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  #41  
Old 04-21-2012, 03:52 PM
elec_mech elec_mech is offline
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Hi Chris,

Hmm, adding features after you've got everything working? You must have some engineer's blood in you then.

First, I must have missed this before, sorry, but disconnect pins 4-7 and 13-15 from each and from ground of the 4060. These are all outputs and don't need to be tied to ground (plus you'll need them now). You can leave pin 9 disconnected as well, but if the clock is accurate, don't worry about it.

When you say pull pin 15 high, do you mean just that? The only way to decrement the counter (as you stated, pin 10 is held low) that way is to send a clock signal to pin 15 (high-low-high-etc.). You could tie one of the remote outputs to pin 15, but since all clock pins are tied together, the user would have to repeatedly press up and down on the remote button and would decrement by seconds which would take forever.

What you want is a fast clock. Thankfully, your 4060 is dividing 32.768kHz down to 2Hz (then 1Hz through the 4027). This is done by dividing the crystal signal multiple times on pins 1-7, and 13-15 (take a quick look at 4060 pinout here: http://www.coolcircuit.com/circuit/t...060/index.html).

I assume you still have your breadboard setup? With the clock paused, preset the counter to 45:00. Now, take a long jumper wire and connect it to pin 15 of any 4510 (since they are all connected). Now touch the other end of the jumper on one of the following pins of the 4060: 1-7, 13-15. Experiment with all of these pins until you find the best "FAST ADVANCE" and "SLOW ADVANCE" setting (per your diagram).

Once you've determined this, you can put a NPN transistor or MOSFET between the appropriate 4060 pin and pin 15 of the 4510s, then connect the remote signal to the base/gate of the transistor/MOSFET. If you use a transistor, you'll need to add a base resistor - I'd suggest a MOSFET if you have it. Either will act as a switch to short the 4510 clock pin to the faster 4060 pins.

This will decrement seconds and all which might be a little bit of a pain to set back to 00 once you get the minutes value where you need it. If you're feeling ambitious, you could try either adding 10kΩ resistors between the 1Hz clock signal and each of the pin 15 of the 4510s - then jumper pin 15 of each of the 4510s controlling the minutes and tie directly to the faster 4060 pins. See if this only changes the minutes value and keeps the seconds at 00. Alternately, try adding a signal diode like 1N914 or 1N4148 in series to 1Hz signal between the 4510s controlling the minutes and the 4510s controlling the seconds. This might do it too. This added goal is to only allow the minutes to change and keep the seconds set at 00. You might come up with something better.

In a perfect world, you could make multiple BCD inputs to the presets of the minute 4510s then press the corresponding remote button for 20:00 minutes and have just the 20 preset energized so the 20 is loaded into the minutes value. This would require a short time delay so that when the 20 minute remote button was pressed, the 20 BCD value was energized, the others were off, and then the preset was enabled. Number of other ways to do this, but it would require some thinking through and more parts. Using the faster clock outputs of the 4060 will do what you want with minimal effort and parts.

Great job on the circuit, loved the mention you got on the soccer website. I'm very glad to be able to help you out, then to see the fruits of your labor, simply awesome! Great job and good luck!
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  #42  
Old 04-21-2012, 11:47 PM
chrischrischris chrischrischris is offline
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Thanks elec_mech.
Yes, still working on the breadboard.
I was thinking of using the clock output as well - just didn't know how. Yes the trick is to only do the minutes and hold the seconds at 00. I'll try your suggestions today. Thanks also for the correction to 4-7 and 13-15. My bad assumption.
This morning however, I was wondering if it would be better and cleaner to include 3 BCD inputs to the 10s 4510 (to change to either 4, 3, 2) and 2 BCD inputs to the 1s 4510 (to get 5 or 0) - hence 45, 40, 35, 30, 25 or 20.. However if I did, I was pondering on how I could "toggle" these to trigger one after the other with the same remote button. It would have to input to an IC that would turn on these combinations one after the other. Would this be easy'sh?

