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I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

james.belchamber.com

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Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#141

Post by bluesign »

devinvs wrote: post #139
bluesign wrote: post #129

Earlier quoted context omitted.

I think this is the format, some parts are split ( maybe some obfuscation attempt ) 0-4 month 4-7 year 8-10 hour 11-15 day 22-23 hour 24-29 flags 30-31 year

I might be misunderstanding, but this seems very wrong. your method on the first entry: 10011011010100101100001101010000 year = 101 00 (20? year should be 25 or 2025) month = 1001 (9, but month is Nov) day = 1001 (9, not enough bits to encode large days) hour = 01 1 or 01 11 (3, 7, or 14 reversed, should be 11) no minute field

ah sorry, when I was debugging I changed the endianness.

  0x9B530150 -> 0x5001539B ->
  01(year_1) 010000(flags) 00(hour_2) 000001(minute) 01010(day) 011(hour_1) 1001(year_2) 1011(month)
  month 1011 -> 11
  year  01 1001 -> 25
  day = 01010 -> 10
  hour = 011 00 -> 12
  minute = 000001 -> 1


 with no endianness change should be: 

 1001(year_2) 1011(month) 01010(day) 01100(hour) 000001(minute) 01(year_1) 010000(flags)

 with your data:

 1001(year_2) 1011(month) 01010(day) 01011 (hour) 000011(minute) 01(year_1) 010000(flags)
 
 16+9=25       11            10        11              3

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#142

Post by ninju »

noisy_boy wrote: post #111
SecretDreams wrote: post #100

Earlier quoted context omitted.

I think we need a data point where you are driving and talking to your wife. For science.

Drill down further - driving vs idling on traffic stops.

And drilling down on the other dimension...talking vs. listening to wife

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#143

Post by cyanydeez »

adirelle wrote: post #126
rhyperior wrote: post #110

Earlier quoted context omitted.

A PA explained to me once: they’re taught you have to sneak quietly into a room where the patient has been sitting in the dark listening to soothing music for 15 minutes and take their BP measurement without them noticing. Goals.

You are kidding but having hypertension issues for years, I can confirm you that tension is a highly-dynamic value that can change in few minutes for a lot of reasons. Here the standard toi

There's more evidence that taking with lying down is better.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#144

Post by cyanydeez »

alexfoo wrote: post #17
cestith wrote: post #2

Regarding white coat hypertension, the shot isn’t always necessary. Some people’s blood pressure just goes up from the stress of the clinical setting.

White coast hypertension isn't just about a clinical setting, it's more generally about the worry about the results of having your BP measured. [EDIT] OK, well maybe there's another type of hypertension which is related to anxiety about a high result regardless of the measurement setting. I have to take daily BP measurements during titration for ADHD medication. (Using an _A&D UA-611 Plus_ machine at home.) I can put…

Check out the ASUS vivo watch. It can measure using a transit pulse index. At least gives you some finer grained data.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#145

Post by cyanydeez »

hermitcrab wrote: post #113

I am having issues with hypertension and purchased one of these: https://hilo.com You put on a cuff (supplied) to calibrate it, and then you wear a little gadget on your wrist. It takes frequent measurements throughout the day and night when it senses you aren't moving. It then syncs with your phone to store the results. Its a little pricey, but seems to work well[1]. And it avoids the faff of a pressure cuff[2] and…

Checkout the ASUS Vivo watch. Less technical but gives fine grained measurements.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#146

Post by cyanydeez »

pinkmuffinere wrote: post #19

> I tried feeding a lot of this into various Als (Kagi gives you access to a few with a nice interface) and I found that they mostly were stupid in ways that made me think "stupid in ways that made me think" is (IMO) a really good summary of how AI is useful, as well as its pitfalls.

Unfortunately, we already know a large percentage of the population doesn't want to think.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#147

Post by cyanydeez »

ndsipa_pomu wrote: post #135

I enjoyed the writing style (maybe it's the mistrust of Windows). I'm currently wearing a cheap smart-watch (<£20) that I spotted on AliExpress (i.e. Chinese product) that unbelievably records biometrics such as blood pressure and blood lipid profiles. I was mainly curious about the uric acid measurements as I get the occasional attack of gout, but am curious as to whether it actually does measure anything like blood…

I've got an ASUS Vivo watch and it measures a transit pulse index and that's supposed to correlate with blood pressure. It needs to be recalibrated frequently and seems good enough.

But when you look at everyone's experience with blood pressure, it actually seems like it's BP that's just not reliable and a better type of measurement would be helpful.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#148

Post by hermitcrab »

barbazoo wrote: post #140
victor106 wrote: post #118

Earlier quoted context omitted.

how accurate is this?

> The Hilo Band uses photoplethysmography (PPG)—an optical sensor technology that collects data from your wrist. This data is sent securely through the Hilo App to Hilo’s cloud server, where advanced algorithms estimate your blood pressure using Pulse Wave Analysis (PWA), which looks beyond just the rate of your pulse, and examines the unique form of each heartbeat’s pressure through your blood vessels. I doubt that…

I can do 3 cuff readings within 5 minutes are easily get +- 10 for each measurement. So it doesn't have to be super precise to have comparable accuracy to a cuff. Also the fact it is making continuous readings (even while asleep) is very helpful.

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#149

Post by cosmojg »

hermitcrab wrote: post #120
victor106 wrote: post #118

Earlier quoted context omitted.

how accurate is this?

It seems pretty consistent with a cuff. Also it doesn't jump around wildly from one minute to the next.

How comfortable is it? Do you have to wear it particularly tightly around your wrist or can you let it hang a little loose like a watch?

Re: I didn't reverse-engineer the protocol for my blood pressure monitor in 24 hours

#150

Post by zimpenfish »

lifeisstillgood wrote: post #138
zimpenfish wrote: post #82

Earlier quoted context omitted.

> "It will not connect to Apple Health" FWIW the latest version of the app does export the previous day's averages to Apple Health (only when you open the app, mind, which can make it look like there's missing data.) I use BPExtract to read the PDF and export every reading to Apple Health but I'll definitely be giving your stuff a go as well (because automation >> manual every time.)

So this when they became a new brand (?) called Hilo. I am not following their business but presume something is up. Of course the format change seems to have broken the extractor so the next free lunchtime(s) I get will fix it. I assumed no one else uses it so was not in a hurry - any feedback gratefully recvd :-)

> So this when they became a new brand (?) called Hilo.

Around the same kind of time, yeah - when the app got a (not great) refresh.

> I am not following their business but presume something is up.

I think someone just realised that "Aktiia" is a godawful name and "Hilo" (with the new actually good logo) is much better.

> I assumed no one else uses it so was not in a hurry - any feedback gratefully recvd :-)

Will give it a run out tomorrow. Didn't even knew it existed which is to my shame.

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