On 03/06/20 16:04, Bill Sloman wrote:> I used Orcad in 1991-93 in Cambridge for schematic capture and it wasn't too bad.I used Orcad around that tiemframe too, and was amazed at how fast decent schematics could be created and modified using a keyboard and without a mouse. Another engineer, quite reasonably, refused to believe it until I demonstrated it. I avoided the PCB layout, though. Moving on to a full Metal Graphics suite was painful. It made the easy things difficult. I need to learn KiCad now. Many accounts indicate that it is now usable, even good.
KiCad Spice, Anyone Tried It?
Started by ●June 2, 2020
Reply by ●June 3, 20202020-06-03
Reply by ●June 3, 20202020-06-03
On Wed, 3 Jun 2020 17:10:12 +0100, Tom Gardner <spamjunk@blueyonder.co.uk> wrote:>On 03/06/20 16:41, jlarkin@highlandsniptechnology.com wrote: >> On Wed, 3 Jun 2020 14:14:03 +0100, Tom Gardner >> <spamjunk@blueyonder.co.uk> wrote: >> >>> On 03/06/20 13:18, jlarkin@highlandsniptechnology.com wrote: >>>> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner >>>> <spamjunk@blueyonder.co.uk> wrote: >>>> >>>>> On 03/06/20 08:34, Ricketty C wrote: >>>>>> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >>>>>> about picking up really. It's about issues of multiple pages. They don't >>>>>> really support a flat, multi-page schematic. It must be hierarchical. So to >>>>>> have a two page schematic, you must have a top sheet and one or more lower >>>>>> sheets. >>>>> >>>>> As someone that hasn't used KiCad yet, but expects to soon, my >>>>> comment is "excellent" :) >>>>> >>>>> I have three peeves about many schematics that I see: >>>>> - principal signal flow in any random direction >>>>> - if a wire leaves one schematic, it isn't clear which >>>>> other schematic(s) is reappears on >>>>> - signal/bus wires that are named but not visually connected >>>>> >>>>> The latter really pisses me off, since on a PDF I have to >>>>> use ctrl-f to understand connectivity, and the schematic cannot >>>>> be usefully printed out. >>>>> >>>>> No, it isn't merely modern diagrams that do that, you also >>>>> find it in old Tek schematics. >>>>> >>>> >>>> I hate hierarchicals and busses and any abstraction that hides what's >>>> actually on the board. I do everything flat... currently a 31-page >>>> schematic with five basically identical output channels, each on its >>>> own sheet. I know exactly where R114 is. >>> >>> Yes, but what if you are presented with someone else's >>> schematic like that, and you need to find /all/ the >>> components connected to R114. >> >> I click a pin and the project explorer shows me the net name and all >> the connections. I click one of them and it jumps there. >> >> A heirarichal schematic is worse! > >Fine for the author. What about a customer (or other) that >doesn't have access to your schematic program?We rarely allow customers to see schematics. A trusted one, or one who pays, can have the PADS files and a PDF of the entire schematic. Many other pcb programs will open PADS files. The viewers are free from Mentor. It's essentially impossible for a customer to maintain our products; each needs a rack full of gear to test and cal. How does a heirarichal schematic make it easier to find connections on the schematic, or a physical part on a board?> > >>> Finding your way around your own schematics is comparatively >>> easy and reliable. >> >> I've drawn thousands of schematics. I can't remember them all. With >> decent discipline and good tools, I don't have to. >> >> I can open and work on a PADS schematic or PCB that we did 25 years >> ago. > >Fine, apart from the above caveat. >What about in another 25 years? > >I'll bet PDFs and dead trees will still be readable then. >We don't keep paper copies of schematics or layouts. I agree that PDFs, and the ability to read from USB hard drives, will be around for the life of the equipment. -- John Larkin Highland Technology, Inc Science teaches us to doubt. Claude Bernard
Reply by ●June 3, 20202020-06-03
