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Electronics 7-segment LED Clock

Discussion in 'Modding' started by Explicit, 27 Sep 2004.

  1. eutronix

    eutronix What's a Dremel?

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    Hi Chris,

    Thanks for the info on the LDRs and thanks for asking about our clock. It is going pretty well. We are still in the process of developing the decoding routine for the radio. We are starting with WWVB and a dedicated WWVB receiver, but hope to get the C-MAX CME8000 working on the other time servers as well soon. The menu for the clock is pretty much worked out. The 14 segment displays can scroll text messages of our choosing and the 7 segment displays display time all driven by a Maxim MAX6954 IC.

    Stuart
     
  2. SteveyG

    SteveyG Electromodder

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    I modded it so the backlight stayed on all the time powered by the AC adaptor. Didn't like having to press the button to light up the display :)
     
  3. tomjediknightt

    tomjediknightt What's a Dremel?

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    KOOL

    I was laughing so hard about your 5000 LED comment, good one. While I am designing a clock using discrete LED;s it isnt 5000, but ~4320. I am using 14V LED so I can use a 12v power supply. My PCB design is 5.5W x 8.5H in a 7-segment configuration.
    I love your matrix display. Do you sell those? I would liek to talk to you. You seem to know how to make display on a matrix. I have a kool project to ask about, maybe we can join forces?
    -tom
     
  4. tomjediknightt

    tomjediknightt What's a Dremel?

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    Hello

    I Chris (a.k.a. turbokeu. I am new to this forum but I really like your 4" blue clock. I am in the USA. Have you got a helper here for your clock using the WWVB time code? I would liek to voluntaire :)
    I have the schematic you posted, do you sell the Micro pre-programmed? I would gladly buy it from you.
    I tried sending you an email but it got returned.
    I wish I came across this forum sooner.
    I am building a clock using ~4320 14V led's in a 7-seg pattern. Money is tight so I dont have the pcb yet. Working on it.
    Well nice to met you and glad to be part of this forum.
    IS this thread still going?
    -tom
     
  5. Turbokeu

    Turbokeu Minimodder

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    Hi Tom, and welcome to the forums!
    I'm still alive but daily workload uses most of my (free) time...

    My provider's pop3 mailserver was down a few times yesterday but everything is working again now.

    In the meanwhile I sold two more LED clocks (one clock main board without display board for a 4.0" red LED clock, one complete 2.3" blue LED clock), and finished some more nixie clocks.

    I contacted a few PCB shops but the 4.0" display PCB board is really expensive to manufacture because of its size (68x14cm - 26.8x5.5") and not all manufacturers were able to handle the 68cm width.
    I received price offers between about 140 and 30 Euro/board, depending on the quantity (1-20).
    If I etch the board myself the costs are about 40 Euro just for materials (PCB and tinning solution), and I have to make it in two parts of 34x14cm.

    At the time being the clock code still only supports DCF77 decoding.
    I think therefore that a programmed PIC would not be of great use to you.
    I have some Maxim I²C DS1307 RTC chips and DS32KHZ temperature controlled precision Xtal oscillators laying around that I liked to use with the LED clock.

    Also thinking about using a cheap GPS module and decode the NMEA code for time keeping (that way the clock code would be usable over the whole world).
    I found a complete documentation about the WWVB signal coding but I'm afraid I can't invest the time to write a WWVB decoding routine at the moment (although this would be a new challenge to me)...

    Since about a week I finally managed to continue the development/testing of the code for my 9-digit IW-18 VFD clock after several months of inactivity. It now works great with Proteus VSM simulator, I just have to optimize the display routines and then test the HW/SW on a bread board.
    Also testing some SMPS circuits to generate the needed +50VDC anode/grid voltage and the 5VAC filament voltage for the IW-18 tube.

    I have started to work on the code for the 19-digit red 5x7 dotmatrix messaging display that I got for free.
    Parts of this code will then be used in my 10-digit 2.1" blue 5x7 dotmatrix LED clock.

    CD :)
     
  6. SteveyG

    SteveyG Electromodder

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    Hi Tom,

    I don't sell the displays, no - it was just a project :) If you have any questions though, I'll be more than happy to help out. Post questions in this thread if they are vaguely relevant and then maybe everyone can learn.

    The thread is still going, but for me - I only really get time at weekends now because work is eating up all my time, so personal projects are put on the back burner a little. I also need some inspiration for something a little different...

    edit:

    Sounds like you've been busy Chris! I was thinking about trying a GPS module for timekeeping, but have yet to see one at a reasonable cost. Might have a look for that DS32KHZ temperature controlled crystal you mention though, sounds good (and expensive).
     
  7. Turbokeu

    Turbokeu Minimodder

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    Hi Stevey,

    Like you work is eating all my time (even sometimes weekends!).

