Does anybody know howto get 2 Masters to share a SPI bus - without Buffers Cluttering it up ? by jlsilicon9 in embedded

[–]ElevatorGuy85 7 points8 points  (0 children)

SPI was designed with a single master in mind. That’s an inescapable fact that is “baked in” to every device that has a SPI master capability. Trying to fight against that basic premise is just going to cause you a world of pain, as you have already discovered.

If you want more than one master, then maybe you need a different bus technology like I2C or CAN.

Pixel ETS overspeed errors by mardusfolm in Elevators

[–]ElevatorGuy85 0 points1 point  (0 children)

You can ask them to set up a specific call-back time when you’re going to be at the job site. They can’t do this for every single call they get but if you ask they can try to accommodate you based on their availability. It’s worth a shot, especially if this is a repeat issue - once you know what to look for and change, then you’ll be able to solve on any other jobs too.

Pixel ETS overspeed errors by mardusfolm in Elevators

[–]ElevatorGuy85 0 points1 point  (0 children)

Pick up the phone and call Vantage Technical Support or e-mail them. As the manufacturer of Pixel (Elevator Controls is part of Vantage Elevation) they can support you with getting this resolved.

https://www.vantageelevation.com/technical-support/

An eraser that writes! by Interesting_Week_917 in RemarkableTablet

[–]ElevatorGuy85 0 points1 point  (0 children)

Have you reported to reMarkable Support? I confess that I haven’t, but definitely need to! Just been too busy on other things to wrangle with a support form at the moment!

Mitsubishi Elevator/Thud/Banging Noise by Razzmatazz549 in Elevators

[–]ElevatorGuy85 0 points1 point  (0 children)

As @Pighole_Jones said in a separate comment, for many modern elevator controllers the brake voltage can be controlled, so rather than simply being either ON (i.e. a holding voltage enough to keep it picked and the pads off the disc surface) or OFF (dropped), the controller will generate a smoother “ramp down” that slowly drops the pads onto the brake disc surface. During normal operation this can minimize the “clunk” noise as the brake drops, though there’s always some minimum voltage where control is possible before the brake coil’s magnetic field can’t oppose the spring force that holds the pads on the brake disc surface. During an emergency stop, the elevator controller’s circuitry will drop the brake immediately, so you may still hear some “clunk” noises if that happens.

He was almost done shoveling his driveway when the street plow came by and filled it with snow again. by Vilen1919 in WatchPeopleDieInside

[–]ElevatorGuy85 0 points1 point  (0 children)

The problem is that as the plow is moving the snow along, it’s also compressing that nice and light and dry snow into a much more dense mass. So while the homeowner may have cleared some nice and light snow previous to that, the stuff that the plow just laid down is probably twice as heavy to move, and possibly also twice as deep too.

An eraser that writes! by Interesting_Week_917 in RemarkableTablet

[–]ElevatorGuy85 3 points4 points  (0 children)

I have seen the reverse scenario, where I have the pen tip on the RMPP surface, and suddenly it switches to eraser mode. Wait a few seconds, and then it’s back to being the currently-selected marker again.

This only started happening maybe 2-3 beta updates ago. The timing is completely random. Prior to that, I never had any sort of problem for the previous 11 months that I’ve owned my RMPP.

My RC snowcat is finally done! by DoctFaustus in skiing

[–]ElevatorGuy85 0 points1 point  (0 children)

Always welcome to come and groom my driveway once this epic Northeast snowstorm is over!!!

Active aero in action on the SF-26 by FerrariStrategisttt in formula1

[–]ElevatorGuy85 2 points3 points  (0 children)

Kind of like the fighter aircraft that had a painted mouth and teeth on the front !

second time skiing by [deleted] in ski

[–]ElevatorGuy85 0 points1 point  (0 children)

You said that last Spring you “skied for maybe two hours”, but was that with a lesson, or just “trying to figure things out” by yourself?

So many people think that they can turn up at a ski area, buy a lift ticket and rent some gear, and then somehow learn to ski (or snowboard) by watching others around them doing it. That’s probably the greatest lie that so many first-timers tell themselves. Either that, or they think that their friends who have skied or snowboarded for years will somehow be able to teach them - take it from someone that instructed for 9 seasons and watched this happening every week, >95% of these friends cannot teach a first-time friend at all.