On 03/06/20 16:51, jlarkin@highlandsniptechnology.com wrote:> On Wed, 3 Jun 2020 15:21:21 +0100, Tom Gardner > <spamjunk@blueyonder.co.uk> wrote: > >> On 03/06/20 08:34, Ricketty C wrote: >>> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >>> about picking up really. It's about issues of multiple pages. They don't >>> really support a flat, multi-page schematic. It must be hierarchical. So to >>> have a two page schematic, you must have a top sheet and one or more lower >>> sheets. >>> >>> The parts can have multiple units, but schematics can't have multiple pages. >>> That seems oddly inconsistent. >> >> Another viewpoint is to consider the analogous situation in >> large-scale software systems. >> >> For one person developing a small piece of code, nothing much >> is needed. >> >> But in a large system that requires modification over the years, >> it has been found necessary to develop techniques that have >> the same characteristics as hierarchical hardware schematics. >> >> Example 1: all the various UML structural component diagrams. >> >> Example 2: the currently fashionable "inversion of control" >> techniques. If you sit down and think about what they are >> attempting to rectify, and how they are doing it, then you >> see they are connecting stand-alone components and sub-components >> in a hierarchy.I don't think you are aware of what's in medium and large scale software.> A PCB is very different from code. Multiple copies have to be > assembled my manufacturing,The similarities outweigh the differences. Simple examples: operating systems, servers, server applications.> from purchased or fabricated parts.The similarities outweigh the differences. Simple examples: libraries, servers.> Each board needs to be inspected and tested.The similarities outweigh the differences. Simple examples: one application installed in different servers optionally in different companies.> If changes must be made, they > will be applied, per an ECO, to every board, by manufacturing.The similarities outweigh the differences. Simple examples: each application installed in each server.> Field changes are physical and expensive.The similarities outweigh the differences. Arguably it is more difficult to correctly change software.> A computer program doesn't need many identical copies of a subroutine. > A circuit board often does, but they usually wind up be not quite > exactly identical. They are certainly physically distinct, even if > they look alike on paper.The similarities outweigh the differences. Simple examples: objects, classes, and class hierarchies, definitions of things such as "a person" or "the time".> Computer programs don't need ground or power planes.Agreed, but so what!> They should have > test points and BIST, but they seldom do.No difference :(> Very different.Nope.
Reply by ●June 3, 20202020-06-03
On 03/06/20 17:33, jlarkin@highlandsniptechnology.com wrote:> On Wed, 3 Jun 2020 17:10:12 +0100, Tom Gardner > <spamjunk@blueyonder.co.uk> wrote: > >> On 03/06/20 16:41, jlarkin@highlandsniptechnology.com wrote: >>> On Wed, 3 Jun 2020 14:14:03 +0100, Tom Gardner >>> <spamjunk@blueyonder.co.uk> wrote: >>> >>>> On 03/06/20 13:18, jlarkin@highlandsniptechnology.com wrote: >>>>> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner >>>>> <spamjunk@blueyonder.co.uk> wrote: >>>>> >>>>>> On 03/06/20 08:34, Ricketty C wrote: >>>>>>> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >>>>>>> about picking up really. It's about issues of multiple pages. They don't >>>>>>> really support a flat, multi-page schematic. It must be hierarchical. So to >>>>>>> have a two page schematic, you must have a top sheet and one or more lower >>>>>>> sheets. >>>>>> >>>>>> As someone that hasn't used KiCad yet, but expects to soon, my >>>>>> comment is "excellent" :) >>>>>> >>>>>> I have three peeves about many schematics that I see: >>>>>> - principal signal flow in any random direction >>>>>> - if a wire leaves one schematic, it isn't clear which >>>>>> other schematic(s) is reappears on >>>>>> - signal/bus wires that are named but not visually connected >>>>>> >>>>>> The latter really pisses me off, since on a PDF I have to >>>>>> use ctrl-f to understand connectivity, and the schematic cannot >>>>>> be usefully printed out. >>>>>> >>>>>> No, it isn't merely modern diagrams that do that, you also >>>>>> find it in old Tek schematics. >>>>>> >>>>> >>>>> I hate hierarchicals and busses and any abstraction that hides what's >>>>> actually on the board. I do everything flat... currently a 31-page >>>>> schematic with five basically identical output channels, each on its >>>>> own sheet. I know exactly where R114 is. >>>> >>>> Yes, but what if you are presented with someone else's >>>> schematic like that, and you need to find /all/ the >>>> components connected to R114. >>> >>> I click a pin and the project explorer shows me the net name and all >>> the connections. I click one of them and it jumps there. >>> >>> A heirarichal schematic is worse! >> >> Fine for the author. What about a customer (or other) that >> doesn't have access to your schematic program? > > We rarely allow customers to see schematics. A trusted one, or one who > pays, can have the PADS files and a PDF of the entire schematic. Many > other pcb programs will open PADS files. The viewers are free from > Mentor.OK. That's one common case, but many situations aren't like that.