    I remember a GPS module for under 45 Euro (+/- 30GBP), the guy had about 20 of them. Will look if I can find back his coordinates.

    The DS32kHZ is accurate to +/- 1 minute/year, which is far better than the accuracy of a DS1307 or PCF8583.
    It is used as external precision oscillator for the Maxim DSxxxx RTC chips.
    I sampled them directly from Maxim (through my company).

    CD :)
     
  8. SteveyG

    SteveyG Electromodder

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    Yeah I found them on the Maxim site. They're cheaper than I was expecting since I was thinking of the crystals contained within a 40 degree chamber rather than this type which just uses compensating electronics. 1 second a year isn't bad though - I might go ahead and order some of these and connect them to the Timer 1 oscillator pin for timekeeping.
     
  9. tomjediknightt

    tomjediknightt What's a Dremel?

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    thanks, nice to meet you

    Thanks. Would you allow a schematic? I did find in an older nuts and volts issuse a dotmatrix display but had to be connected to a pc. But for you guys it looks like it can be decoded to work with a pic (or micro of some kind).
    I dont know how to program micros yet, but just ordered my first beginners guide for Pic micros. I am looking forward to it.
    I hope I can make a project to publish sometime. I have some very kool ideas but i am afraid that no programing experiece is killing me. And everyone I asked for help wants a ton of money. Bummer. I asked you cause you did the dotmatrix thingy. I personally think it is very cool. I like it. I have something simular in mind but using a neat font. SO i guess it can be done with any font you like as long as you decode the font you want. Make sense?
    So yeah, I like to stay in touch, you and chris really know your stuff.
    There is a site (lnstechnolgies) http://www.techkits.com/ that sells a 2.3" clock. Using an atmel chip, at89c1051. But no GPS time keeping and no power fail mode. Oh well, I got one and its kool.
    thanks for responding.
    -tom
     
  10. tomjediknightt

    tomjediknightt What's a Dremel?

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    That would be kool

    Chris,
    Glad to hear from you. I have (sometimes unbearable) too much time on my hands. I jsut ordered my first book for Intro to pic programming. I am excited. I have some kool projects, just no way to program a chip to run them. Kinda like reverse engineering. I got the displays down on how I want the clock to look like, but no one to help code. Everyone wants a ton of money. I knwo it isnt an overnite thing, but darn. But i am goign to start learning.
    Also, about the pcb board thing. Here in the states is called Express PCB. check this out here: http://www.expresspcb.com/
    They have a size limit too, but I think your clock in 2 boards will still be ok. These people are top notch qualitly and are resonabley priced.
    www.techkits.com has a big 2.3" clock kit. It is kool. I changed it to green. I dont like red. Red is always the standard for a long time. Glad to see other colors becoming available.

    I liek your nixie clock idea. Cant wait to see it. Looks kool. I got some IN-12A and some IV-22's. but dont have the money to go further yet. (YET!) but soon. looking like spring b4 i can invest into some serious amount of parts.

    Express PCB can do you 4" clock baord in 2 boards. max is 14x12 i think. They offer free software too to desing your boards. The you submit your order via thier server and in a few short days you have yr board. They say they ship world wide. SO check it out and let me know.

    I am looking into the green 4" from lc-led. and goign to subit a quote from kwality for thier 12". I might just make my own 12". Actually i got a pcb layout for a 6x9 display. using ~368 per 7-seg. 14v LED so i can run them on a 12v power supply. Easier I think. The LED has it's own resister built in so it was a saver on the pcb layout. I'll try to post a picture soon. if you get the express pcb program, let me know I can send you a layout and tell me what you think. if ok with you?
    well take it easy, and glad to meet you. You truely know your electronic stuff.
    -tom
     
  11. Turbokeu

    Turbokeu Minimodder

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    If I may advise you: start learning PIC assembler (there are a few good tutorials on the net), and carefully read the datasheet of the 16F628 microcontroller (the datasheet is your bible when you write code for your PIC).
    The 16F628(A) is the best PIC to start with (and cheap).
    Also download the free development environment (MPLAB) from Microchip.
    There are cheap DIY PIC-programmer schematics available.

    Assembler programming is more complicated in the beginning but once you are used to it you can control every bit/byte of your PIC.
    Afterwards you can still use a higher level Basic or C compiler but at least you will know every low level possibility of your PIC.

    There are lots of projects/code snippets/routines with/for PIC's available on the internet.
    Start with simple projects from others and try to understand the code, and adapt the code and hardware to your needs.
    That's how I started with PICs.

    There are some pictures of some of my nixie clocks in this same thread here and here.
    Thanks, I will have a look at their manufacturing capabilities and pricing.

