Dot allowed as characters allowed in netlist?

Funny, this from the same guy who earlier told of the 0..15 vs 15..0 bus naming scheme. Properly named buses don't rename themselves, either.

Thing is, people do mess up. Communications is sloppy at times. Notations that make misunderstandings harder are better. Nobody proposes to replace all decimal points with units and multipliers, but for standard parts with standard values it does make sense.

I'm all with you on the aesthetics side of things, and I also am convinced that aesthetics is important even (or especially?) in technical communications. Sometimes aesthetics does havt to take a back seat though.

robert

Well, you have a pin, and you're assigning a net name. It /is/ a netlist, in graphics rather than flat text!

Why would anyone draw it differently?

Well, aside from the nonsense DQ ordering. Which I might assume was done for layout, permuting any command words in software as needed.

The big black bus notation is nice for showing block-level interconnectivity, but that's almost completely irrelevant unless you are still using E size sheets somehow. Hierarchical design shows that better anyway; the top sheet doubles as your block diagram ("self-documenting code"?).

Tim

--
Seven Transistor Labs, LLC 
Electrical Engineering Consultation and Contract Design 
Website: https://www.seventransistorlabs.com/

It was a sketch and I guess mil in the UK was meant to be millimeters.

--
Regards, Joerg 

http://www.analogconsultants.com/

It's not a clinging of any sort. It's just that we are used to it. Besides, if you study some documents from Airbus Industries you will find ... imperial units.

After living in the US for decades I became so used to it that the switch to metric on the current assignment felt a bit unusual (a US client wants everything metric). The next one is going to be aerospace where things are imperial, even overseas. Similar in the kitchen or when brewing beer where we measure everything in pounds, ounces, teaspoons and so on. When a European asks us for a recipe we have to first re-calculate everything.

--
Regards, Joerg 

http://www.analogconsultants.com/

Sometimes it is of advantage to lock up the brakes. Example: I blew past a turn-off on my mountain bike. Saw a big rock pile coming up, fast. There was a lot of gravel so I locked up both wheels (yes, also the front but only modestly), the bike's wheels dug in and it stopped very quickly. If I had been on a bike with anti-lock brakes such as some "modern" motorcycles have I'd have crashed face first into that pile of rocks.

Snow and ice are other examples where I would not want to have anti-lock brakes.

--
Regards, Joerg 

http://www.analogconsultants.com/

British influence. Imperial.

I hate that. Also makes scaling recipes more of a hassle. I have a cookbook that wants me to reduce a sauce that consists of little more than the contents of a 28oz can of tomatoes (basically water) to "about four cups". This sort of mistake doesn't go unnoticed in the metric system. Yes, I checked if American canned tomatoes go by their net weight, not including the juice they're packed in. They don't.

robert

Things like RAMs are just boring boxes sprouting pins. Analog schematics can have style and sometimes beauty.

We let our layout guy scramble pins to make the routing better. Then we compile the FPGA pinout to match. In this case, there was no software butchering needed.

This worked first try, the whole 10-layer board, with a couple of minor tweaks, like the 1K resistor to the right of the DRAM, some weirdness about FPGA configuration. Rev A is perfectly sellable:

When it loaded Linux from the SD card, and ran the DRAM diagnostic, I was sure relieved.

Sheet 1 of our schematics is always a block diagram and table of contents for the other sheets.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

It would be a serious blunder to machine something off size by a factor of 40. And to machine something based on verbal descriptions.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

We use SI units for calculations but decimal inches for mechanical designs and PCB layout.

We have some aerospace customers who use old units (lbs, lbf, slugs, feet and inches, BTUs and associated horror thermal units) to design airplane engines. THAT is insane.

Pounds, feet, gallons, miles/hour, degrees F, all that stuff works fine in real life for most people.

Gas is cheap here, since we get a gallon for what Europeans pay for a liter.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

That was a mistake that a former engineer made about 20 years ago. We learn from mistakes and try not to repeat them.

And the format was ADDR[15:0], not [15..0]

I wonder how the 4K7 notation started. Does anyone know? The first time I saw it was in some amateur electronics magazine. I see it mostly in audio stuff. I have never seen a "serious" electronic designer do that.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Verbal stuff happens all the time, especially when hard up against a deadline. I remember when it was 1am at a client, the flight for the engineer and the prototype system to a trade show was scheduled for 6am and the system was not operational. We were in and out of the machine shop, no drawings, just hollering instructions down the hallway. We made that flight.