> It's essentially impossible for a customer to maintain our products; > each needs a rack full of gear to test and cal.OK. That's one common case, but many situations aren't like that.> How does a heirarichal schematic make it easier to find connections on > the schematic, or a physical part on a board?You can trace connections with your eye (or finger!) on the schematic. It doesn't help finding a component on the PCB, but that information isn't in the schematic anyway.>>>> Finding your way around your own schematics is comparatively >>>> easy and reliable. >>> >>> I've drawn thousands of schematics. I can't remember them all. With >>> decent discipline and good tools, I don't have to. >>> >>> I can open and work on a PADS schematic or PCB that we did 25 years >>> ago. >> >> Fine, apart from the above caveat. >> What about in another 25 years? >> >> I'll bet PDFs and dead trees will still be readable then. >> > > We don't keep paper copies of schematics or layouts. I agree that > PDFs, and the ability to read from USB hard drives, will be around for > the life of the equipment.I /might/ keep paper copies, for legal reasons.
Reply by ●June 3, 20202020-06-03
onsdag den 3. juni 2020 kl. 14.18.53 UTC+2 skrev jla...@highlandsniptechnology.com:> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner > <spamjunk@blueyonder.co.uk> wrote: > > >On 03/06/20 08:34, Ricketty C wrote: > >> I guess I spoke too soon about KiCad being easy to pick up... well it isn't > >> about picking up really. It's about issues of multiple pages. They don't > >> really support a flat, multi-page schematic. It must be hierarchical. So to > >> have a two page schematic, you must have a top sheet and one or more lower > >> sheets. > > > >As someone that hasn't used KiCad yet, but expects to soon, my > >comment is "excellent" :) > > > >I have three peeves about many schematics that I see: > > - principal signal flow in any random direction > > - if a wire leaves one schematic, it isn't clear which > > other schematic(s) is reappears on > > - signal/bus wires that are named but not visually connected > > > >The latter really pisses me off, since on a PDF I have to > >use ctrl-f to understand connectivity, and the schematic cannot > >be usefully printed out. > > > >No, it isn't merely modern diagrams that do that, you also > >find it in old Tek schematics. > > > > I hate hierarchicals and busses and any abstraction that hides what's > actually on the board. I do everything flat... currently a 31-page > schematic with five basically identical output channels, each on its > own sheet. I know exactly where R114 is.since it is R1xx on page 1> > I do start a schematic with sheet 1 being the block diagram and sheet > list/table of contents. Sheets have both numbers and names in the PADS > pulldown menu.so whats the difference? I have a page 1 with a number of blocks and how they are connected each of those blocks is a schematic. It is possible to more than one block point to the same schematic but it doesn't have to, each can have its own so it just like your multipage schematic and if you print it you get all the pages even if some of them are the same except for designators
Reply by ●June 3, 20202020-06-03
