Interesting that it uses a PIC processor. I had an American Standard (Trane) heatpump installed at my current house. I noticed once winter came that the defrost cycles just didn't seem to be working right. They are supposed to be "on demand" but were occurring at every 30 minutes of accumulated runtime once outside temps dropped below 32 degrees. Noticed the defrost controller board had a PIC processor on it... Got the pickit3 rom flasher/reader and was able to read the rom. It didn't have any code protection thankfully. I ran the exported hex through gputils to disassemble it, and then ran it in the mplab simulator. I could tell it was hand written assembly. It used hardcoded values in some areas to set the program counter (vs just using goto and lables) so that made modifying the code harder (since you would need to then find all these hard coded values and offset them).
Long story short, the fireware was indeed full of bugs. It is possible that these controller boards haven't been working right for the last 10+ years. I managed to add a few lines of code to bypass some initial values when the board is first powered up, and that fixed the issues. It is indeed an "on demand" defrost controller now. I'm still slowly writing a blog post about it but probably won't get more time to publish for a few months.
But I guess the point is, after messing with this, there seems to be an entire world of embedded firmwares that are just riddled with bugs and will never be fixed.
gputils did an amazing job on the disassembling! There are labels, gotos and functions all laid out. Hardcoded and calculated values were added to the PC in many places like: "addwf PCL, F" In that case, add W register into PCL, and store value into PCL.
Trane had the original patent for computer controlled defrost: https://patents.google.com/patent/US4573326A/en In the first image you'll see a chart with different temperature "bin" factors. In one place in the code, the temperature offset from 32 degrees (freezing) is added to a hardcoded value and the PC then jumps into a certain spot in a lookup table. The values in that lookup table help determine at what "DT" (delta temp between outdoor coil and outdoor ambient) a defrost should initiate. In another location, a hardcoded value is added to the PC along with a loop counter.... On loop 1 through the code, jump to this location, on loop 2 jump to this location, etc. Kind of a strange way to code, but after buying different revisions on ebay of this board going all the way back to the early 2000's, and on top of the patent being from 1985, perhaps this was the norm in the 80's and mid 90's.
I’ll be very interested to read your work on the Trane heat pump firmware. If you finally find the time, please, send me an email so I could add your article to the newsletter embedsys@embedsysweekly.com
Author here. I'm honored to see someone actually posted this on HN. :)
I purchase my Dyson V7 as an official refurb and the battery went in to lockout a few months after the short refurb warranty expired. Thus prompting the project. The vacuum is pretty handy for my small apartment, and when I bought it, I wanted something that had decent reviews and was from a real company, not just some Amazon seller with a bunch of random characters for a name. I still like the vacuum, I just wish Dyson hadn't designed it to fail.
I think there are two issues here:
1) The left out the cell balancing circuitry which is pretty standard for battery packs.
2) They designed their firmware to go in to permanent lockout when the cells go to far out of balance (300mV).
For the sake of discussion, I've heard interesting two arguments on why they might have disabled cell balancing:
1) Cell balancing could be a weak point on the ISL94208 IC they used, so they could have disabled cell balancing to actually increase overall reliability. We'd never know for sure, but I could see this being plausible. This is from someone on the EEVblog thread (https://www.eevblog.com/forum/projects/fu-dyson-bms-an-(unof...)
2) Cell balancing isn't actually useful because a poor battery cell will plummet in voltage under load anyways due to the higher ESR in the poor cell. At least, that was my interpretation of their argument after translating it from Russian to English in a comment on the YouTube video. While I see their point, especially in the vacuum's turbo mode which draws 17A vs the usual 3A, I think there would still be some usable capacity to be gained by balancing the cells even if one did have a much higher ESR.
Meta: I interpreted the "FU-Dyson..." in the project as "F*uck you Dyson", not "Firmware upgrade", did I make the right interpretation? :)
Also, this resembles why I'm very reluctant to buying an e-scooter in Sweden since basically all the ones available here are rebranded OEM Alibaba scooters with poor/fake battery implementations, so when it fails you'll be standing there with no way to get back on the saddle again.
Even the Swedish-branded Vessla scooters were rebranded OEMs from Alibaba, with minor cosmetic changes and a hefty premium. After a while the batteries turned out to be of poor quality, and after their v2, they quit that vertical entirely.
Looking forward to Segway launching their e-scooters in Sweden, at least I know it's a reputable brand standing behind it and can honor warranties etc. I want something quite small that I can have in the apartment (theft and vandalism otherwise), and can use to scoot my kid to school with.