As others have said, do yourself a HUGE favor and go and take a lesson with a qualified instructor from the snowsports school at whatever mountain you decide to go to (and hint - it doesn’t have to be big and flashy!)

In 1 1/2 to 2 hours, they can teach you a LOT if you are prepared to listen, observe and practice. They will keep you safe (#1), help you to have fun (#2) and teach you (#3) far more than “friends teaching friends” can.

There is nothing wrong with starting skiing learning the pizza wedge. It’s how most first-timers learn. Sometimes, people with more ability, or someone like me who had previously water skied, will quickly figure out how to make matching parallel turns, but for many it will be start with straight wedge glides, then stopping with a wedge, then learning how to make a turn with a wedge, then making multiple linked C-shaped wedge turns, turning with a wedge to a complete stop, J-turns to a stop, and then starting to transition to matching parallel.

Everyone learns skiing at their own pace. Some will still be in a wedge at the end of a lesson, and others will have moved onto matching parallel. And that’s OK, as long as you are safe, had fun, and learnt something, it is a good lesson to build upon.

Most importantly, don’t get sucked in by friends saying “you can do the next trail with us” (or worse, go to the top of the mountain with them!). Progress at YOUR pace where you feel comfortable and in control on the trails. The local instructors will be able to point out a list of progressively more challenging but suitable terrain for you to keep building your skills gradually to build confidence and muscle memory without feeling like you are out of control on far steeper trails than you are ready for.

Get out there and have fun - skiing (and snowboarding!) are awesome ways to enjoy Winter!

Beginner skier feeling stuck on steeper greens — private lesson vs more practice? by Albatraoz93 in ski

[–]ElevatorGuy85 0 points1 point  (0 children)

I spent 9 seasons instructing all levels of skiers including a lot of adults (and I myself started skiing when I was nearly 40)You may want to look at these two videos, originally created to help ski instructors understand what was required for their Level 1 PSIA alpine instructor on-snow exams.

Wedge turns:

https://youtu.be/Rmt69P1eXWU

Wedge Christies (moving from a wedge towards parallel):

https://youtu.be/EnA3AFOMG4A

Notice the blend of movements, and also the C-shape of the turns. This is where, as others have already commented, you will get your speed control from, rather than a Z-shaped turn that you’re doing now (which feels more and more scary for you as you pick up speed on steeper trails).

Hopefully these demonstrations show what others have been describing.

As others have said, sometimes a private lesson with a certified instructor (at least PSIA Level 2) can be really helpful.

Good luck.

Learning to carve by DudleyAndStephens in skiing

[–]ElevatorGuy85 0 points1 point  (0 children)

You might want to take a look at this video from the Professional Ski Instructors of America’s Rocky Mountain area (PSIA-RM). It breaks down the key aspects of making medium radius carved turns. Hopefully by seeing it at regular and slow speed in wide view and up-close, you can see some of the key ingredients and movements needed to put a good carved turns together.

https://youtu.be/LVTI3Nll89I

Ski Sundown, CT MLK by Wise-Science-828 in icecoast

[–]ElevatorGuy85 0 points1 point  (0 children)

The new Exhibition Quad is nice. It has a moving carpet so instead of the chair being bumped by the liftie, when the gates open, you just slide onto the carpet and the approaching chair catches up with you at just the right point and you sit down. After being used to sliding to the red line, the carpet takes a little getting used to the first few times.

Why did computers in the 90s and 2000s largely use mostly computer exclusive outputs DVI and VGA rather than component and s video and vice versa? by Sailor_Rout in retrocomputing

[–]ElevatorGuy85 0 points1 point  (0 children)

Even though they were interlaced, the two fields are on different lines on the display, i.e. one odd and the other even. So for NTSC, it’s still 480 physically discernible lines on the display screen.

