Electronic Dart Scoreboard...

Grayhill - 96AB2-102-R - Allied Electronics keypad, non backlight

Jameco Electronics Opto & Illumination: JAMECO VALUEPRO: UN4043-13 EWRS-R 3 digit last score entered

LED's/LCD's - LED Display - 7FR5641BS 4 Digit Current score large display

That's what I've got so far that looks good, not exactly what I wanted but I think they would work.

I've been trying to find a good led for the cricket scoring. I think 5mm leds are too small. I'm trying to find some that houses the led and provides a clear cover lense so as to make it bigger. I'm thinking something like 8-10mm is big enough.

There are no 3.5 or 4 segment displays. What you are referring to are 7 segment displays with 3.5 or 4 digits. The segments are the little pieces (i.e. segments) that you turn on or off on the display to form different numbers different numbers. Each segment is designated by a letter a - g starting at the top and working around clockwise. The number 1 has segments b and c truned on, the number 2 has segments a,b,g,e, and d turned on and so on. I recommend that you read this article as you will ultimately need to understand how the display works for your project.

Seven-segment display - Wikipedia, the free encyclopedia

A display with 3.5 digits would have 3 digits containing all 7 segments and one digit with only a few segments. The first 3 digits can display any number 0 - 9 while the 4th can only display the number "1". So a 3.5 digit display can display any number 0 - 1999. The 4 digit display has 4 seven segment digits so it can display any number 0 - 9999.

That being said, you don't need to buy 3 or 4 digit displays. You can buy single digit displays and stack them end to end. As far as where to buy the display from, a quick google search for "blue LED 7 segment display" yielded a bunch of results. Here's one:

7 Segment Blue LED - Single 1.0 Inch (25.40mm) Anode LCS-10012TB11

I also searched ebay:

blue 7 segment, great deals on Business Industrial, Musical Instruments on eBay!


You might be able to find bigger and/or cheaper diaplays if you look around and look at different colors. The links above were just a few of the first hits I came up with.

If I was looking, I would try ebay, mouser.com, digikey.com, newark.com, or my local electronics store. With living in northern NJ I'm sure there is a surplus electronics component store somewhere. I would recommend finding it as you will porbably become a frequent customer as the project progresses. Ordering everything online can sometimes be a pain.

crudeau said:

Grayhill - 96AB2-102-R - Allied Electronics keypad, non backlight

Jameco Electronics Opto & Illumination: JAMECO VALUEPRO: UN4043-13 EWRS-R 3 digit last score entered

LED's/LCD's - LED Display - 7FR5641BS 4 Digit Current score large display

That's what I've got so far that looks good, not exactly what I wanted but I think they would work.

I've been trying to find a good led for the cricket scoring. I think 5mm leds are too small. I'm trying to find some that houses the led and provides a clear cover lense so as to make it bigger. I'm thinking something like 8-10mm is big enough.

Click to expand...

The keypad looks OK. Just make sure that you study the manufacturer's data sheet and that the manufacturer's part # for the item matches up with one of the keypads hat has only 7 pins.

The 7 segment displays that you chose won't work. The SAA1064 driver ICs that we will be using multiplex the digits in pairs 1,3 and 2,4. The display you have linked here would need the digits to be multiplexed indivdually. You should stick with single digit displays. Besides, you said you wanted 1" digits or larger. None of the links you showed were that big. One of them was even smaller than .5".

For the cricket LEDs, 10mm are widely availble. You can buy bags of brand new LEDs from China off of ebay for pretty cheap.

10 mm LED, great deals on Business Industrial, eBay Motors on eBay!

How are you planning to assemble the final product. I'm not talking about the case but the electronics. You will most likely have to fabricate a circuit board. Do you know how to do that or are you at least wiling to learn? You could also use perfboard but that could be a cluster.

i ment to say that i couldn't find any 7 segment displays that are 3.5 or 4 digits. I will look in the morning and find some better options for the displays now that I know they can be single.

On the Leds, I think that just a 10mm led is kind of blah looking. But maybe a 10mm led with a flat top would look alright.

The Keypad is in fact the 7 pin, I think they all are on that diagram, but some have backlights so they have more pins, but I want the unlit one.

As far as the circuit board, I think I would want to see what I have and go from there once all the parts are in front of me. I have never made one before, but I know that are kits that let you etch your own boards and stuff. I am willing to learn anything that you will teach me.

Once again, thank you for all the time and effort you are putting out there for me. I really appreciate it and hope that you have an excellent holiday season.

crudeau said:

On the Leds, I think that just a 10mm led is kind of blah looking. But maybe a 10mm led with a flat top would look alright.

Click to expand...