Good man, I hate Dyson shit so much. It's all overpriced rubbish. Whenever I see their hand-dryers in a public bathroom I just use paper towels instead because they tend to blow stagnant water and particles in your face.
> Whenever I see their hand-dryers in a public bathroom I just use paper towels
Removing and replacing paper towels with hand dryers in public bathrooms has been an unfortunately shortsighted move that's been copied without much thought. Hands aren't the only thing that get wet in a public bathroom. You may wash your face, you may be removing stuff off your clothing, and countless other uses that a hand dryer alone can't accommodate.
Those directional nozzle hand dryers that twist upwards so you can dry your face is a big billy bonus. One of my favourite campsites set in the Welsh Mountains has a Dyson blade for drying hands, and sure its very quick to dry your hands, but on a freezing winters day or night coming back from a hike in the mountains and its freezing cold and you are soaked through, the directional nozzle hand dryers give you that warmth you can never get from the Dyson blade, like drying the insides of your hiking boots for the next morning.
The ultimate bachelor's vacuum cleaner was the Dyson DC15 Animal. It just cleaned and cleaned and cleaned, their newer stuff I dont rate.
I grew up with a Miele vacuum cleaner (my parents were all about Miele). Only disadvantage is they last so long that newer hardware is potentially more energy efficient. I don't get the point of wireless vacuum cleaner except autonomic ones and in niches where you don't have electricity (like an area where the electricity is often down). Having recently owned some different brands (Samsung, Beko) which broke down got us back te Miele again.
Have you ever used a wireless vacuum? It may sound stupid, but it saves significant time and effort over a conventional vacuum; taking the clunky vacuum out, plugging it in, unplugging it and putting it back means it takes (much) more than twice as long to do spot vacuuming.
Personally I'm never going back to a corded vacuum if I can avoid it.
> I don't get the point of wireless vacuum cleaner
The point of anything cordless is how it eliminates the hassle of, well, dealing with cords. In case of a vacuum cleaner, one has to:
- pull the cord out
- plug and re-plug it
- ensure it doesn't get stuck around the corners and under furniture legs
- ensure it doesn't pull some other furniture and topple them over
In addition, corded vacuums have practically no power envelope or weight restrictions, so they end up being bulky, heavy and loud, even if the context in which they are used doesn't require the power.
Dyson cordless (I can't speak to any other) in contrast:
- weighs lot less and can be carried around with ease
- can be moved around without a second thought of where the cord is or whether it can be maneuvered in a certain way
- is a lot quieter (can be used at night)
- is instantly accessible without any setup so it makes sense to use it for a few seconds to clean something up
- can be used outside of the house where there is no power outlet - e.g. in the car in a rental apartment parking
Since I switched to cordless (which has been 6 years or so), I no longer dread vacuuming. It's actually a pleasant experience and sometimes, when I get a few minutes, I do a clean of areas that get dirty often (entrance).
The battery life and the power available have improved to the point where it's no longer something I worry about (especially for my two bedroom apartment).
I'll be the contrarian. I have a Roomba and a Dyson cordless. I'm very happy, and my home is much cleaner than with my old industrial-grade vacuum:
- The Roomba goes once a day. It doesn't pick up much in one pass, but my house is much cleaner because it runs all the time. Covering the same spot many times, it does well.
- The Dyson cleans very well, and picks up all the places the Roomba doesn't get to or emergency spills. It's never run out of batteries.
On the whole, it's less effort and cleaner than with my old big'un vacuum.
And if I want to do a deep clean, I'd rather wash in either case.
Funnily enough, the cord was the thing that eventually wore out due to normal use and needed to be replaced several times on all of our vacuums growing up. It's trivial to fix, but most don't know how and didn't want to lug a big heavy vacuum to a repair shop and just end up getting a new vacuum. I enjoy not tripping all over a cord or constantly having to tug it out of the way of where I want to vacuum. I enjoy not having to constantly plug/unplug it while moving from room to room when I run out of cord. I enjoy not having to wind the cord up after every use. It's so easy to clean the car and not have to weave the cord everywhere. I enjoy not having wear marks from the cord in the paint of the floor trim, which happens a lot in doorways as they protrude inward from the wall, or any time you go around a corner and pull the cord.
I switched from a Dyson corded vacuum to a Samsung battery powered one and it’s amazing. I’ll never go back to wired vacuums. My parents have a Dyson battery powered one and it is garbage.