On Wed, 3 Jun 2020 17:54:34 +0100, Tom Gardner <spamjunk@blueyonder.co.uk> wrote:>On 03/06/20 17:33, jlarkin@highlandsniptechnology.com wrote: >> On Wed, 3 Jun 2020 17:10:12 +0100, Tom Gardner >> <spamjunk@blueyonder.co.uk> wrote: >> >>> On 03/06/20 16:41, jlarkin@highlandsniptechnology.com wrote: >>>> On Wed, 3 Jun 2020 14:14:03 +0100, Tom Gardner >>>> <spamjunk@blueyonder.co.uk> wrote: >>>> >>>>> On 03/06/20 13:18, jlarkin@highlandsniptechnology.com wrote: >>>>>> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner >>>>>> <spamjunk@blueyonder.co.uk> wrote: >>>>>> >>>>>>> On 03/06/20 08:34, Ricketty C wrote: >>>>>>>> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >>>>>>>> about picking up really. It's about issues of multiple pages. They don't >>>>>>>> really support a flat, multi-page schematic. It must be hierarchical. So to >>>>>>>> have a two page schematic, you must have a top sheet and one or more lower >>>>>>>> sheets. >>>>>>> >>>>>>> As someone that hasn't used KiCad yet, but expects to soon, my >>>>>>> comment is "excellent" :) >>>>>>> >>>>>>> I have three peeves about many schematics that I see: >>>>>>> - principal signal flow in any random direction >>>>>>> - if a wire leaves one schematic, it isn't clear which >>>>>>> other schematic(s) is reappears on >>>>>>> - signal/bus wires that are named but not visually connected >>>>>>> >>>>>>> The latter really pisses me off, since on a PDF I have to >>>>>>> use ctrl-f to understand connectivity, and the schematic cannot >>>>>>> be usefully printed out. >>>>>>> >>>>>>> No, it isn't merely modern diagrams that do that, you also >>>>>>> find it in old Tek schematics. >>>>>>> >>>>>> >>>>>> I hate hierarchicals and busses and any abstraction that hides what's >>>>>> actually on the board. I do everything flat... currently a 31-page >>>>>> schematic with five basically identical output channels, each on its >>>>>> own sheet. I know exactly where R114 is. >>>>> >>>>> Yes, but what if you are presented with someone else's >>>>> schematic like that, and you need to find /all/ the >>>>> components connected to R114. >>>> >>>> I click a pin and the project explorer shows me the net name and all >>>> the connections. I click one of them and it jumps there. >>>> >>>> A heirarichal schematic is worse! >>> >>> Fine for the author. What about a customer (or other) that >>> doesn't have access to your schematic program? >> >> We rarely allow customers to see schematics. A trusted one, or one who >> pays, can have the PADS files and a PDF of the entire schematic. Many >> other pcb programs will open PADS files. The viewers are free from >> Mentor. > >OK. That's one common case, but many situations aren't like that. > > >> It's essentially impossible for a customer to maintain our products; >> each needs a rack full of gear to test and cal. > >OK. That's one common case, but many situations aren't like that. > > >> How does a heirarichal schematic make it easier to find connections on >> the schematic, or a physical part on a board? > >You can trace connections with your eye (or finger!) on the >schematic.The heirarichal schematics that I've seen, signals go into instances of boxes, and change net name inside each box. No thanks.> >It doesn't help finding a component on the PCB, but that >information isn't in the schematic anyway.R114 is on my schematic and on my PCB. The reference designator (50 mils high, 6 wide lines) fits next to the resistor on the top silk. What does a refdes look like on a heirarichal-schematic PCB? My channels are not always identical anyhow. I might decide to use three bypass caps over 5 channels. Or put the clock terminator in one. Or change a part value in one.> > >>>>> Finding your way around your own schematics is comparatively >>>>> easy and reliable. >>>> >>>> I've drawn thousands of schematics. I can't remember them all. With >>>> decent discipline and good tools, I don't have to. >>>> >>>> I can open and work on a PADS schematic or PCB that we did 25 years >>>> ago. >>> >>> Fine, apart from the above caveat. >>> What about in another 25 years? >>> >>> I'll bet PDFs and dead trees will still be readable then. >>> >> >> We don't keep paper copies of schematics or layouts. I agree that >> PDFs, and the ability to read from USB hard drives, will be around for >> the life of the equipment. > >I /might/ keep paper copies, for legal reasons.-- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●June 3, 20202020-06-03