I just though again - I have a 12 channel remote. Functions to date are:
1 = Home score "up"
2 = Away score "up"
3 = Home score "reset"
4 = Away score "reset"
5 = Timer "pause/resume"
6 = Nil
7 = Nil
8 = Nil
9 = Clock "fast advance" (a real time clock - seperate circuit - adopted from "Doctronics" website)
10 = Clock "slow advance"
11 = Enable to power to reset counter and clock (safety)
12 = Timer "reset to 45:00" as well as "pause"

What if remote button 6 = preset "3" for the tens, remote button 7 = preset to "2" for the tens and remote button 8 = preset "0" for the ones? That would give me all 6 times I need (45, 40, 35, 30, 25 and 20). Would it be possible to run these independantly?

Last edited by chrischrischris; 04-21-2012 at 11:56 PM.
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  #43  
Old 04-22-2012, 12:52 AM
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Bill_Marsden Bill_Marsden is offline
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I am looking at your schematics trying to figure out how you set the times. You conventions are a bit odd, not surprising since you have had no formal training, it does make things a bit hard to read for a set in his ways crusty type like me, but I will persevere. I may even redraw them if you'd like, I am pretty impressed overall. This is a project well worth documenting. Over all it is much more advanced than the Stadium circuit I designed for combat robotics (and never built).

So before I jump in half cocked how do you set them manually at this moment? This will likely dictate how to set them remotely, the mechanism would be the same. You mainly need to work on the count down timer, the quarter counter, and the clock and the score keeping counters, did I miss anything? Please point me to any posts with a schematic I need to refer to.

The OP asked me for my input, and I have got to get up to speed. The first thing is to establish the local controls, they drive what the remote controls look like.

If you want to work on the remote separately mean while, try setting something up where you can light 1 or more of the 12 LEDs with a control panel, this can be adapted later with ease once it is working.

Elec Mech is much further along on this circuit, and you and he have a good working relationship (which is more important than it looks). I have no intention of taking over, just offering another set of eyes that might help.

Edit: additional info. If you wanted specific remote features you need to design them into the manual set controls. I suspect you have locked yourself in on some things, and probably don't want to take the time (and extra components) to do a major redo. Could be wrong, but that is my interpretation.
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Last edited by Bill_Marsden; 04-22-2012 at 01:06 AM.
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  #44  
Old 04-22-2012, 03:12 AM
chrischrischris chrischrischris is offline
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Hi Bill.

I've attached the current drawing (which includes wiring diagram and prelim. PCB layouts). Most PCB layouts are 2 sided - hence they look a bit confusing.

Count down timer PCB_V5.pdf

I made a couple of corrections this morning as suggested by elec_mech.
As for the remote control, I bought a 12 channel unit on ebay for around $10. I've got 9 out of the 12 channels currently hooked up to my breadboard (as outlined above in this thread). They work a treat.

As you can see in the pdf, there are four parts:
  1. Home and Away score - done - working on the breadboard
  2. Re-settable count-down clock - this is the only big issue now
  3. Normal clock (from "doctronics site") - working on the breadboard (hence I've only drawn up the PCB layout in my AutoCAD / PDF file)
  4. Temperature display - no problems - working on the breadboard
The way the count down timer works at the moment:
  • I press remote button "11" and it latches power for 30 seconds only to allow me to change the clock time (item "3" above) as well as allows me to reset the timer (item "2" above). I thought this would be a good safety in case during a match someone accidentally presses button 12 that resets the count down clock, or stuffs up the real time clock time during the day.
  • As note above, I press remote "12" and it resets the clock and pauses it at the same time (else it would reset then start counting down straight away before the ref blew his whistle to start the game)
  • The reset noted above make pins 9 momentarily high in the 4510s of the "second displays" to reset them to 00. At the same time, it makes pins 1 momentarily high in the 4510s of the "minute displays" (i.e. to load preset input). This loads input from the 2 lots of 4pin dip switches in the circuit. These I've set to 4 and 5 respetively to get the 45 minutes (i.e. 0010 and 1010). However the way they are being pulled high or low (not sure which), I had to reverse them (i.e. 1101 and 0101). Showing my limited knowledge here again!
I've just tried elec_mech's suggestion of trying to using the clock to fast and slow advance the minutes independantly of the seconds and it sort of worked but have had some problems with miss counting or flickering of the minutes displays. Also, it's not as professional as going straight to the correct time in one or a few presses.