I know that they make square LEDs with a flat tops but I don't ever remember seeing a round LED with one. You could always grind it down with a dremel or something or you could use something like this:

**broken link removed**

I'll be traveling to NYC the 23rd - 29th of this month so not sure how often I'll be able to post. If you make sure to pick out the displays and keypad before then, I can work probably work on the code a little bit during my trip. You have a good holiday too.

me too!...with Arduino

Hey Guys. I'm looking to make a similar clone of the Dart Master 3 and this forum turned up during my search... I was also happy to see it's actually a current thread too!

So I have an EE degree but haven't done any HW/SW design in years. I thought this would be a nice project to re-learn some things while saving a bunch of money on an overpriced dart scoring system. I have an Arduino Mega (Arduino - ArduinoBoardMega) and plan to use that instead of a PIC for my micro controller. I took a look at your preliminary schematic and it looks very good. definitely helped me remember a few things, much more still to remember though. anyways. thanks for the work so far. I wonder if you have any experience with Arduino (It's actually my 1st project with the micro). I have a few questions if so, mainly SW related since im not too strong in that realm.

Also I'd love some help on the manufacturing side for a case, etc. I hope you guys are still into this project. Thanks.

dbrez8 said:

Hey Guys. I'm looking to make a similar clone of the Dart Master 3 and this forum turned up during my search... I was also happy to see it's actually a current thread too!

So I have an EE degree but haven't done any HW/SW design in years. I thought this would be a nice project to re-learn some things while saving a bunch of money on an overpriced dart scoring system. I have an Arduino Mega (Arduino - ArduinoBoardMega) and plan to use that instead of a PIC for my micro controller. I took a look at your preliminary schematic and it looks very good. definitely helped me remember a few things, much more still to remember though. anyways. thanks for the work so far. I wonder if you have any experience with Arduino (It's actually my 1st project with the micro). I have a few questions if so, mainly SW related since im not too strong in that realm.

Also I'd love some help on the manufacturing side for a case, etc. I hope you guys are still into this project. Thanks.

Click to expand...

Hi dbrez8 and welcome. I'd say that this thread is only quasi-current. The OP was supposed to select his components so that I could modify the design for his specific parts but that was over a month ago. I'm guessing he might have lost interest. I'd be happy to continue working on the project with you though. From the software side, I'm not sure how much help I can be because I've never worked with an Arduino before. I think it uses a proprietary programming language like the Stamp but I could be wrong. I work mostly in C and assembly and have only played with PICs before. There is also a Micro Controller forum here that you might find helpful. That aside, myself and others can offer input on circuit design and PCB layout when you get to that stage.

Thanks for your reply, vne147.

So i've used your reference schematic and have a preliminary BOM set up. Ill attach it once i am home. It contains the major components, but not the small diodes/resistors quite yet. I need to do some figuring given my exact 7-seg and LEDs specs. maybe you can help? ill send it along later anyways..

one main question I had was whether i would need the 7-seg driver IC's or if i could simply use Arduino digital I/O instead. I need to see if i have enough pins available. probably it will be easier to just use the ICs. Also i plan to have one more 7-seg (x3) display than the OP (6pcs 3x7 seg total). i think i can run this from the extra outputs available from the three IC's, right? for each IC i see that it can control one more 7-seg. this leaves 4 more and I only need another three. should be ok i guess, just not sure how ill drive that in SW yet...

I need to get xilinx back up and installed on my PC too.

lots of work to do. All of your help is much appreciated..

also regarding arduino programming...

A language reference sheet: Arduino - Extended Reference

says "The Arduino language is based on C/C++ and supports all standard C constructs and some C++ features. It links against AVR Libc and allows the use of any of its functions; see its user manual for details."

so i think it is similar to C, though I do not know too much about programming in general.

dbrez8 said:

one main question I had was whether i would need the 7-seg driver IC's or if i could simply use Arduino digital I/O instead.

Click to expand...

I don't know if I can say you need the ICs but you will make your life complicated without them for sure. The reason I chose those ICs was since they are I2C they only require 2 pins. You can control up to 16 7-segment digits with only 2 I/O pins on the MCU. You'll be hard pressed to find a significantly more efficient way to drive that many digits with that few pins in my opinion.

dbrez8 said:

Also i plan to have one more 7-seg (x3) display than the OP (6pcs 3x7 seg total). i think i can run this from the extra outputs available from the three IC's, right? for each IC i see that it can control one more 7-seg. this leaves 4 more and I only need another three.

Click to expand...

I don't see anything fundamentally wrong with this idea. It should be just a matter of programming. If for some reason this idea doesn't work however, you cannot just add another IC without additional mods becasue they have a 2 bit address so the maximum number that can be individually adressed on a single I2C bus is 2² = 4.

