Page 3 of 8

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 5:42 am
by upforsleep
I had the same problem. I ordered an new data cable and that fixed the issue for me.

http://www.pulseoximeter.org/usb-cable. ... medium=ppc

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 5:48 am
by Madalot
49er wrote:
TASmart wrote:I found my best way to contact Amazon is to use the online chat. They are fast and extremely eager to please. I have even had them refund my money for an ordered item that was late on delivery, and let me keep the item. They are very good to work with.
Sorry for this OT response but it was through online chat that a Cricket rep fixed my cell phone voice mail problem. The telephone rep was clueless.

I always call Amazon when I have a problem but your post is an excellent reminder that online chats can be very helpful.
I always used chat with Amazon and have had excellent results. In fact, I tend to choose "chat" with any company that offers it because it does away with the possible accents that I can't understand. Plus with chat, I can keep doing other things and not have to focus on a telephone call.

As with your experience with Cricket, I find that using chat almost always gets good results.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 7:05 am
by archangle
xxyzx wrote:besides their cable is IDENTICAL to any USB cable. there is nothing different about it.

do you know how cheap standard cables are
do you know how expensive a custom cable woudl be
they cut every possible corner to make this device cheap not good
the problem is not the cable, but yes i did use their cable.
it is software issues and terrible documentation making that harder.
The cable has USB plugs on both ends, but one end has a chip molded into the plastic. It converts USB into some other protocol. I think it's a RS-232 or a variant. Quite a few devices use such "custom" cables.
xxyzx wrote:do you know how expensive a custom cable woudl be
Yes I do. They're really cheap in quantity. They made a custom mold for the case of the oximeter, and a custom display. A custom cable isn't a big deal compared to the other custom parts for this oximeter.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 8:28 am
by LibtardsUnite!
xxyzx wrote:
chunkyfrog wrote:I wonder if he tried to connect with a cable other than the proprietary cord that is shipped with the pulse-ox.
It looks exactly like a generic cord, but surprise! Proprietary--humor at a discount.

I used their cable. it is software bugs and incompatibilities with various versions of windoze.

besides their cable is IDENTICAL to any USB cable. there is nothing different about it.

do you know how cheap standard cables are
do you know how expensive a custom cable woudl be
they cut every possible corner to make this device cheap not good
the problem is not the cable, but yes i did use their cable.
it is software issues and terrible documentation making that harder.

It's bad enough he's a moron, but then he confirms it by making STUPID and INACCURATE statements like this!

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 10:06 am
by Guest
he is a PC-noob ... he doesn't even know where the SHIFT-Key is or what it does.
He is that delusional that he thinks he is typing by using a "text to speech" 'app'. (Let that one sink in^^)

I have seen IRC-Chat-Bots who look more 'human' than him (or that).

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 11:03 am
by chunkyfrog
Maybe someone at Amazon is psychic--and tasked by mysterious powers of the universe to mete out karma.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 11:12 am
by Marillion
I've always been a firm believer in karma, or whatever you would like to call it.

My experience with Amazon returns has always been stellar, mirroring much of the positive comments already provided by others here.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 11:48 am
by 49er
chunkyfrog wrote:Maybe someone at Amazon is psychic--and tasked by mysterious powers of the universe to mete out karma.
Thanks for a good laugh CF.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 12:00 pm
by Gryphon
On a side note - Can't always assume because it looks like a duck and quacks like a duck that it isn't something else... At least when it comes to cables. You can usually at least "TRY" a standard cable with out causing damage unless you see instructions indicating otherwise.

It's very simple to change the wiring of one or more pins in a usb cable to make it proprietary. "You know how expensive it is to make a costume cable?" No wear near as much money as you can get back when your customer breaks said cable and instead of getting a replacement for a few dollars has to come back to you and spend like 5 times that for your "Special cable" ultimately the customization of a cable to make it proprietary is usually not a big issue. "it's just not usually done with out good reason because people find it a very questionable business practice." I know people will swear off of buying a company's products if they're constantly having issues with proprietary accessories and peripherals at least with the computer industry. It was that way for me in the past. Most things now days are standard.

Example - 20+ years ago "Compac" made smaller CD drives for their desktop computers and charged over 150 dollars for the drive when a 30 dollar drive would work fine. Solution? Take a hack saw to the case and make the drive bay about a 1/4th of an inch taller and install the 30 dollar drive - Problem solved. But you see my point.

