal with.

[juggle50]

I gotcha,

So the fuse is between the power supply and the relay on the positive, rather than between the relay and the knocker on the positive as it is in my diagram.  That is a big help.

I talked to Randy and the MA output is 500ma's total if you are using the power from the usb or 500ma's per port if you wire the power directly from the Computer Power supply to the LedWiz.  So that should work just fine. 

Also, I created a new qbert.lsq for powermame which will isolate the port outputing the 5 volts to the relay.  It wasn't too hard to figure out, just had to get more familiar with both powermame and LedWiz lsq files.

Oh yeah, does anybody know if the sound of the knocker that plays in MAME (or powermame) can be switched off?  I couldn't find away to do that.  Or would it play on the original game?I can't remember.

I'll order the relays, fuse, fuse holder and diode today. (probably several just in case I  I make a mistake.) 

Level, that sucks that yours got put on a boat.  If it never arrives let me know and I can order one for you from that Pinball supplier that I bought mine from.

Lastly, thanks for your help on telling me which way all the wires go to the relay.  I'll probably need some more help with that but I was going to wait to ask anything until I got all the parts.

Talk to you soon fellas

[Level42]

Sure thing, about the knocker sound, cant you simply delete the sample file ?

[Level42]

Finaly received my knocker !!!! It's exactly the right one.  I tested it with 2 12Volt batteries in series (so about 24 Volts). I've experimented a bit with it, and I'm convinced that this thing needs a box to sound as good as possible. Tried it on a side of my cab, but this doesn't give a low sound. I tried it on a small shoebox and it sounded amazingly good !

Anyone with a real Q*bert cab that can tell us how this is built into the original ?

[juggle50]

Hey Level,

I'm glad to hear that  your knocker finally came, that is awesome!!!!  My radio shack stuff came the other day as well although I'm so busy right now I don't know when I'll have time to experiment.    I haven't had a chance to play around with the artifical qbert sount in PowerMame.  PowerMame does not have a samples folder, which leads me to believe the sound is in the rom.  Again, I'll have to put more time into investigating.

As far as the box for the knocker, I don't know how the origional was set up, but have you tried mounting it  in one of the bottom cornors of your cab so that the rubber piece on the very bottom of the knocker is touching the bottom of the cab?  I saw a picture of it mounted that way in a cab, however the picture was of a mame machine not an origional qbert cab.  It may resinate more if it is mounted to the bottom..

Also, I've got the relay and am confident I have found the COM pin and the NO pin.  However, I'm a little confused about the + and -  pins that will be wired to the ledwiz.  It isn't clear which is supposed to be wired to the positive and which is supposed to be wired to the negative.  Does it matter as long as I have the diode going the right way?

Anyway, stoked that your stuff came.

[Level42]

Thx Juggle,

No the coil of the relay doesn't have a + or - side. It doesn't matter which way you connect it. (Unless there's a built-in diode, but that is normaly not the case). Are there any markings like C or something on the other pins ? Then those are the coil connections.

I will get my electronics stuff this week and will report back. Think I will first set it up like Brad has done it. If that will work, I still will see if my design has any chance on working. I will check with some electronics guys.