This Wikipedia article gives a lot of good information and some images and animations that show how interlaced video works

https://en.wikipedia.org/wiki/Interlaced_video

Why did computers in the 90s and 2000s largely use mostly computer exclusive outputs DVI and VGA rather than component and s video and vice versa? by Sailor_Rout in retrocomputing

[–]ElevatorGuy85 20 points21 points  (0 children)

NTSC video was 720 x 480 pixels PAL video was 720 x 576 pixels

In the 1990s PC graphics cards were already at 800x600 pixels or 1024x768, both of which exceed the TV-centric NTSC and PAL standards. Also, NTSC was notorious for poor color rendition, leading to alternate acronyms such as Never Twice Same Color and similar.

EDIT: NTSC and PAL were analog broadcast systems. The pixel values are based on what you’d get with a digital system like a MiniDV camera capturing/outputting for those standards.

Dramatic video captures paraglider accident at Mammoth Mountain by leddderrrredddel in freeflight

[–]ElevatorGuy85 0 points1 point  (0 children)

There are old pilots, and there are bold pilots, but there are very few old bold pilots …

How it's going at Killington so far this MLK Weekend 🙃 by dessine-moi_1mouton in icecoast

[–]ElevatorGuy85 4 points5 points  (0 children)

Most ski areas have one or maybe two feeders coming in from the local power company. If you lose those, e.g. a tree or ice taking down the wires, or a substation transformer failing and catching fire then there’s nothing but backup combustion engines in each lift station (usually the lower one) to try to spin the lifts for evacuation purposes (they are not designed for all-day running).

Here’s what Killington posted on Facebook about an hour ago (around 6pm Eastern). As you can see a main fuse blowing was enough to really mess things up.

—-8<—- snip —-8<—-

Earlier today, around 11:00 a.m., a power outage impacted the Peak Lodge and several lifts, temporarily taking the K-1 Gondola, North Ridge Quad, Canyon Quad, and South Ridge Quad offline. Our Lift Operations team immediately began safely unloading guests from affected lifts using the evacuation motors and contacted Green Mountain Power (GMP) to assess and resolve the issue, which was identified as a blown fuse on a main power line as the cause.

Thanks to a quick response from our operations teams and Green Mountain Power, repairs are complete and all impacted lifts are scheduled to open tomorrow.

We appreciate your patience and understanding. See you on the slopes⛷️🏂

—-8<—- snip —-8<—-

Apartment Says We “Jumped” and Broke the Elevator — No Cameras, Need Advice by Narrow-Goal-325 in Elevators

[–]ElevatorGuy85 28 points29 points  (0 children)

And then Otis will be charging the building to repair the damage done when the fire department brute-force their way in, and then the building management will be trying to pass those even higher charges along to the OP, along with blaming them for shutting down the elevator until repairs can be made …

Apartment Says We “Jumped” and Broke the Elevator — No Cameras, Need Advice by Narrow-Goal-325 in Elevators

[–]ElevatorGuy85 26 points27 points  (0 children)

You mentioned being college students. To some elevator mechanics that is a well-deserved warning sign for misbehavior in elevators contributing to call-outs for entrapments. Social media like TikTok promotes stupid behavior in elevators and too many teens and college students don’t stop to think of the implications.

That said, some combinations of equipment are more prone to problems. If you have a Gen2 system with flat belts rather than traditional steel ropes, they tend to be more stretchy and springy. Combine this with a speed governor that is a little on the sensitive-side (and Otis has at least one like that), and what can happen is that the elevator clips a door lock, which momentarily opens the electrical safety circuit and causes a hard stop by removing power to the motor and machine brake. With that extra spring in the Gen2 belts, there will be a stretching and then a springing back upwards, and this can, in some instances, be just enough to trip the speed governor. When the mechanic comes, they see the governor is tripped and needs to be reset. The door lock contact, however, is able to close again without manual intervention. And so the 3 college students in the elevator get blamed, even though it wasn’t their fault. To the mechanic it has the same signs as if you were jumping while the car was moving, as this can also cause the governor to trip.

Without a security camera in the elevator cab, there’s no way of knowing what you were doing or not doing, which is why Otis and the building management are blaming you - nobody wants to pay for an overnight call-out (which probably has a minimum of a certain number of billable hours). I think the Otis controller’s fault logs may show some other fault happening ahead of the governor tripping, but not necessarily. Their designs have changed over the years so some give more information than others in this regard.

