Hi steve,
I imported the circuit, deleted the input voltage and then inserted it again and the circuit worked!
Yeah, well maybe I'd have to do that for your version below, because it had the same problem when I loaded it. Fortunately, for simple circuits like this I don't need the simulator
So now we have 2 LEDs working with the switches, i have added the other green LED and 2 other red LEDs. The diode helps keep the second green led on as required when the first swith is activated.
That diode will simply prevent the second LED from ever turning on. In addition, the inverters have a limited drive, and will simply not be able to provide sufficient current for 2 LEDs. You may be able to get away with placing 2 red or green LEDs in series (bur not blue)
You also seem to have extraneous connections going off the right of the simulator screen.
So if this looks ok, and you are happy could we use the feed to the red LEDs to feed a 555 timer for the blue flashers or am i getting a bit ahead of myself.
You're getting a little ahead of yourself.
You can't use the same inverter that is being used to drive the LED as the output voltage will sag. You need to use another inverter to buffer the output of the bistable (remember you have 6 to a package, so there's plenty of them available).
In addition, because of the same output drive issue, you can't power a 555 from the logic output.
But that's OK because there are easier ways
Let's just skip ahead a bit though... Once you have the bistable figured out you can use a much simpler oscillator.
One like this:
$ 1 5.0E-6 0.23009758908928252 89 5.0 50
I 192 208 320 208 0 0.5
c 192 208 192 304 0 1.0E-5 1.5212852784843263
g 192 304 192 336 0
r 192 144 320 144 0 10000.0
w 320 144 320 208 0
w 192 144 192 208 0
w 320 208 384 208 0
This DOES NOT simulate correctly because the device shown is an inverter not a schmitt trigger, however it is a very simple oscillator that will suit your purposes nicely. Because of the simplicity, you can have multiple oscillators if you like, so the flashing of LEDs and the counter can be happening at different rates.
How we stop and start this oscillator is something we'll come back to later...
Perhaps we should consider how to turn the LEDs on and off. At the moment we've been using inverters, but they are not the greatest because they have very limited output current. What you need is something that can drive several LEDs.
$ 1 5.0E-6 0.23009758908928252 89 5.0 50
I 192 208 320 208 0 0.5
c 192 208 192 304 0 1.0E-5 1.5212852784843263
g 192 304 192 336 0
r 192 144 320 144 0 10000.0
w 320 144 320 208 0
w 192 144 192 208 0
w 320 208 384 208 0
That will do it. The resistor values are not appropriate, but it illustrates what happens. Click on the H/L to change the state.
I think we need to have an additional module:
1) bistable
2) LED driver(s)
3) oscillator(s)
4) counter
both the bistable and one of the oscillators will need a LED driver to turn on LEDs. The LED driver is capable of driving other things too, perhaps the flipper can be controlled by one of these (with some slight modifications)
So we can simplify the bistable to look more like this (without the LEDs)
$ 1 5.0E-6 0.12316236423470497 50 5.0 50
I 160 224 256 224 0 0.5
I 256 224 336 224 0 0.5
r 336 224 336 128 0 100000.0
w 336 128 160 128 0
w 160 128 160 224 0
w 0 64 112 64 0
r 112 80 112 128 0 4700.0
s 112 128 112 224 0 1 true
s 112 320 112 224 0 1 true
r 112 320 112 384 0 4700.0
g 112 384 112 400 0
w 160 224 112 224 0
w 112 64 112 80 0
I 336 224 416 224 0 0.5
I 336 272 416 272 0 0.5
w 336 224 336 272 0
R 0 64 0 0 0 0 40.0 5.0 0.0 0.0 0.5
w 416 272 416 224 0
w 416 224 448 224 0
I 256 272 320 272 0 0.5
I 256 320 320 320 0 0.5
w 256 224 256 272 0
w 256 272 256 320 0
w 320 272 320 320 0
w 320 320 448 320 0
M 464 224 480 224 0 2.5
M 464 320 480 320 0 2.5
w 448 224 464 224 0
w 448 320 464 320 0
Note that I have paralleled 2 gates for each of the outputs -- that increases their drive capabilities. The use of all 6 gates means this part of the circuit use exactly 1 package, so it is a little easier to construct. It may be a little wasteful of gates, but it means you can create a list of components and place them to one side.
Do you understand how it operates?
Do you think you can find the datasheet on a 40106 and work out how you'd wire this up?