Bought a house with a 30 year old Siematic kitchen... it all works, but maybe after 30 years you dont need it to work anymore. It's loud and not very energy efficient, and 30 years will leave some grime in places where toothbrushes don't go.
I have one of each and the cordless is the go-to for spot cleaning spills and vacuuming the stairs. My Miele canister vacuum is amazing, but a relative hassle.
Are they that bad? I’ve been interested in buying a cordless vacuum, and the Dyson ones seem to top all the review lists (e.g. Wirecutter). What are some good alternatives?
Not really relevant to cordless ones but I know Dyson removed their pre-motor filter on their latest corded vacuums. If the dust chamber is too full excess dust is blown through the motor and then stopped from coming out into the air by a post motor filter. This will lead to premature motor failure over time.
The Dyson 'bagless' idea is a bit of a sham. Yes they work, but they don't work that well. They don't make as much suction as their bagged competitors so they cheat and use smaller orifices to increase suction instead of by having a larger motor or alternative design. Then in order to have 'like new' performance all the time you have to continually wash (which doesn't really clean well enough) or replace filters.
Some people love them but they don't make sense to me. If I'm emptying my vacuum I'm going to empty it into a bag anyway so I may as well use a bagged vacuum that works more consistently and doesn't throw dust everywhere.
They are good in certain circumstances, but they use a few tricks, eg. there is no battery meter on the V6 to avoid range anxiety, so it will just die without warning and flash a LED vs having a battery gauge.
The suction is also pretty poor, however it makes up for it by having a roller in the vacuum head which picks up the dirt.
If you have anyone in the house with long hair its almost unusable as the roller will be clogged up after a single vacuum. A traditional vacuum with better suction and no roller wont have this issue.
On the plus side they are light and manoeuvrable, and the wall mount means you always keep it charged.
I have one of the cordless vacs. It works well at being a cordless, the size is great and it's easy to handle but...
It's made of really cheap plastic and has cracked in a few places.
Being bagless is good in that I can see what it's collected but bad in that when come to empty it the dust I'm allergic to goes everywhere. (If only someone would invent a bag to keep the dust in eh?).
I had a Dyson. I lost it in a breakup. I got a Shark. I figured any cordless stick vacuum is gonna get me what I want. The Shark is nowhere near as good. I found a Dyson on the street. It runs circles around the Shark. It's no contest. It makes it so easy to vacuum without all the ceremony of vacuuming from the past.
I guess people just like complaining, it works great, especially used together with a robotic vacuum cleaner for the easy locations. I just got some food on the floor an hour ago, I would have been lazy to get a wired vacuum cleaner there, but with Dyson wireless it was really easy.
I love their cordless vacuums. Mine's approaching 6 years with no issues whatsoever. My previous (corded) Dyson vacuum also works perfectly to this day, bought in 2006 and used at least every other day (because dogs) for 10 years. It fell down the stairs a couple of times, too. Really robust in my experience.
The cordless one does not quite match the suction, but it's so much more convenient and sufficient nonetheless.
I got a Black & Decker cordless vacuum and it works great. Great battery (~60-90m runtime on full charge) which is also easily swappable (same batteries as their drills) with decent suction, build quality feels good too. It's almost 3x cheaper than the Dyson so really great value
I have the Dyson V10. And I got it much cheaper by buying refurb and coupon stacking for <$200. I think they were the first to get the cordless vacuum formfactor right. There are many alternatives now that are significantly cheaper. And if I wasn't able to purchase mine at the price I did I probably would have considered them.
I have a V8, my wife loves it and I appreciate it as well. We have a large apartment, so we prefer cordless solutions. Dyson has a decent battery and enough of sucking force to be useful. Personally can recommend. It also cleans super easily, with one lever.
I have a corded dyson that doesn't use those dust bags, but it sucks (but not in the way a vacuum is supposed to). It's squeaky plastic and feels rough/wrong on the ground.
Don't know how good it is, but I'm considering a Bosch universalvac 18 since it uses the same batteries as a bunch of their cordless tools and garden products (18V) which I already have a couple of
I have a tineco cordless vacuum which I think is incredibly well built, I bought it because it topped the Consumer Reports leaderboard at the time I was looking for one
I tend to use paper towels too. Electric hand-dryers promote the build-up of bacteria given how microbial life prefers warm places and how often people will walk away before their hands are properly dry.
No idea about battery balancing in them though, maybe I need to open it and try to find out. My gut feeling is that they wouldn't save out on a few resistors.