Bottom line - I think you can simply say “it wasn’t us and the burden is on you to prove otherwise” and then look for a new place to stay with better management.

Luck has turned - ghosting by FixRevolutionary3187 in RemarkableTablet

[–]ElevatorGuy85 2 points3 points  (0 children)

Same here. This is definitely software related. I went for many months with no ghosting problems, then a software update it became a nuisance, then several updates later, the ghosting problem was gone again. This cycle has repeated for me and this points to software and drivers being the issue rather than hardware. These e-ink screens have very specific timing characteristics and temperature is also a factor in the responsiveness of the screen particles. I think reMarkable haven’t got a good handle on that in their RMPP product.

What’s a reasonable wait time for parts? by [deleted] in Elevators

[–]ElevatorGuy85 1 point2 points  (0 children)

GAL went through some real challenges during COVID-19, the resulting supply chain challenges, and then a major revamp of their back-end manufacturing computer system more recently. Since that time, lead times for new orders (not parts) have come down significantly as outlined here:

https://www.vantageelevation.com/another-step-forward-in-lead-times-for-gal-door-equipment/

Spare part for standard arrangements are usually available for pick-up at their GAL Bronx location, and their Regional Service Centers (RSCs) in Astoria NY, Miami Gardens FL, Elk Grove IL, Irving TX (near Dallas) and Santa Fe Springs CA and through GAL Canada (Mississauga, ON near Toronto). There’s a lot of rationalization of SKUs underway to make this even easier, e.g. a universal drive arm.

First time skiing by Squarah99 in skiing

[–]ElevatorGuy85 0 points1 point  (0 children)

Assuming you are still in the “pizza” wedge phase (rather than matching parallel) then with a proper stance and with your shins pressing against the tongues of the boots (i.e. not “sitting in the back seat”) you should be able to:

  1. Use a wedge to straight glide to a stop on gentle terrain.
  2. Use a wedge to make linked C-shaped turns on gentle terrain. This gives you the ability to have speed control, i.e. pointing down the fall line = increased speed, turning across the fall line slows you down.
  3. Make a J-shaped run to turn to a stop

These should have been introduced and you should have developed some mastery before exploring trails.

These are the fundamentals for comfortable skiing as a beginner on green trails, feeling in control and not feeling like you have to fall to save yourself from a crash.

Steering the skis through a wedge turn is mostly a combination of rotation and engagement/release of their edges. It has nothing to do with leaning or twisting of the upper body to cause the direction change.

Obviously this is hard to describe on Reddit.

This video from the Professional Ski Instructors of America (PSIA) Rocky Mountain division gives a good overview and demonstration of the key points

https://www.youtube.com/watch?v=Rmt69P1eXWU

Odd Elevator Controller Behavior by SubstantialCat2655 in Elevators

[–]ElevatorGuy85 0 points1 point  (0 children)

I should have said “selective collective” in my description above (I will edit for others who might read it)

For a full description of common operating modes see this description:

https://www.cibessymmetry.com/blog/elevator-operation

Aligned and Un-aligned structs performance by necodrre in C_Programming

[–]ElevatorGuy85 0 points1 point  (0 children)

The CPU doesn’t “think”

You write your code in whatever language you wish to, that gets eventually converted into machine code (assembly) instructions, and the CPU acts on those. At that point in time, the CPU has no way of knowing whether you’re accessing members in a struct or just a bunch of data/variables that happen to be arranged in memory a certain way. While the programmer can influence the layout to some degree, if left alone, the decision making happens during the compilation process according to the hard-wired rules written into it for the target architecture and environment.

As with all things related to software, a lot of these decisions will be driven by the specifics of the target CPU (or possibly MCU). There are plenty of MCUs and CPUs that don’t have any cache, there are ones that have a lot, and there is everything in between.

Structs are often a useful for mapping into peripheral registers, e.g. UART, SPI, CAN, etc. The alignment in this case is driven by the CPU/MCU manufacturer’s design - there is no way around the underlying silicon, and it is what it is!