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Re: [cosmacelf] Re: OT: Starwars Day Contest

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  • Lee Hart
    ... It does sound entertaining. Part of the fun is that they excluded the automatic knee-jerk first choice of every young engineer by excluding microcomputers.
    Message 1 of 29 , Apr 27, 2013
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      "joshbensadon" wrote:
      >> A local electronics surplus store is having a contest to build a
      >> switch that turns on with a single click and off with a double
      >> click. No programmable devices allowed, must all be done through
      >> regular logic.

      jdrose_8_bit wrote:
      > That seems like a lot of fun. Seems fairly simple too. Mr. Hart could
      > design the winning circuit in his sleep.

      It does sound entertaining. Part of the fun is that they excluded the
      automatic knee-jerk first choice of every young engineer by excluding
      microcomputers. It's a classic think-outside-the-box problem! :-)

      However, that still leaves you with dozens of ways to do it. I'll bet
      you could pick every possible technology (mechanical, pneumatic,
      hydraulic, electrical switch, relays, vacuum tubes, neon lamps,
      transistors, ICs, even microcomputers *without* a program) and solve the
      problem with every single one of them. Even a mad Rube Goldberg / Heath
      Robinson solution could do it.

      --
      Failure is only the opportunity to begin again more intelligently.
      -- Henry Ford
      --
      Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
    • Charles Richmond
      If the double-click is like the double-click of a mouse, then the clicks have to occur within a certain time of each other to count. Otherwise it s just two
      Message 2 of 29 , Apr 27, 2013
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        If the "double-click" is like the double-click of a mouse, then the
        clicks have to occur within a certain time of each other to count.
        Otherwise it's just two single clicks.

        In most GUI systems (Windows, Mac OS, etc.) there is a place to set
        the double-click time limit. Now, for this special-purpose digital
        circuitry, I'd think that such an adjustment would *not* be
        necessary... but I think you still should set a time limit between
        clicks for the clicks to count as a double-click.


        On Apr 27, 2013, at 3:43 PM, jdrose_8_bit wrote:

        > That seems like a lot of fun.
        >
        > Seems fairly simple too. Mr. Hart could design the winning circuit
        > in his sleep.
        >
        > What is the first thing to do. Make the logic truth table?
        >
        > Operation:
        >
        > Button Push. LED on.
        > Button Push. No change.
        > Button Push. LED off.
        >
        > Is there something like a 3 position 4017 counter?
        >
        > 1, 2 pins connected to LED and the number 3 pin not.
        >
        > Each push button would cycle 1 step through the counter.
        > 1 LED, IC, pushbutton and dropping resistor.
        >
        > --- In cosmacelf@yahoogroups.com, "joshbensadon" <joshbensadon@...>
        > wrote:
        > >
        > > Hi,
        > >
        > > A local electronics surplus store is having a contest to build a
        > switch that turns on with a single click and off with a double
        > click. No programmable devices allowed, must all be done through
        > regular logic.
        > >
        > > It's open to the public. It sounds like a fun challenge, nothing
        > big.
        > >
        > > I plan to enter, although I don't enter to win, but for the fun.
        > >
        > > Please see "Starwars Contest.pdf" in the files section.
        > >
        > > Cheers,
        > > Josh
        > >
        >
        >
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        --
        +----------------------------------------+
        |.....Charles and Francis Richmond.......|
        |........................................|
        |..plano dot net at aquaporin4 dot com...|
        +----------------------------------------+
      • William Donnelly
        Yes. Otherwise the simplest solution is a 3-throw 3-pole pushbutton switch. That would actually pass their rules (I think), but isn t an ideal solution, and
        Message 3 of 29 , Apr 27, 2013
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          Yes.

          Otherwise the simplest solution is a 3-throw 3-pole pushbutton switch.

          That would actually pass their rules (I think), but isn't an ideal solution, and
          kind of goes against the intrinsic nature of the contest and its ultimate goal. (?)

          You could have a tiny rheostat that can be accessed with a tiny flat-blade screwdriver
          to set the double-click timeout.

          – Bill
           
          On 4/27/2013 10:48 PM, Charles Richmond wrote:
          If the "double-click" is like the double-click of a mouse, then the  
          clicks have to occur within a certain time of each other to count.   
          Otherwise it's just two single clicks.
          