Thank you for this. I'm shopping for a vac right now and this looks better than all the competition (Dyson, Samsung etc). What I wanted more than anything was a vacuum with easily available spares because vacs are one thing that tends to wear out and break more than any other appliance. I just hope Lupe does well and doesn't go out of business, otherwise there won't be any more spares.
It's not cost cutting. It's planned obsolencense! No Battery Engineer in their right mind would save a few cents on a balancing circuit. It's such a standard, it's like saving buying a car and the tank is sealed shut with gasoline inside.
Dyson is only a premium brand if you think so. Their products are, and have always been, garbage. It is a marketing company, not a premium household products company.
As another commenter here said, this is an obvious case of planned obsolescence.
I bought a Dyson V7, and the battery life even from new is atrocious. On a full charge, unable to cover my very modest London flat, and of course, it cannot be used while charging.
I even fitted a larger aftermarket battery. Still awkward to use. Eventually I gave up, and bought a corded Henry from Numatic.
I cannot recommend a cordless Dyson for anything except light dust busting.
Corded vacum for residential is such a thing of a past, can't believe genuine people fallback to cords over dysons... I use V8 and V11, wonderfull machines. I like V8 more because it light and nimble.
These little vacuums really suck! Seriously though, I didn't realize how impactful having a good vacuum would be. There are probably other-brand equivalents that cost less, but refurbished the Dyson handhelds aren't bad on price. The accessories are intuitive and "just work". I'm glad I didn't bawk at it when my fiancee wanted to buy it. And really cool to see more hardware mods getting attention on HN!
Readit News
Long story short, the fireware was indeed full of bugs. It is possible that these controller boards haven't been working right for the last 10+ years. I managed to add a few lines of code to bypass some initial values when the board is first powered up, and that fixed the issues. It is indeed an "on demand" defrost controller now. I'm still slowly writing a blog post about it but probably won't get more time to publish for a few months.
But I guess the point is, after messing with this, there seems to be an entire world of embedded firmwares that are just riddled with bugs and will never be fixed.
I’d love to see this blog post, if you end up having time to write it! Can you share a link to your blog? I didn’t see it in your profile.
Trane had the original patent for computer controlled defrost: https://patents.google.com/patent/US4573326A/en In the first image you'll see a chart with different temperature "bin" factors. In one place in the code, the temperature offset from 32 degrees (freezing) is added to a hardcoded value and the PC then jumps into a certain spot in a lookup table. The values in that lookup table help determine at what "DT" (delta temp between outdoor coil and outdoor ambient) a defrost should initiate. In another location, a hardcoded value is added to the PC along with a loop counter.... On loop 1 through the code, jump to this location, on loop 2 jump to this location, etc. Kind of a strange way to code, but after buying different revisions on ebay of this board going all the way back to the early 2000's, and on top of the patent being from 1985, perhaps this was the norm in the 80's and mid 90's.
I purchase my Dyson V7 as an official refurb and the battery went in to lockout a few months after the short refurb warranty expired. Thus prompting the project. The vacuum is pretty handy for my small apartment, and when I bought it, I wanted something that had decent reviews and was from a real company, not just some Amazon seller with a bunch of random characters for a name. I still like the vacuum, I just wish Dyson hadn't designed it to fail.
I think there are two issues here: 1) The left out the cell balancing circuitry which is pretty standard for battery packs. 2) They designed their firmware to go in to permanent lockout when the cells go to far out of balance (300mV).
For the sake of discussion, I've heard interesting two arguments on why they might have disabled cell balancing: 1) Cell balancing could be a weak point on the ISL94208 IC they used, so they could have disabled cell balancing to actually increase overall reliability. We'd never know for sure, but I could see this being plausible. This is from someone on the EEVblog thread (https://www.eevblog.com/forum/projects/fu-dyson-bms-an-(unof...)
2) Cell balancing isn't actually useful because a poor battery cell will plummet in voltage under load anyways due to the higher ESR in the poor cell. At least, that was my interpretation of their argument after translating it from Russian to English in a comment on the YouTube video. While I see their point, especially in the vacuum's turbo mode which draws 17A vs the usual 3A, I think there would still be some usable capacity to be gained by balancing the cells even if one did have a much higher ESR.
Also, this resembles why I'm very reluctant to buying an e-scooter in Sweden since basically all the ones available here are rebranded OEM Alibaba scooters with poor/fake battery implementations, so when it fails you'll be standing there with no way to get back on the saddle again.
Even the Swedish-branded Vessla scooters were rebranded OEMs from Alibaba, with minor cosmetic changes and a hefty premium. After a while the batteries turned out to be of poor quality, and after their v2, they quit that vertical entirely.
