On 2013 Jul 28, at 11:19 AM, Tony Duell wrote:
I take the position that the primary point of a schematic is to
elucidate the functional, electronic organisation of the device. The
OK,. That is certianly one important use. I don;t think it's the only
one, but...
Hang on a second... If you primarily want to see how the thing works,
then why do you care about the pin numbering of inputs on gates. The
reaon the pins all look the smae on the schematic is that they act the
same -- you can wswap round the inputs to an AND, NAND, etc gate
and the
circuit does the same thing. So not knowing my convnetion shouldn't
matter here.
If we piece back together my sentence you split, it says:
The physical implementation is important, but a secondary
consideration.
I didn't say the physical details were irrelevant or to be discarded
(from the schematic).
> physical implementation is important, but a
secondary consideration.
> For somebody repairing a unit, which they are probably doing on a
> one-
> off instance for an RE'd item, the first priority is still that
> functional understanding.
...
If you want
all the physical associations as close together as
possible, prioritised over the functional, it becomes a wiring
diagram.
I feel the same schemaitc can be used for both. That is, by
adopting IC
diagram conventions or numbering the pins, by drawing out
connectors, by
putting descriptions of the colours of the wires, etc the same diagram
cna both be a functiuonal diagram and a a wiring diagram
Yes, it can be used for both, as I indicated in my sentences you
snipped:
The physical implementation is still present and recorded in full
in the form of
IC pin numbers and connector pins along signal lines, and there
are pages with
all the connectors pins laid out if one wants to go from the
physical to the functional.
But I've certainly seen wiring diagrams where figuring out the
functional is torturous. The machine itself can be used for a
functional understanding of how it works but it usually becomes
pretty awkward.
It's what one chooses to prioritise in the representation
(schematic), which is not the same as relevance/irrelevance.
(The pages you
are looking at are old, it has since been encapsulated
in a single PDF, updated now.)
OK. I couldn't find this PDF anywhere, it is on the web?
It's on my AL-1000 page.