          In most GUI systems (Windows, Mac OS, etc.) there is a place to set  
          the double-click time limit.  Now, for this special-purpose digital  
          circuitry, I'd think that such an adjustment would *not* be  
          necessary... but I think you still should set a time limit between  
          clicks for the clicks to count as a double-click.
          
          

        • Andrew Wasson
          Yes, I was thinking that as well because if our young Jedi can bump the switch once in combat, he could most certainly bump it twice. I thought that rather
          Message 4 of 29 , Apr 27, 2013
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            Yes, I was thinking that as well because if our young Jedi can bump the switch once in combat, he could most certainly bump it twice. I thought that rather than specifically time the double click, I would discard the first off click if the second click didn't occur after a reasonable amount of time. Same sort of idea.

            Andrew

            On 2013-04-27, at 10:48 PM, Charles Richmond <old_computers@...> wrote:

            > If the "double-click" is like the double-click of a mouse, then the
            > clicks have to occur within a certain time of each other to count.
            > Otherwise it's just two single clicks.
            >
            > In most GUI systems (Windows, Mac OS, etc.) there is a place to set
            > the double-click time limit. Now, for this special-purpose digital
            > circuitry, I'd think that such an adjustment would *not* be
            > necessary... but I think you still should set a time limit between
            > clicks for the clicks to count as a double-click.
            >
            >
            > On Apr 27, 2013, at 3:43 PM, jdrose_8_bit wrote:
            >
            >> That seems like a lot of fun.
            >>
            >> Seems fairly simple too. Mr. Hart could design the winning circuit
            >> in his sleep.
            >>
            >> What is the first thing to do. Make the logic truth table?
            >>
            >> Operation:
            >>
            >> Button Push. LED on.
            >> Button Push. No change.
            >> Button Push. LED off.
            >>
            >> Is there something like a 3 position 4017 counter?
            >>
            >> 1, 2 pins connected to LED and the number 3 pin not.
            >>
            >> Each push button would cycle 1 step through the counter.
            >> 1 LED, IC, pushbutton and dropping resistor.
            >>
            >> --- In cosmacelf@yahoogroups.com, "joshbensadon" <joshbensadon@...>
            >> wrote:
            >>>
            >>> Hi,
            >>>
            >>> A local electronics surplus store is having a contest to build a
            >> switch that turns on with a single click and off with a double
            >> click. No programmable devices allowed, must all be done through
            >> regular logic.
            >>>
            >>> It's open to the public. It sounds like a fun challenge, nothing
            >> big.
            >>>
            >>> I plan to enter, although I don't enter to win, but for the fun.
            >>>
            >>> Please see "Starwars Contest.pdf" in the files section.
            >>>
            >>> Cheers,
            >>> Josh
            >>>
            >>
            >>
            >> <!-- #ygrp-mkp { border: 1px solid #d8d8d8; font-family: Arial;
            >> margin: 10px 0; padding: 0 10px; } #ygrp-mkp hr { border: 1px solid
            >> #d8d8d8; } #ygrp-mkp #hd { color: #628c2a; font-size: 85%; font-
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            >> color: #e0ecee; float: left; font-family: Verdana; font-size: 10px;
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            >> span:first-child { text-transform: uppercase; } #activity span a
            >> { color: #5085b6; text-decoration: none; } #activity span span
            >> { color: #ff7900; } #activity span .underline { text-decoration:
            >> underline; } .attach { clear: both; display: table; font-family:
            >> Arial; font-size: 12px; padding: 10px 0; width: 400px; } .attach
            >> div a { text-decoration: none; } .attach img { border: none;
            >> padding-right: 5px; } .attach label { display: block; margin-
            >> bottom: 5px; } .attach label a { text-decoration: none; }
            >> blockquote { margin: 0 0 0 4px; } .bold { font-family: Arial; font-
            >> size: 13px; font-weight: 700; } .bold a { text-decoration: none; }