My preferance if possible, as elec_mech also suggested is to include some more preset dip switchs to also run 40, 35, 30, 25 and 20. In theory I think this could work in the manner that I just asked elec_mech:

What if remote button 6 = preset "3" for the tens, remote button 7 = preset to "2" for the tens and remote button 8 = preset "0" for the ones? That would give me all 6 times I need (45, 40, 35, 30, 25 and 20). Would it be possible to run these independantly?

Alternatively, and maybe even better, I could include 6 presets in the circuit ( each containing 8 dips switches) to run the different combinations on the 4510s minutes. These could be triggered by one single button on the remote. If that button triggers the clock in a new 4017, each press could initiate a different preset until arriving at the desired preset time. Your thoughts?
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  #45  
Old 04-22-2012, 03:16 AM
elec_mech elec_mech is offline
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Hey Chris,

Okay, I've been pondering this and I think I have a couple of solutions. It really breaks down to the user interface and how much you want to do.

One way is to add another 4510 to each of the existing minute 4510s and dedicate remote output 6 for the tens and output 7 for the ones to control the clock. Thus, the user would hold down button 12, then press buttons 6 and 7, one at a time, to scroll through 0-9 for each place (tens and ones). This adds more parts and a bigger board.

You can do what you are describing, specifically using buttons 6-8 on the remote to give you a few different combos. To do this, you want something that changes the state of 2-3 pins of the preset inputs with a single signal from the remote. I don't think this can be done with one button press, but we can swing it with two. For example, the user decides they want the minutes to read 25. They'd hold down button 7 on the remote then press button 12. To get 30 minutes, the user would hold down buttons 6 and 8 then press button 12. Bare with me, I'm working this out backwards.

Would this be okay? The simplest way I can think to do this with the least number of parts and space is to add a few more BCD switches, technically one since you already have two. The remote outputs would then feed the 12V input into each of the BCD switches to get the right value. In this case, you'd hard-wire 45 (4 for the tens, 5 for the ones) but use 10kΩ resistors to connect each D/C/B/A input to GND or Vcc, respectfully. You'll then need two BCD switches for the tens (for 2 and 3) and one for the ones (for 0).

Think about this and let me know what you think. I'd go into more depth, but I gotta get to bed.
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  #46  
Old 04-22-2012, 12:06 PM
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Bill_Marsden Bill_Marsden is offline
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OK, I have found the section you have planned on using for the control.

I would put manual controls on the stadium circuits as well as the remote, for testing if nothing else (it will come in useful).

My question is what is it not doing that you need it to do? What are you trying to fix?



A comment about schematics. It is probably too late at this stage, but you should always get parts a number such as Q1 and U3 (etc), so you can identify specific parts of a schematic. Makes talking about a design with another person a nightmare otherwise.
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  #47  
Old 04-22-2012, 01:35 PM
chrischrischris chrischrischris is offline
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Hi Bill & elec_mech.
Problem fixed.

Preset Schematic:
Count down Presets only schematic.pdf

Count down circuit total:
Count down circuit total.pdf


I was trying to somehow make it quick and easy way to set to 45:00, or 40:00, or 35, 30, 25 or 20:00. I've been working on the circuit all day now and "finally" resolved it with elec_mech's suggestion of adding more BCD presets and the use of a 4017 to toggle each.

I needed to reset the tens to either 2, 3, or 4 (0100, 1100 or 0010) and the ones to 5 or 0 (1010 or 0000).