    I already had a look at Kwality Photonics for their 12" display segments.
    If you ask them for a quote please let me know their conditions and pricing, I'm quite interested too.

    Yes please, post a picture.
    I just downloaded ExpressPCB, I will install and try it out at home tonight, so you can send me your layout.

    Chris :)
     
  12. SteveyG

    SteveyG Electromodder

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    Good advice. The way I started was just turning on an LED, then an LED controlled by a switch, then flashing the LED, then flashing lots of LEDs, software PWM on lots of LEDs, then playing with all of the peripherals which do some of the tasks I'd previously done in software...

    Assembly language requires a very different mind set to start off with compared to any high level languages, but now I find myself fustrated if I have to use high level languages that I can't do some of the stuff you can with assembler. :rolleyes:

    I didn't actually draw a proper schematic for my display - I just drew sections of it in a log book. THIS guy has used a similar fundamental architecture to my own, and that schematic should give you a good start to creating your own matrix display.
     
  13. eutronix

    eutronix What's a Dremel?

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    Hi Chris,

    I'm still around too. About ready to send the files off for the clock to the board house now. We too plan to play with the Maxim +/- 1 min/ year RTCs, but we will be using the SPI version (DS3234) instead. GPS is nice, but more limited than LF radio because you must have a window or something similar for the signal to pass. We are also considering having some custom LED clock displays made up with various colors available. I will try to post as we progress.

    Stu
     
  14. tomjediknightt

    tomjediknightt What's a Dremel?

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    Thanks. I will look omto it. Not sure yet which chip the book recomends. But looking forward to it. I really like to learn how to control LED's. SO i have your's and chris's advice handy. I downloaded the pdf datasheet for the 16F628A micro. Looks complacated but will work at it. If i can learn the 8085 from assembly, then I think I can learn the pic's.
    Jameco electronics has alot of pic's to choose from. And books and programmers. I was looking at the pickit2. We'll see.
    i'll let you guys know when I get the book. Thanks again.
    -tom
     
  15. tomjediknightt

    tomjediknightt What's a Dremel?

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    Since we are talking about clocks. I have brought several over the years so I thought I would share the info.
    WWW.Qkits.com has a neat clock using a pic micro. Called "the multifunction clock" it is cool and has many extra cool stuff.
    I also go tthe PIC micro clock which jas the hours and minutes 2.3" and smaller displays for the seconds. Cool but simple.
    THEN, I got the jumbo clock and binary clock from LNS technologies (www.techkits.com). Nice and simple, no date function but it is kinda neat. I changed my displays to green.
    My personal favorite of all has to be the "Clock Watchers" or it is really called "The Messmeriser clock" from www.jaycar.com This is a very cool effect. The seconds go around the circle of the clock backwards.
    Anyways these are some cool clocks that you should check out just for fun. Who know what might come next.....
     
  16. Turbokeu

    Turbokeu Minimodder

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    @tomjediknightt:

    A great (but expensive!) simulation software is Proteus VSM from Labcenter Electronics.
    I use it since about 5-6 years (I started with version 4.5) and couldn't do anymore without it.

    It does not only simulate your complete analog or digital hardware schematic but also executes your PIC code, all in real time, and with lots of realtime debugging tools (break points, step by step execution, logic analyzer, oscilloscope, voltmeter, amperemeter, counters, signal generator, pattern generator, traces, graphs,...).

    My projects are 99% working in Proteus before I even start to build the circuit on bread board.

    CD :)
     
  17. Turbokeu

    Turbokeu Minimodder

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    Hi Stu!
    Glad to hear from you again.

    Didn't know about the reception issues with GPS (the only GPS that I own is builtin in my car).
    That only leaves me RTC or DS32kHz + RTC as time sync in my clocks for people living outside of Europe.

    And yes, do post your progressions.

    Chris :)
     
  18. tomjediknightt

    tomjediknightt What's a Dremel?

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    I already had a look at Kwality Photonics for their 12" display segments.
    If you ask them for a quote please let me know their conditions and pricing, I'm quite interested too.

    hey Chris,
    I got a reply frpm kwality Photonics about there jumbo displays. Turns out that they are the indivual segments then you have to put them together. Shipping was kinda high for domestic but they will give me a quote on mon.
    will let u know then
    -tom
     
  19. tomjediknightt

    tomjediknightt What's a Dremel?

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    Hey Chris,
    I checked out the pricing for the software you told me about. the pic 16 starter kit is only 150. Not that bad. We'll see. Looking into different boards stuff right now. But thanks, I will defentily keep it in mind.
     
  20. tomjediknightt

    tomjediknightt What's a Dremel?

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    Hi Chris,
    Your email isn't working. Again i get mail returned to me.
    I got a reply from Kwality the pricing isnt too bad but we'll see.
    -tom
     

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