Yea i agree with you on the 7seg driver IC's, and at $1.5 each they are probably more than worth the time i'd have to put in otherwise..

heres my BOM
**broken link removed**

It has all the major components i think. It's missing the component resistors, diodes, and transistors. What do you think?

Like you mentioned, the transistors, diodes, and resistors are not there. Neither are the caps or the cricket pushbuttons. Also, it looks like you only have 3 SAA1064s but 4 are needed for the design.

I didn't take the time to go through the data sheets for all your LED displays but just make sure that the 3 digit displays have one common anode per digit. If there is only one common anode per 3 digit display, it won't work with the SAA1064.

Edit: Also, something for you to consider is that it looks like you are only ordering the exact number of components you'll need. I usually order extras. If you fry anything, you'll have extra on hand, if not you'll have spare for future projects. Just a thought.

Like you mentioned, the transistors, diodes, and resistors are not there. Neither are the caps or the cricket pushbuttons. Also, it looks like you only have 3 SAA1064s but 4 are needed for the design.

Click to expand...

You're right on the components. 4 IC's as well.

I didn't take the time to go through the data sheets for all your LED displays but just make sure that the 3 digit displays have one common anode per digit. If there is only one common anode per 3 digit display, it won't work with the SAA1064.

Click to expand...

hmm. here is the datasheet: 7 Segment Three Digit Red 0.56 Inch (14.2mm) LED Display Specs, Data Sheet LCT-5632TUR11 from lc-led.com
i think it has an anode per 7seg (as required) but all three have common pins for the segments.. is this ok? or maybe ill have to use a 2x 7seg due to the multiplexed driver IC? what do you think?

Edit: Also, something for you to consider is that it looks like you are only ordering the exact number of components you'll need. I usually order extras. If you fry anything, you'll have extra on hand, if not you'll have spare for future projects. Just a thought.

Click to expand...

Ha yes. i was only the BOM for min quantity i guess. I do plan on ordering some extras for when i make a mistake and let the 'magic smoke' out.

dbrez8 said:

hmm. here is the datasheet: 7 Segment Three Digit Red 0.56 Inch (14.2mm) LED Display Specs, Data Sheet LCT-5632TUR11 from lc-led.com
i think it has an anode per 7seg (as required) but all three have common pins for the segments.. is this ok? or maybe ill have to use a 2x 7seg due to the multiplexed driver IC? what do you think?

Click to expand...

That display won't work with the driver IC. Each pair needs to have it's own cathodes because of the way the driver IC multiplexes the digits. You should try to find a 2 digit display with shared cathodes and one anode per digit or just go with single digit common anode displays. That's probably what I'd go for. Most are end stackable and will look almost the same in the finished product.

vne147 said:

That display won't work with the driver IC. Each pair needs to have it's own cathodes because of the way the driver IC multiplexes the digits. You should try to find a 2 digit display with shared cathodes and one anode per digit or just go with single digit common anode displays. That's probably what I'd go for. Most are end stackable and will look almost the same in the finished product.

Click to expand...

OK I was afraid of that. I'll look for some new displays and update my BOM. stay tuned..

I haven't forgotten about it. I'm still slowly in the process of trying to figure out what to order. I'm actually having a hard time. When I come up with a completed list of components I will send it over to you to make sure it all works. Sorry it's been taking me so long.

Ha, me too!

Sorry for my absence here as well. I just moved to a new job and had to turn in my laptop. I have a new one coming tomorrow so I should be ready to pick this back up in the coming week or two once I'm back up and running.

OK, I'm interested too

Will this design be divulged in all its glory?

I don't have time to contribute sweat equity for weeks to come, but I'd like to build one of these things myself. Found the thread googling for such a thing.

Sweet work.

Yes. This is my plan anyways. To publish all the necessary info to DIY, and possibly offer pre-built ones if time permits.

That is, if @crudeau is still willing to help and I get off my a$$ and get a move on. I'll get back on track this weekend. promise

vne147 said:

Here is a prelimenary schematic. It probably needs some tweaking and there might be a few errors but it's good enough for you to start looking over and learning how the circuit will work. Ask questions if you don't understand something.

Click to expand...

Hey vne147, are you still interested in helping with this project? I hope so..

So i took a look at your schematic. I have a the 'Game Select' and '7 seg display' wiring are clear so far, but i have a question about the cricket LEDs (boxed in red in the pic). It looks like your using a bus to control all of the LEDs, and a control transistor (Q9 for the '15' block) to activate the separate numbers such as 15, 16, 17, etc. Its not clear to me how the following scenario would work..
15 has 1 LED on, 16 has 2 LEDs on... is this possible? it looks to me that it is not given the bus and control, or perhaps i'm not totally getting it. please help if you can or let me know if you need a better explaination.

Also would it be possible for you to send the native Schematic files over so i can play around with it?

Thanks!
-Dave