On Wed, 3 Jun 2020 10:21:50 -0700 (PDT), Lasse Langwadt Christensen <langwadt@fonz.dk> wrote:>onsdag den 3. juni 2020 kl. 14.18.53 UTC+2 skrev jla...@highlandsniptechnology.com: >> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner >> <spamjunk@blueyonder.co.uk> wrote: >> >> >On 03/06/20 08:34, Ricketty C wrote: >> >> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >> >> about picking up really. It's about issues of multiple pages. They don't >> >> really support a flat, multi-page schematic. It must be hierarchical. So to >> >> have a two page schematic, you must have a top sheet and one or more lower >> >> sheets. >> > >> >As someone that hasn't used KiCad yet, but expects to soon, my >> >comment is "excellent" :) >> > >> >I have three peeves about many schematics that I see: >> > - principal signal flow in any random direction >> > - if a wire leaves one schematic, it isn't clear which >> > other schematic(s) is reappears on >> > - signal/bus wires that are named but not visually connected >> > >> >The latter really pisses me off, since on a PDF I have to >> >use ctrl-f to understand connectivity, and the schematic cannot >> >be usefully printed out. >> > >> >No, it isn't merely modern diagrams that do that, you also >> >find it in old Tek schematics. >> > >> >> I hate hierarchicals and busses and any abstraction that hides what's >> actually on the board. I do everything flat... currently a 31-page >> schematic with five basically identical output channels, each on its >> own sheet. I know exactly where R114 is. > >since it is R1xx on page 1After a PCB layout is done, we resequence the reference designators in the physical pattern that manufacturing and testing like, sort of raster scan from lower-left, and we back-annotate the schematic.> >> >> I do start a schematic with sheet 1 being the block diagram and sheet >> list/table of contents. Sheets have both numbers and names in the PADS >> pulldown menu. > >so whats the difference? I have a page 1 with a number of blocks and how >they are connected each of those blocks is a schematic.My block diagram is architectural and functional. If I did a sheet 1 as a hierarchical structure that actually created all the connections, it would be an unreadable nightmare. It is possible to more than one block point to the same schematic but it doesn't have to, each can>have its own so it just like your multipage schematic > >and if you print it you get all the pages even if some of them are the same except for designatorsSounds like complexity for its own sake. Many engineers like to do that, as opposed to just getting the job done. They come up with bizarre justifications for doing elaborate things. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●June 3, 20202020-06-03
On Wed, 3 Jun 2020 17:33:30 +0100, Tom Gardner <spamjunk@blueyonder.co.uk> wrote:>On 03/06/20 16:51, jlarkin@highlandsniptechnology.com wrote: >> On Wed, 3 Jun 2020 15:21:21 +0100, Tom Gardner >> <spamjunk@blueyonder.co.uk> wrote: >> >>> On 03/06/20 08:34, Ricketty C wrote: >>>> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >>>> about picking up really. It's about issues of multiple pages. They don't >>>> really support a flat, multi-page schematic. It must be hierarchical. So to >>>> have a two page schematic, you must have a top sheet and one or more lower >>>> sheets. >>>> >>>> The parts can have multiple units, but schematics can't have multiple pages. >>>> That seems oddly inconsistent. >>> >>> Another viewpoint is to consider the analogous situation in >>> large-scale software systems. >>> >>> For one person developing a small piece of code, nothing much >>> is needed. >>> >>> But in a large system that requires modification over the years, >>> it has been found necessary to develop techniques that have >>> the same characteristics as hierarchical hardware schematics. >>> >>> Example 1: all the various UML structural component diagrams. >>> >>> Example 2: the currently fashionable "inversion of control" >>> techniques. If you sit down and think about what they are >>> attempting to rectify, and how they are doing it, then you >>> see they are connecting stand-alone components and sub-components >>> in a hierarchy. > >I don't think you are aware of what's in medium and >large scale software.I am aware that a big program will have thousands of bugs in its lifetime, and may be remotely updated every month or so.> > >> A PCB is very different from code. Multiple copies have to be >> assembled my manufacturing, > >The similarities outweigh the differences.We don't prototype and expect rev A to be built by production, to released drawings, and we expect it to work and be shipped. The first release that we test, we expect to ship to a paying customer. Does anyone do software that way?