--
Regards, Joerg 

http://www.analogconsultants.com/

No. I disagree completely. Modern anti blocking systems re-evaluate the blocking in less than 2 inches. It is pure hubris if one thinks one could do better. Anti blocking systems are really not so much about minimizing the way to halt but to keep the bike controllable. It is one thing when your front tire crashes into a rock or when your spine crashes into the rock because you suffered a picture book highsider for overstressing Kamm's circle.

I have done several trainings at the BMW offroad school in Hechlingen, Bavaria <

> and since the ABS can be switched off, we were invited to give it a try. No one of the participants, including the instructors was better than the system. We did that on gravel and dirt with a starting speed of 70 Km/h.

We were kindly asked to limit the experiments to the back wheel, because when the front wheel goes hiwire, the game is over. You are airborne in milliseconds.

Unfortunately, the biggest part of the braking effect comes from the front wheel because it carries more weight during braking, while the back wheel is unloaded.

So, for a short stopping distance, you MUST maximize the use of the front brake, but definitely without blocking.

The ABS control switch belongs to the ON position. And then keep the brakes _fully_ engaged.

regards, Gerhard.

Den torsdag den 15. marts 2018 kl. 16.51.06 UTC+1 skrev John Larkin:

apparently British Standards Institute in 1975

Buses using the big black lines are very useful when designing large fast digital systems. In my case those were mostly ultrasound where you had umpteen digital chips per board, typically multipliers, filter chips, processors, DSP, RAM, FIFOs and so on. Signal flow was often in excess of 100 MBytes/sec. There were more than a dozen chips per sheet. Sheets higher up in the hierarchy had a dozen or more blocks, all bused. Doing all that netlist-style can quickly make it difficult for others to understand how the circuitry operates.

--
Regards, Joerg 

http://www.analogconsultants.com/

No, it's aerospace. Things are imperial in that domain except for Russia and some countries with close links to there.

Maybe they meant four sippy-cups :-)

--
Regards, Joerg 

http://www.analogconsultants.com/

If they wanted millimeters they should have sketched "mm".

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

Yeah, I think Nuts and Volts was the first place I saw that.

--

John Larkin         Highland Technology, Inc 
picosecond timing   precision measurement  

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

I agree, you haven't sat next to me whilst I do 100,000s of sims a year using SS...

Now, if only Cadence Virtuoso did it as well...

-- Kevin Aylward

- SuperSpice

I know I can. Of course not always but in many situations. I do not want some computer to make that decision for me.

They did not teach you the brake slide? Seriously?

Try this with anti-lock brakes:

Look at the rear wheel here:

Now I do not condone shredding trails using that riding style but in an emergency one has to often lock up the rear wheel. Especially when finding out that a downhill section was steeper than anticipated or after having entered it at too much speed. Locking up a wheel has saved the bacon for me more than once.

Even dirt bikers do that:

It isn't. I've gone way behind the seat of my mountain bike many times to be able to not go over the handlebar even when pulsing the front wheel into lock-ups. Granted, that maneuver is typically only needed after a rider screw-up such as excessive speed but that stuff happens.

Nope.

Sometimes you have to be able to get it to slightly dig in and that only works with partial blocking (wheel rolls slower than vehicle speed) or by pulsing it. On the rear it can mean completely locking it up.

The last time I rode a long narrow road in the mountains on snow with ice underneath I often locked up the front wheel. It was a fat bike with

4" wide tires. Locking allowed snow to pile a bit in front of the front wheel and sometimes was the only way to slow down, aside from laying the bike which is a highly undesirable maneuver.

However, you've got to instinctively go low and behind the seat, IOW belly-ride the bike. That is what even seasoned Tour de France riders do wrong in an emergency because they haven't developed this sort of muscle memory. It only comes after thousands of miles of off-road practice.

On a mountain bike that can result in a nasty crash or worst case going over a cliff.

BTW, this is one of the trails around here. Though I use a mountain bike, no motorcycle:

--
Regards, Joerg 

http://www.analogconsultants.com/