            >> dd.last p a { font-family: Verdana; font-weight: 700; } dd.last p
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            >> table div div a { text-decoration: none; } div.attach-table
            >> { width: 400px; } div.file-title a, div.file-title a:active,
            >> div.file-title a:hover, div.file-title a:visited { text-decoration:
            >> none; } div.photo-title a, div.photo-title a:active, div.photo-
            >> title a:hover, div.photo-title a:visited { text-decoration: none; }
            >> div#ygrp-mlmsg #ygrp-msg p a span.yshortcuts { font-family:
            >> Verdana; font-size: 10px; font-weight: normal; } .green { color:
            >> #628c2a; } .MsoNormal { margin: 0 0 0 0; } o { font-size: 0; }
            >> #photos div { float: left; width: 72px; } #photos div div { border:
            >> 1px solid #666666; height: 62px; overflow: hidden; width: 62px; }
            >> #photos div label { color: #666666; font-size: 10px; overflow:
            >> hidden; text-align: center; white-space: nowrap; width: 64px; }
            >> #reco-category { font-size: 77%; } #reco-desc { font-size:
            >> 77%; } .replbq { margin: 4px; } #ygrp-actbar div a:first-child { /*
            >> border-right: 0px solid #000;*/ margin-right: 2px; padding-right:
            >> 5px; } #ygrp-mlmsg { font-size: 13px; font-family: Arial,
            >> helvetica,clean, sans-serif; *font-size: small; *font: x-small; }
            >> #ygrp-mlmsg table { font-size: inherit; font: 100%; } #ygrp-mlmsg
            >> select, input, textarea { font: 99% Arial, Helvetica, clean, sans-
            >> serif; } #ygrp-mlmsg pre, code { font:115% monospace; *font-size:
            >> 100%; } #ygrp-mlmsg * { line-height: 1.22em; } #ygrp-mlmsg #logo
            >> { padding-bottom: 10px; } #ygrp-msg p a { font-family: Verdana; }
            >> #ygrp-msg p#attach-count span { color: #1E66AE; font-weight: 700; }
            >> #ygrp-reco #reco-head { color: #ff7900; font-weight: 700; } #ygrp-
            >> reco { margin-bottom: 20px; padding: 0px; } #ygrp-sponsor #ov li a
            >> { font-size: 130%; text-decoration: none; } #ygrp-sponsor #ov li
            >> { font-size: 77%; list-style-type: square; padding: 6px 0; } #ygrp-
            >> sponsor #ov ul { margin: 0; padding: 0 0 0 8px; } #ygrp-text { font-
            >> family: Georgia; } #ygrp-text p { margin: 0 0 1em 0; } #ygrp-text
            >> tt { font-size: 120%; } #ygrp-vital ul li:last-child { border-
            >> right: none !important; } -->
            >
            > --
            > +----------------------------------------+
            > |.....Charles and Francis Richmond.......|
            > |........................................|
            > |..plano dot net at aquaporin4 dot com...|
            > +----------------------------------------+
            >
            >
            >
            >
            >
            >
            > ------------------------------------
            >
            > ========================================================
            > Visit the COSMAC ELF website at http://www.cosmacelf.comYahoo! Groups Links
            >
            >
            >
          • Kevin
            Honestly, this sounds like a job for an analog design.
            Message 5 of 29 , Apr 28, 2013
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              Honestly, this sounds like a job for an analog design.


              --- In cosmacelf@yahoogroups.com, "joshbensadon" <joshbensadon@...> wrote:
              >
              > Hi,
              >
              > A local electronics surplus store is having a contest to build a switch that turns on with a single click and off with a double click. No programmable devices allowed, must all be done through regular logic.
              >
              > It's open to the public. It sounds like a fun challenge, nothing big.
              >
              > I plan to enter, although I don't enter to win, but for the fun.
              >
              > Please see "Starwars Contest.pdf" in the files section.
              >
              > Cheers,
              > Josh
              >
            • Lee Hart
              ... Let s see... *simplest* solution... Obviously, you can build an alternate-action pushbutton. Push once, it s on. Push again, it s off. Use a mechanism like
              Message 6 of 29 , Apr 28, 2013
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                William Donnelly wrote:
                > the simplest solution is a 3-throw 3-pole pushbutton switch.

                Let's see... *simplest* solution...

