Upper Console DPDT Latching Rockers DTMF Tone Request

Here is a little something we are working on to add a little more flash to the Upper Console. The momentary switches are simple enough to have request a random DTMF tone from the Voice Box, but for latching switches this is a lot more complicated. So what we have here is a circuit scenario that makes use of a few simple components to achieve just that. This scenario makes use of the 555 timer IC chip to send a short one second pulse to the Voice Box's DTMF tone generator which is roughly about the same as a momentary button. In this diagram I have 2 mapped out for simplicity but essentially you would continue the pattern for each DPDT Rocker Switch. The LED indicator lights board is optional but I like it. On the indicator board I have green LEDs and red LEDs that would each light up for about a second when each corresponding Rocker Switch has been turned on, also a short signal is sent to the Voice Box to request the random DTMF tone.

IMPORTANT NOTE:

There are a few errors in the 555 Timer circuit above, also this new one has been simplified a little eliminating one Capacitor and swapping out a Resistor for a Variable resistor. Out side of that just swap out the Piezo Buzzer for your LED connection. :)

 

DTMF Tone Request Experimentations

In making sure that I well isolate the Voice Box's DTMF tone request from any momentary buttons I have I figured I would rig up a mini Songo 12V Relay very close to the Voce Box. Now what happens here is that when a DTMF Tone request is called by any momentary button I have hooked up to a wire that I am calling "DTMF Tone Request" THAT wire goes to the magnetic coil of this mini Songo 12V Relay's Ground (-), the other side of the magnetic coil goes to 12V (+). So this then trips the Relay's internal isolated switch which I then have connected to both the Voice Box's Ground (-) and also the DTMF Tone Request port. You will have to excuse my somewhat over sized piece of PCB board it was all I had kicking around that I could use to mount this small relay onto and connect wires too. I'll most likely change it later when I get some smaller pieces of PCB Proto-Board. The wires from the Switch Pods that request the DTMF tone I just have going directly into the Voice Box's DTMF Tone request port.

Now the other part of today's fun was to wire up my Relays board for some experimentation just to make sure that I am understanding correctly just what is going on with this thing and how it interacts with my buttons. All of this stuff gets pretty complicated if you are new to electronics like me. ;) My latest video that I posted to my blog explains best and visually how I have it all hooked up. But basically the Ground pulse buttons from my Space Matt buttons go into the ports on the board that connect to the Diodes, they connect to the DTMF Tone Request wire and also to the individual relays on the board. Each relays gets it's own ground pulse from each of the Space Matt buttons activating the Relays internal switch which I can hook up to any device I want to activate, in my case 5 of the Space Matt buttons are simply activating buttons that control the setting for my LCD screen. Although I have not yet hooked it up, a 6th button will cycle the Message Centre while producing a DTMF tone with each press of the button. The rest of the Space Matt buttons I don't have plans for just yet.

My Voice Projection unit activation button is wired up the same way as the Dash Power Button and makes a connection to ground to activate the Step Relay, this one was a little more tricky. You can see in the image above (middle left) that branching off from the wire that comes from the Normally Open terminal of the V.P. power button that I have placed a Diode in-line connecting to the DTMF Tone Request block.... which I moved onto the back of my Relays Board. Without the Diode in place the Space Matt buttons would activate the Step Relay for the Voice Projection unit as well, not good, so the Diode sure takes care of that as it only allows current to travel in one direction... taking me a while to get the hang of that but it works and it's cool... gotta love electronics ;)

So now with all of this in place I'll have to test it out on the Voice Box once the replacement I.C. Chip 01 comes in the mail. If everything works out well, and so far I can't see what not as a Relay does what a Relay does ;) But as I say if all goes well I can look into experimenting with the Optocouplers when they arrive and see if I can make a set up like this that takes up a lot less space. This would be fine if I only wanted to use a small amount of my Space Matt buttons but I can see eventually wanting to use more down the road as I trick out K.I.T.T. with more cool gadgets ;)   

DTMF Tone Generator Terminal Block

I made a simple terminal block for connection to my Voice Box's random DTMF tone generator. The tone generator needs a simple ground pulse from any momentary button that I want to generate a tone which means lots of connections so I whipped this up. I had a piece of fairly thick brass from some electronics scrap I had kicking around. I drilled in some holes and screwed it onto a piece of Lexan plastic to serve as a mounting bed that I can then later screw onto the stock OEM plastic dash under my Knight Rider dash. Using my relay boards I can already get a fair amount of connections through just one wire so this gives me more to eventually connect to should I ever need too.

Later Today Update

I installed the terminal block under the stock OEM dash for the DTMF V.B. tone generator as you can see in these two pictures here (right & left). I have the entire block connected to a connector that connects to the other end of the plug under the Knight Rider dash. This should give me lots of connections for any buttons I want to generate a tone using the Voice Box's built in DTMF tone generator.

Just Realized!

I just realized that I can wire up my Voice Projection Unit's power button to my V.B. Random DTMF tone generator as it's a ground connection button that goes to a Step Relay mounted in under my OEM dash (Top left image, Step Relay on the far left). All I need to do is tap into the black wire just before it goes into the Step Relay and attach it to my DTMF terminal block, that should give me a random tone generated through the V.B. when the system is switched on and off. Something to experiment with today for sure. ;)

Don't do it Michael!

Well apparently the V.B. did not like that plan very well and I think I fried the V.B's Random tone request option because now the V.B. only plays the tones during the start up sequence. The tones work for the buttons in the PANP group but the input for random DTMF request is "Bitched!" :( Either is going to need a new chip or a new V.B.

I.C. Chip Needs Replacing

So I contacted the fine folks at Ideegeniali who make the Knight Rider Voice Boxes, as it turns out it's just the I.C. 1 chip that I ended up burning out the digital inputs. Fortunately it's only going to cost me 10 Euros to replace the chip..... ah this is the kind of thing that happens when you are inexperienced like me with electronics, I'm just surprised it hasn't happened sooner with all of my crazy experimenting. ;)

Further Circuit Isolation Needed

I protecting the Voice Boxes DTMF tone request wire more I figure I'll isolate the two by doing something like this in my reworked diagram, only in place of the mini Songo 12V Relay I'll use an Optocoupler instead. That should isolate the Voice Boxes random DTMF tone request well enough from the rest of the circuit.

This Will Do The Trick

After some experimentation and some very expert advice from Paolo of Ideegeniali this new wiring scenario (left), for isolating the Voice Box's DTMF tone request seems to work very well as the small Songo Relay simply connects the Voice Box ground (-) to the DTMF tone request through it's internal switch. This makes for a very well isolated circuit so there is no chance of me accidentally overloading the I.C. 1 chip anymore.

Here you can see how I have added the small blue 12V Songo Relay onto the back of a piece of circuit board I had kicking around (right), it's a bit big I know but I needed to mount the tiny contacts of the relay onto something as they were too small for my Alligator clip test leads to grip onto. I may swap it out for a much smaller piece of PCB board later on depending on how much space it takes up under my dash otherwise "If It ain't broke, don't fix it." We'll see ;)

I have tested out my Tone requests from my buttons and relay board and they send the needed ground pulse to activate the coil in this mini Relay so that is perfect and just what we want. :)