After drawing the circuit, I found that a dozen diodes would do the trick (along with a 4017). Never used a 4017 before - it's excellent. It can toggle up to 10 outputs by repeated pressing of my remote. Linking the 7th output to reset makes it toggle 6 output then repeat. I used these 6 outputs to both power up the preset combination, reset and pause the clock with a single press. Pressing a second time, flips to the next preset time, then the next and next. Works perfectly.

Thanks guys. This week the large digits should arrive so I can test them with my breadboard. Then I just need to tackle the higher voltage for these digits. Then time to build !!! I'll keep in touch.
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  #48  
Old 04-28-2012, 11:07 AM
chrischrischris chrischrischris is offline
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Default Power to led displays

Elec_mech,

A couple of questions if I may...

The 6", 8" and 10" seven segment led displays arrived. But they've raised a few questions. From the spec sheets, these need a forward V per seg of:

6" = 23.1 to 26.6 (because of 7 leds = I think 3.3V to 3.8V)
8" = 23.1 to 26.6 (with 7 leds, 3.3V - 3.8V)
10" = 33.0 to 38 (with 10 leds 3.3V - 3.8V)

Refer attached spec sheets
NFD-60011BUx-01.pdf
NFD-80011BUx-01.pdf
NFD-100011BUx-01.pdf

As an example, one of the 6" segments is made up of 2 leds in parallel time 7 sets in series. Per segment, the forward current seems to be 60mA (6"), 150mA (8") and 120mA(10"). Given I have 6 x 6" displays, 4 of the 8" and 4 of the 10" the total if correct is 6x60x7(2.52A) + 4x150x7(4.2A) + 4x120 x 7(3.36A).

I assume I therefore need a 24V DC regulated power supply that can deliver 2.52+4.2 = about 7Amps (maybe a 10 amp unit). Would this unit work:
http://www.austeknis.com/product.det...?pid=AT-PS2410 , or http://www.ebay.com.au/itm/24V-10A-D...ht_2153wt_1062


As for the 33 volt supply - I need around 5amp. Where the heck do I get this unit?. Should I build it?

Also, I started testing the 8" display. To get the same "current" in every segment, I had to use 22Ω resistors on 4 segments and 39Ω on the other 3. Is this normal or have I bought faulty displays?

Also, I find the current creeps up and stabilizes after the segment are warm - is this normal?

Lastly, the resistors get hot (especially the 33Ω ones). I'm using 1/4W which are obviously too small. How do I calculate the correct wattage (for power dissipation)? Sorry for the zillion questions and thanks for your patience.
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  #49  
Old 04-28-2012, 11:12 AM
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There are other ways to handle hot resistors. Use two or three resistors in parallel, for example, or even in series. This will spread the heat around.

A clock project I build over a decade ago had a similar problem. Since this was a kit I was pretty surprised. The resistors got hot enough to melt solder on the board, which I thought was kind of rude.

I have several 24VDC 6.5A supplies I have kicking around, they are pretty common. How hard core are you on the 33 volts?

I would not build it myself, you could always use two modules to create the needed voltage, say 24VDC and 9VDC at 6 amps or more, preferably more amps. When using a component such as a power supply add extra to the specs, they will last much longer. Many of us use the 50%, but with power supplies the extra cost is such that may not be practical, but add some head room on the current if you can.

The power supplies you showed are pretty similar to the units I was thinking about.
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Last edited by Bill_Marsden; 04-28-2012 at 11:18 AM.
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  #50  
Old 04-28-2012, 12:34 PM
chrischrischris chrischrischris is offline
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Hi Bill.
Thanks for the reply.
I could you a couple of resistors, but I assumed due to the current going through them, the 1/4w are undersize. Since I have to buy the correct ohm resistors, will larger ones (1/2w or 1w) do the same job?

As for power supplies, I asked someone in the electronic store today and he said something about not being able to join two power supplies due to "switching" or something, so I abandoned the idea.

So can I just join the leads in series (24V and 9V supply) without any issue? If so, that would be fantastic. As for the amps, yes I agree. If I need 5amps I'd rather get 10amps - doesn't cost much extra.
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