> >Simple examples: operating systems, servers, server >applications. > > >> from purchased or fabricated parts. > >The similarities outweigh the differences. > >Simple examples: libraries, servers. > > >> Each board needs to be inspected and tested. > >The similarities outweigh the differences. > >Simple examples: one application installed in different >servers optionally in different companies. > > >> If changes must be made, they >> will be applied, per an ECO, to every board, by manufacturing. > >The similarities outweigh the differences. > >Simple examples: each application installed in each server. > > >> Field changes are physical and expensive. > >The similarities outweigh the differences.The similarities of that statement, six times, are tedious. Do you design electronics?> >Arguably it is more difficult to correctly change software.??? Hardware change requires releasing an ECO, getting physical access to the product, and doing mechanical things, then testing and calibrating.> > >> A computer program doesn't need many identical copies of a subroutine. >> A circuit board often does, but they usually wind up be not quite >> exactly identical. They are certainly physically distinct, even if >> they look alike on paper. > >The similarities outweigh the differences.Oh please. Repeating a thing N times doesn't make it true.> >Simple examples: objects, classes, and class hierarchies, >definitions of things such as "a person" or "the time". > > >> Computer programs don't need ground or power planes. > >Agreed, but so what! > > >> They should have >> test points and BIST, but they seldom do. > >No difference :( > > >> Very different. > >Nope.Do you design electronics? Schematics, pcb layouts, parts on boards? Few posters to s.e.d. actually do. Fewer are very good at it. -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
Reply by ●June 3, 20202020-06-03
onsdag den 3. juni 2020 kl. 22.11.44 UTC+2 skrev John Larkin:> On Wed, 3 Jun 2020 10:21:50 -0700 (PDT), Lasse Langwadt Christensen > <langwadt@fonz.dk> wrote: > > >onsdag den 3. juni 2020 kl. 14.18.53 UTC+2 skrev jla...@highlandsniptechnology.com: > >> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner > >> <spamjunk@blueyonder.co.uk> wrote: > >> > >> >On 03/06/20 08:34, Ricketty C wrote: > >> >> I guess I spoke too soon about KiCad being easy to pick up... well it isn't > >> >> about picking up really. It's about issues of multiple pages. They don't > >> >> really support a flat, multi-page schematic. It must be hierarchical. So to > >> >> have a two page schematic, you must have a top sheet and one or more lower > >> >> sheets. > >> > > >> >As someone that hasn't used KiCad yet, but expects to soon, my > >> >comment is "excellent" :) > >> > > >> >I have three peeves about many schematics that I see: > >> > - principal signal flow in any random direction > >> > - if a wire leaves one schematic, it isn't clear which > >> > other schematic(s) is reappears on > >> > - signal/bus wires that are named but not visually connected > >> > > >> >The latter really pisses me off, since on a PDF I have to > >> >use ctrl-f to understand connectivity, and the schematic cannot > >> >be usefully printed out. > >> > > >> >No, it isn't merely modern diagrams that do that, you also > >> >find it in old Tek schematics. > >> > > >> > >> I hate hierarchicals and busses and any abstraction that hides what's > >> actually on the board. I do everything flat... currently a 31-page > >> schematic with five basically identical output channels, each on its > >> own sheet. I know exactly where R114 is. > > > >since it is R1xx on page 1 > > After a PCB layout is done, we resequence the reference designators in > the physical pattern that manufacturing and testing like, sort of > raster scan from lower-left, and we back-annotate the schematic.it's all matter of preference, leave it like the schematic editor does it and you knnow what page it is and those components a around section of components have designators close together> > > > >> > >> I do start a schematic with sheet 1 being the block diagram and sheet > >> list/table of contents. Sheets have both numbers and names in the PADS > >> pulldown menu. > > > >so whats the difference? I have a page 1 with a number of blocks and how > >they are connected each of those blocks is a schematic. > > My block diagram is architectural and functional. If I did a sheet 1 > as a hierarchical structure that actually created all the connections, > it would be an unreadable nightmare. >how do you connect between pages then, global labels?> It is possible to more than one block point to the same schematic but > it doesn't have to, each can > >have its own so it just like your multipage schematic > > > >and if you print it you get all the pages even if some of them are the same except for designators > > Sounds like complexity for its own sake. Many engineers like to do > that, as opposed to just getting the job done. They come up with > bizarre justifications for doing elaborate things. >kettle black ;)
