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From: D Yuniskis on 21 Jan 2010 11:47 Hi Uwe, Uwe Hercksen wrote: > > D Yuniskis schrieb: > >> [I vacillate between preferring B or C size drawings. C is nice >> in that it reduces to A nicely (i.e., with the same aspect ratio) >> OTOH, B is nice because reducing to A leaves room along the >> binding edge -- which must be located "above" the drawing! -- for >> three hole punch *or* more professional binding. And, B size >> can always be reproduced full size with "fold outs". (frown) B >> size (reduced or otherwise) is currently en vogue -- perhaps a >> consequence of my aging eyes? :> ] > > in Germany we have well defined paper formats, all these have the same > aspect ratio and the next larger format has exactly the double area of > the smaller one. Perfect for reduction and magnification. <grin> Unfortunately, not that simple on this side of the pond. The aspect ratio alternates with each successive paper size. E.g., 8.5x11 -> 11x17 -> 17x22 (same aspect as 8.5x11) -> 22x34 (same aspect as 11x17). Sometimes, it can be a win as you can deliberately chose a size and orientation that will scale to fit something nicely (e.g., B scaled to fit on an A gives you a nice margin). But, it is something that every designer stumbles over sooner or later when they get tired of large paper formats.
From: Joel Koltner on 21 Jan 2010 12:06 "krw" <krw(a)att.bizzzzzzzzzzz> wrote in message news:1flfl5l4m1qui1mv431amlbr9cvvl3lkr7(a)4ax.com... > I wouldn't even go there. Too many ways for things to go wrong. Think of it as just like a hierachical block ("all your bypass caps are belong to us") -- you just can't "push" into it explicitly. :-)
From: John Fields on 21 Jan 2010 12:59 On Wed, 20 Jan 2010 17:33:28 -0700, D Yuniskis <not.going.to.be(a)seen.com> wrote: >Exactly! Read my original comment: > >"E.g., RUN and STOP instead of RUN and RUNN (or NRUN)." > >Obviously, this refers to *two* signals. One of those is the >complement of the other (RUN -> RUNn, RUN -> STOP). The point I >was making is that I will *avoid* the "_n" in favor of choosing a >signal name that inherently implies the negation of its counterpart. >YES -> NO. RUN -> STOP. LEFT -> RIGHT. > >This avoids the "negation" issue for the most part (i.e., always >name "negative" signals with their antonyms) --- I don't understand what you're saying, but what works for me is to name the signal appropriately and then to assign it the polarity which results in the desired action being asserted. For example: (View in Courier) If have a signal which goes high and I want to use that signal to trigger an RS latch which will, say, start a motor, then I'll call the signal START and I'll wire it into a pair of positive true NORs like this: START>----A _ NOR Y--+ +--B | | | | _ A +-----Y NOR B Let's also say that the signal required by the controller, which will turn the motor on, is a momentary low-going signal. Then the signal chain would look like this: CONTROLLER +--------------+ START>----A _ _____ |_____ ___| NOR Y--+-->START>---O|START ON/OFF|--[MOTOR] +--B | | | | | | | | _ A +-----Y NOR B To finish it up, let's say the either the controller or the user can turn the motor off, and that either must generate a momentary low to do that, with both signals staying high the rest of the time. Then we have: CONTROLLER +--------------+ START>----A _ _____ |__ ___| OR Y-----+-->START>---O|ST ON/OFF|--[MOTOR] +--B U1 | | | | | ____ |__ ____| +-----------|-->STOP-----O|SP STOP|O--+ | | | | | | _ A--+ _ +--------------+ | +-----Y OR A----------------------------+ U2 B---Y _ OR U3 B--+ ____ | STOP>---------------------+ Notice that all of the gates are functionally ORs but, because of the annotation being applied to indicate function, in the real world U1 and U2 would be something like HC02 NORs, and U3 (being its De Morgan equivalent)something like an HC00 NAND. JF
From: krw on 21 Jan 2010 19:46 On Thu, 21 Jan 2010 11:59:21 -0600, John Fields <jfields(a)austininstruments.com> wrote: >On Wed, 20 Jan 2010 17:33:28 -0700, D Yuniskis ><not.going.to.be(a)seen.com> wrote: > > > >>Exactly! Read my original comment: >> >>"E.g., RUN and STOP instead of RUN and RUNN (or NRUN)." >> >>Obviously, this refers to *two* signals. One of those is the >>complement of the other (RUN -> RUNn, RUN -> STOP). The point I >>was making is that I will *avoid* the "_n" in favor of choosing a >>signal name that inherently implies the negation of its counterpart. >>YES -> NO. RUN -> STOP. LEFT -> RIGHT. >> >>This avoids the "negation" issue for the most part (i.e., always >>name "negative" signals with their antonyms) > >--- >I don't understand what you're saying, but what works for me is to name >the signal appropriately and then to assign it the polarity which >results in the desired action being asserted. > >For example: (View in Courier) > >If have a signal which goes high and I want to use that signal to >trigger an RS latch which will, say, start a motor, then I'll call the >signal START and I'll wire it into a pair of positive true NORs like >this: > > >START>----A _ > NOR Y--+ > +--B | > | | > | _ A > +-----Y NOR > B > >Let's also say that the signal required by the controller, which will >turn the motor on, is a momentary low-going signal. Then the signal >chain would look like this: > > CONTROLLER > +--------------+ >START>----A _ _____ |_____ ___| > NOR Y--+-->START>---O|START ON/OFF|--[MOTOR] > +--B | | | > | | | | > | _ A > +-----Y NOR > B _____ Except that START and START are not complementary. In this case _____ _______ _____________ START should be something like RUNNING or START_LATCHED or some such. > >To finish it up, let's say the either the controller or the user can >turn the motor off, and that either must generate a momentary low to do >that, with both signals staying high the rest of the time. > >Then we have: > > CONTROLLER > +--------------+ >START>----A _ _____ |__ ___| > OR Y-----+-->START>---O|ST ON/OFF|--[MOTOR] > +--B U1 | | | > | | ____ |__ ____| > +-----------|-->STOP-----O|SP STOP|O--+ > | | | | | > | _ A--+ _ +--------------+ | > +-----Y OR A----------------------------+ > U2 B---Y _ OR > U3 B--+ >____ | >STOP>---------------------+ > >Notice that all of the gates are functionally ORs but, because of the >annotation being applied to indicate function, in the real world U1 and >U2 would be something like HC02 NORs, and U3 (being its De Morgan >equivalent)something like an HC00 NAND. YES! Thank you!
From: krw on 21 Jan 2010 19:47
On Thu, 21 Jan 2010 09:06:12 -0800, "Joel Koltner" <zapwireDASHgroups(a)yahoo.com> wrote: >"krw" <krw(a)att.bizzzzzzzzzzz> wrote in message >news:1flfl5l4m1qui1mv431amlbr9cvvl3lkr7(a)4ax.com... >> I wouldn't even go there. Too many ways for things to go wrong. > >Think of it as just like a hierachical block ("all your bypass caps are belong >to us") -- you just can't "push" into it explicitly. :-) It's a special case, one that likely wouldn't be used enough for it to be obvious. No thanks. |