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What if your mentor does not know the answer to your question?
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tggzzz:

--- Quote from: pcprogrammer on September 21, 2022, 04:48:27 am ---
--- Quote from: temperance on September 20, 2022, 07:00:55 pm ---Today many people seem to think labeled net's are the proper way to draw schematics. Your mentor could have give you some advise on drawing proper schematics.

--- End quote ---

For very big parts like FPGA's or ADC's with lots of pins it is very difficult to not do it without labeled nets. Even when connections are made with buses it is still needed to label the unique signals. And only for printed to paper it makes a difference in reading the schematic. On the computer it is easy to use the tools like find to find the connected pins.

With these big parts it is often needed to use multiple sheets and then the only way to connect is via labeled nets.

In the end nowadays the schematic is mainly part of the toolchain for the engineer to get to the PCB. And here the computer makes net lists to check if both schematic and PCB are the same. No manual checking needed.

But I agree that for simple schematics using wires to make the connections makes it easier to read.

--- End quote ---

Not true: there is a halfway house that has been in use since the 1970, i.e. before CAD was common. The halfway house is to use a bus, which combines the best of both techniques. Put simply, many "wires" are collected together and individual wires labelled where they enter/exit. That's a no-brainer for data and address busses, but also works well for control busses and (less usefully) for power supplies.

With software designs, "coupling" and "cohesion" are considered to be key metrics of quality. They are just as important in hardware designs.

Wires and busses directly show cohesion and coupling. Labelled nets explicitly hide cohesion and coupling.
pcprogrammer:

--- Quote from: tggzzz on September 21, 2022, 10:50:02 am ---Wires and busses directly show cohesion and coupling. Labelled nets explicitly hide cohesion and coupling.

--- End quote ---

Yes that is true, but then there is still the need to lookup a specific signal on both ends of the bus, and when the bus spreads multiple components or sheets it is still the trick to find the signal on the other end.

But another matter in schematics drawings nowadays, also used by me because I got somewhat lazy, is black box symbols for basic logic components or even opamps. You know, just a simple square, the part number and the connections, without a clue as to what is inside the black box. Sometimes even a whole 7400 ic instead of the single 2 input and gates. :palm:
tggzzz:

--- Quote from: pcprogrammer on September 21, 2022, 11:26:15 am ---
--- Quote from: tggzzz on September 21, 2022, 10:50:02 am ---Wires and busses directly show cohesion and coupling. Labelled nets explicitly hide cohesion and coupling.

--- End quote ---

Yes that is true, but then there is still the need to lookup a specific signal on both ends of the bus, and when the bus spreads multiple components or sheets it is still the trick to find the signal on the other end.

But another matter in schematics drawings nowadays, also used by me because I got somewhat lazy, is black box symbols for basic logic components or even opamps. You know, just a simple square, the part number and the connections, without a clue as to what is inside the black box. Sometimes even a whole 7400 ic instead of the single 2 input and gates. :palm:

--- End quote ---

Or signals going right to left. Feedback signals ought to be shown right to left, of course  :)

Or ignoring traditional schematic layouts, designed to give a Big Hint about what that part of the circuit is doing.

Or cramming everything onto one sheet, distorting the schematic layout. (Win Hill and Bob Pease are offenders there :( )
temperance:
pcprogrammer,

did I say net labels should be banned from your vocabulary to develop readable schematics? The other extreme is not using net labels and buses at all which is equally bad. Examples of both can be found everywhere while rules to create readable schematics aren't that difficult to apply with reason.
pcprogrammer:
 :-DD :-DD bdunham7 is right we are a bunch of grumpy old men  :-DD :-DD

https://www.eevblog.com/forum/chat/important-poll-should-there-be-an-off-topic-section/msg4407187/#msg4407187
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