Reply by ●June 3, 20202020-06-03
On Wed, 3 Jun 2020 13:56:02 -0700 (PDT), Lasse Langwadt Christensen <langwadt@fonz.dk> wrote:>onsdag den 3. juni 2020 kl. 22.11.44 UTC+2 skrev John Larkin: >> On Wed, 3 Jun 2020 10:21:50 -0700 (PDT), Lasse Langwadt Christensen >> <langwadt@fonz.dk> wrote: >> >> >onsdag den 3. juni 2020 kl. 14.18.53 UTC+2 skrev jla...@highlandsniptechnology.com: >> >> On Wed, 3 Jun 2020 10:36:07 +0100, Tom Gardner >> >> <spamjunk@blueyonder.co.uk> wrote: >> >> >> >> >On 03/06/20 08:34, Ricketty C wrote: >> >> >> I guess I spoke too soon about KiCad being easy to pick up... well it isn't >> >> >> about picking up really. It's about issues of multiple pages. They don't >> >> >> really support a flat, multi-page schematic. It must be hierarchical. So to >> >> >> have a two page schematic, you must have a top sheet and one or more lower >> >> >> sheets. >> >> > >> >> >As someone that hasn't used KiCad yet, but expects to soon, my >> >> >comment is "excellent" :) >> >> > >> >> >I have three peeves about many schematics that I see: >> >> > - principal signal flow in any random direction >> >> > - if a wire leaves one schematic, it isn't clear which >> >> > other schematic(s) is reappears on >> >> > - signal/bus wires that are named but not visually connected >> >> > >> >> >The latter really pisses me off, since on a PDF I have to >> >> >use ctrl-f to understand connectivity, and the schematic cannot >> >> >be usefully printed out. >> >> > >> >> >No, it isn't merely modern diagrams that do that, you also >> >> >find it in old Tek schematics. >> >> > >> >> >> >> I hate hierarchicals and busses and any abstraction that hides what's >> >> actually on the board. I do everything flat... currently a 31-page >> >> schematic with five basically identical output channels, each on its >> >> own sheet. I know exactly where R114 is. >> > >> >since it is R1xx on page 1 >> >> After a PCB layout is done, we resequence the reference designators in >> the physical pattern that manufacturing and testing like, sort of >> raster scan from lower-left, and we back-annotate the schematic. > >it's all matter of preference, leave it like the schematic editor does it >and you knnow what page it is and those components a around section of components have designators close together > >> >> > >> >> >> >> I do start a schematic with sheet 1 being the block diagram and sheet >> >> list/table of contents. Sheets have both numbers and names in the PADS >> >> pulldown menu. >> > >> >so whats the difference? I have a page 1 with a number of blocks and how >> >they are connected each of those blocks is a schematic. >> >> My block diagram is architectural and functional. If I did a sheet 1 >> as a hierarchical structure that actually created all the connections, >> it would be an unreadable nightmare. >> > >how do you connect between pages then, global labels?Yes, we call them off-page connections, or just off-pages. Sometimes they connect on the same page. I recently connected the emitter of a transistor to a test point, using two off-pages immediately facing one another. That forced a net name that PADS would otherwise not handle the way I want. The test point is only there as a way to drill down to a layer-5 copper pour used as a guard.> >> It is possible to more than one block point to the same schematic but >> it doesn't have to, each can >> >have its own so it just like your multipage schematic >> > >> >and if you print it you get all the pages even if some of them are the same except for designators >> >> Sounds like complexity for its own sake. Many engineers like to do >> that, as opposed to just getting the job done. They come up with >> bizarre justifications for doing elaborate things. >> > >kettle black ;)Board blue! -- John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com