                Obviously, you can build an alternate-action pushbutton. Push once, it's
                on. Push again, it's off. Use a mechanism like the clicker in a
                ballpoint pen, but modify it so it takes 3 clicks to make a cycle. The
                cycles would be off-on-on, so it only takes 1 click to turn it on, but 2
                clicks to turn off.

                If you want a simple electrical solution, build a voltage doubler with
                two diodes and two capacitors. The pushbutton connects either 0v or 5v
                to the input. Have some sensing circuit that needs more than 5v to turn
                on. Pick a load resistor to set the RC time constant for how closely
                together the two button pushes have to be.

                The sensing circuit can be almost anything; latching relay coil, vacuum
                tube, transistor, IC, etc.
                --
                The principal defect in a storage battery is its modesty. It does not
                spark, creak, groan, nor slow down under overload. It does not rotate.
                It works where it is, and will silently work up to the point of
                destruction without making any audible or visible signs of distress.
                -- Electrical Review, 1902
                --
                Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
              • jdrose_8_bit
                ... That is an interesting idea. It violates the letter of the contest but not the spirit of the contest. Seems like the 1802 would be ideally suited for the
                Message 7 of 29 , Apr 28, 2013
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                  --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@...> wrote:

                  >
                  > Part of the fun is that they excluded the
                  > automatic knee-jerk first choice of every young engineer by excluding
                  > microcomputers. It's a classic think-outside-the-box problem! :-)
                  >
                  > However, that still leaves you with dozens of ways to do it... even microcomputers *without* a program)...
                  >

                  That is an interesting idea. It violates the letter of the contest but not the spirit of the contest.

                  Seems like the 1802 would be ideally suited for the exercise. No program, no RAM, only the 1802 and external components.


                  --- In cosmacelf@yahoogroups.com, William Donnelly <william@...> wrote:
                  >
                  > Yes.
                  >
                  > Otherwise the simplest solution is a 3-throw 3-pole pushbutton switch.
                  >
                  > That would actually pass their rules (I think)
                  >

                  I think so.


                  --- In cosmacelf@yahoogroups.com, Andrew Wasson <awasson@...> wrote:
                  >
                  > Yes, I was thinking that as well because if our young Jedi can bump the switch once in combat, he could most certainly bump it twice. I thought that rather than specifically time the double click, I would discard the first off click if the second click didn't occur after a reasonable amount of time. Same sort of idea.
                  >


                  Indeed.

                  After a relatively small lapse of time, the second setting essentially becomes the defacto ON setting from the perspective of the fencer.

                  I think it is a very serious oversight by the contest designers to not include that function in the circuit.
                • jdrose_8_bit
                  ... OK. The author of the contest does write but to turn it off, you have to push the button twice in succession. They do not define time limits of
                  Message 8 of 29 , Apr 28, 2013
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                    --- In cosmacelf@yahoogroups.com, "jdrose_8_bit" <rarecoinbuyer@...> wrote:

                    > --- In cosmacelf@yahoogroups.com, Andrew Wasson <awasson@> wrote:
                    > >
                    > > Yes, I was thinking that as well because if our young Jedi can bump the switch once in combat, he could most certainly bump it twice.
                    >> I thought that rather than specifically time the double click, I would discard the first off click if the second click didn't occur after a reasonable amount of time.
                    >>Same sort of idea.
                    >
                    >
                    > I think it is a very serious oversight by the contest designers to not include that function in the circuit.
                    >

                    OK. The author of the contest does write "but to turn it off, you have to push the button twice in succession."

                    They do not define time limits of "succession" but I guess it is implied that the second push must happen in a very short time.
                  • Lee Hart
                    ... For example, hard-wire the data bus for a Long Branch instruction. The pushbutton single-steps the 1802. The 1802 will do a Fetch, Execute, Execute, Fetch,
                    Message 9 of 29 , Apr 28, 2013
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                      >> However, that still leaves you with dozens of ways to do it... even
                      >> microcomputers *without* a program)...

                      jdrose_8_bit wrote:
                      > That is an interesting idea. It violates the letter of the contest
                      > but not the spirit of the contest.
                      >
                      > Seems like the 1802 would be ideally suited for the exercise. No
                      > program, no RAM, only the 1802 and external components.