Looking forward to Segway launching their e-scooters in Sweden, at least I know it's a reputable brand standing behind it and can honor warranties etc. I want something quite small that I can have in the apartment (theft and vandalism otherwise), and can use to scoot my kid to school with.
https://hackaday.com/2022/05/23/fighting-back-against-dodgy-...https://news.ycombinator.com/item?id=31487401
Removing and replacing paper towels with hand dryers in public bathrooms has been an unfortunately shortsighted move that's been copied without much thought. Hands aren't the only thing that get wet in a public bathroom. You may wash your face, you may be removing stuff off your clothing, and countless other uses that a hand dryer alone can't accommodate.
The ultimate bachelor's vacuum cleaner was the Dyson DC15 Animal. It just cleaned and cleaned and cleaned, their newer stuff I dont rate.
Personally I'm never going back to a corded vacuum if I can avoid it.
The point of anything cordless is how it eliminates the hassle of, well, dealing with cords. In case of a vacuum cleaner, one has to:
- pull the cord out
- plug and re-plug it
- ensure it doesn't get stuck around the corners and under furniture legs
- ensure it doesn't pull some other furniture and topple them over
In addition, corded vacuums have practically no power envelope or weight restrictions, so they end up being bulky, heavy and loud, even if the context in which they are used doesn't require the power.
Dyson cordless (I can't speak to any other) in contrast:
- weighs lot less and can be carried around with ease
- can be moved around without a second thought of where the cord is or whether it can be maneuvered in a certain way
- is a lot quieter (can be used at night)
- is instantly accessible without any setup so it makes sense to use it for a few seconds to clean something up
- can be used outside of the house where there is no power outlet - e.g. in the car in a rental apartment parking
Since I switched to cordless (which has been 6 years or so), I no longer dread vacuuming. It's actually a pleasant experience and sometimes, when I get a few minutes, I do a clean of areas that get dirty often (entrance).
The battery life and the power available have improved to the point where it's no longer something I worry about (especially for my two bedroom apartment).
- The Roomba goes once a day. It doesn't pick up much in one pass, but my house is much cleaner because it runs all the time. Covering the same spot many times, it does well.
- The Dyson cleans very well, and picks up all the places the Roomba doesn't get to or emergency spills. It's never run out of batteries.
On the whole, it's less effort and cleaner than with my old big'un vacuum.
And if I want to do a deep clean, I'd rather wash in either case.
Our next kitchen won't be a Siematic.
The Dyson 'bagless' idea is a bit of a sham. Yes they work, but they don't work that well. They don't make as much suction as their bagged competitors so they cheat and use smaller orifices to increase suction instead of by having a larger motor or alternative design. Then in order to have 'like new' performance all the time you have to continually wash (which doesn't really clean well enough) or replace filters.
Some people love them but they don't make sense to me. If I'm emptying my vacuum I'm going to empty it into a bag anyway so I may as well use a bagged vacuum that works more consistently and doesn't throw dust everywhere.
The suction is also pretty poor, however it makes up for it by having a roller in the vacuum head which picks up the dirt.
If you have anyone in the house with long hair its almost unusable as the roller will be clogged up after a single vacuum. A traditional vacuum with better suction and no roller wont have this issue.
On the plus side they are light and manoeuvrable, and the wall mount means you always keep it charged.
It's made of really cheap plastic and has cracked in a few places.
Being bagless is good in that I can see what it's collected but bad in that when come to empty it the dust I'm allergic to goes everywhere. (If only someone would invent a bag to keep the dust in eh?).
The cordless one does not quite match the suction, but it's so much more convenient and sufficient nonetheless.
Dyson aren't awful but they're definitely overpriced.
Deleted Comment
I've been using Dyson products since 2005. Happy to shine some light on why people pay for it voluntarily :)
Vacuum wars were impressed at least https://youtu.be/rFbkGM9Lm18
No idea about battery balancing in them though, maybe I need to open it and try to find out. My gut feeling is that they wouldn't save out on a few resistors.
I knew that cost cutting in consumer electronics was bad, but I didn't know it was THAT bad, especially for a premium brand like Dyson.
And that's coming from someone within the industry.
Not assuming that is the reason, but it certainly seems like a "positive" side effect for manufacturers.
As another commenter here said, this is an obvious case of planned obsolescence.
I even fitted a larger aftermarket battery. Still awkward to use. Eventually I gave up, and bought a corded Henry from Numatic.
I cannot recommend a cordless Dyson for anything except light dust busting.