                      For example, hard-wire the data bus for a Long Branch instruction. The
                      pushbutton single-steps the 1802. The 1802 will do a Fetch, Execute,
                      Execute, Fetch, Execute, Execute... machine cycle sequence. So State
                      Code output SC0 will be low, high, high, low, high high... Define
                      low=off, and high=on and you have a solution. :-)

                      --
                      The most dangerous enemy of a better solution is an existing one that
                      is just good enough. -- Eric S. Raymond
                      --
                      Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
                    • Kevin
                      But then you would have a program.
                      Message 10 of 29 , Apr 28, 2013
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                        But then you would have a program.

                        --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@...> wrote:
                        >
                        > For example, hard-wire the data bus for a Long Branch instruction.
                      • jdrose_8_bit
                        That is an interesting observation. Is the hard wiring basically a ROM program made of discrete components? Or is it a hardware extension of the logic gates
                        Message 11 of 29 , Apr 28, 2013
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                          That is an interesting observation.

                          Is the hard wiring basically a ROM program made of discrete components? Or is it a hardware extension of the logic gates built into the microprocessor?


                          --- In cosmacelf@yahoogroups.com, "Kevin" <kriceslo@...> wrote:
                          >
                          > But then you would have a program.
                          >
                          > --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@> wrote:
                          > >
                          > > For example, hard-wire the data bus for a Long Branch instruction.
                          >
                        • Kevin
                          It s both.
                          Message 12 of 29 , Apr 28, 2013
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                            It's both.

                            --- In cosmacelf@yahoogroups.com, "jdrose_8_bit" <rarecoinbuyer@...> wrote:
                            >
                            > That is an interesting observation.
                            >
                            > Is the hard wiring basically a ROM program made of discrete components? Or is it a hardware extension of the logic gates built into the microprocessor?
                            >
                            >
                            > --- In cosmacelf@yahoogroups.com, "Kevin" <kriceslo@> wrote:
                            > >
                            > > But then you would have a program.
                            > >
                            > > --- In cosmacelf@yahoogroups.com, Lee Hart <leeahart@> wrote:
                            > > >
                            > > > For example, hard-wire the data bus for a Long Branch instruction.
                            > >
                            >
                          • Lee Hart
                            ... Yeah, it skirts the edge of the rules. I could see a judge deciding it either way. It s either a 1-instruction program , or just a way to connect logic
                            Message 13 of 29 , Apr 28, 2013
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                              Lee Hart wrote:
                              >>> For example, hard-wire the data bus for a Long Branch instruction.

                              "Kevin" wrote:
                              >> But then you would have a program.

                              jdrose_8_bit wrote:
                              > Is the hard wiring basically a ROM program made of discrete components? Or is it a hardware extension of the logic gates built into the microprocessor?

                              Yeah, it skirts the edge of the rules. I could see a judge deciding it
                              either way. It's either a 1-instruction "program", or just a way to
                              connect logic gates and flip-flops to achieve the desired result. :-)

                              --
                              The trouble ain't that there's too many fools, but that lightning ain't
                              distributed right. -- Mark Twain
                              --
                              Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
                            • Lee Hart
                              ... Actually, I think the way to go is to use the 1802 s DMA! -- You never change things by fighting the existing reality. To change something, build a new
                              Message 14 of 29 , Apr 28, 2013
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                                On 4/27/2013 11:21 AM, David W. Schultz wrote:
                                > Between rolling my own drive electronics and purchasing a Western
                                > Digital 2797 floppy disk controller I know which way I would go.
                                >
                                > For double density data the bit rate is 250Kb/sec so you have to handle
                                > a byte of data every 32 us. On an 1802 with a 2MHz clock that is once
                                > every four 2 cycle instructions.
                                >
                                > The fastest way to check for data in software is to connect the DRQ pin
                                > to an EF line and use a nice short one instruction loop to wait for it.

                                Actually, I think the way to go is to use the 1802's DMA!
                                --
                                You never change things by fighting the existing reality. To change
                                something, build a new model that makes the existing model obsolete. --
                                Buckminster Fuller
                                --
                                Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm
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