I find it very nasty if a company creates proprietary devices for the sake of exclusivity. "It's one of my pet peeves with Apple in some cases" You make a change to your device for no other reason then to make everyone go out and pay a premium for your special adapter or cable that only works with your device. "Long time ago" Apple phones changed the port on their headphone jacks... very very simple change that caused a lot of headphones that were on the market to not fit. Apple made a lot of money in the short term selling more headphones for their devices until the market corrected and now almost all headphones are sold with a narrower connection at the base were they plug in.

If there is a design issue for it I have no objection. But as I said if they're doing it just to make money by monopolizing on accessories I think it's a very petty way of making extra money.

PS: I also have had no issues with Amazon. Both me and my wife have ordered hundreds of things through them and they always try to make things right when there is a problem. I've had them refund money when there was a problem or resend me product when mine was stolen and never arrived in the mail. I would try a bit harder before I started disparaging amazon for their bad service. When most of the people respond that they've had no problems what so ever. Your ether very unlucky or your doing something wrong.

Good luck to you though.

Gryphon

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 2:48 pm
by palerider
xxyzx wrote:the cable is marked with the usb standard symbol

if they changed anything they will get sued by the usb consortium
It's marked with the USB symbol, because it plugs into USB, you colossal moron.
xxyzx wrote:i have to think that the conversion chip is in the device and it uses the standard usb cable they provided
the problem is the bizarre software
As usual, your "thinking" and reality are far removed from each other.

Did you ever wonder why, when you plug in the cable by itself, that your computer recognizes that something was plugged in? I'm sure you didn't.

That wouldn't happen with a plain USB cable.

Plugging in the bare cable, by itself, no oximeter, into my linux system:

Code: Select all

Oct 10 15:45:24 tyr kernel: [601567.629957] usb 3-2: new full-speed USB device number 9 using xhci_hcd
Oct 10 15:45:25 tyr kernel: [601567.791131] usb 3-2: New USB device found, idVendor=10c4, idProduct=ea60
Oct 10 15:45:25 tyr kernel: [601567.791138] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Oct 10 15:45:25 tyr kernel: [601567.791142] usb 3-2: Product: CP2102 USB to UART Bridge Controller
Oct 10 15:45:25 tyr kernel: [601567.791145] usb 3-2: Manufacturer: Silicon Labs
Oct 10 15:45:25 tyr kernel: [601567.791148] usb 3-2: SerialNumber: 0001
Oct 10 15:45:25 tyr mtp-probe: checking bus 3, device 9: "/sys/devices/pci0000:00/0000:00:1c.6/0000:0e:00.0/usb3/3-2"
Oct 10 15:45:25 tyr mtp-probe: bus: 3, device: 9 was not an MTP device
Oct 10 15:45:25 tyr kernel: [601568.375482] usbcore: registered new interface driver usbserial
Oct 10 15:45:25 tyr kernel: [601568.375496] usbcore: registered new interface driver usbserial_generic
Oct 10 15:45:25 tyr kernel: [601568.375508] usbserial: USB Serial support registered for generic
Oct 10 15:45:25 tyr kernel: [601568.378353] usbcore: registered new interface driver cp210x
Oct 10 15:45:25 tyr kernel: [601568.378369] usbserial: USB Serial support registered for cp210x
Oct 10 15:45:25 tyr kernel: [601568.378401] cp210x 3-2:1.0: cp210x converter detected
Oct 10 15:45:25 tyr kernel: [601568.392048] usb 3-2: cp210x converter now attached to ttyUSB0
A plain cable wouldn't do that.

I'm sure there's some indication on a windows machine that a new device has been plugged in.

People more intelligent than you can see this for themselves.

There's some true facts for everybody.

ftdi: http://www.readytoflyquads.com/cp2102-u ... d=noscript note the part number, vs the log above.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 2:51 pm
by TASmart
Dude, "colossal moron" nearly made me spit coffee on my keyboard.

Re: warning - do not buy cms 50d+ from amazon

Posted: Tue Oct 10, 2017 10:34 pm
by Rumbert
palerider wrote:Oct 10 15:45:25 tyr kernel: [601567.791142] usb 3-2: Product: CP2102 USB to UART Bridge Controller
I probably don't know as much about this as Palerider but I'm a programmer who has written software for serial devices which helps me understand what's going on here. I want to confirm what Palerider said. This line of text from Palerider's computer proves that the cable is not a plain USB cable. The cable contains a chip called a CP2102 which translates between the oximeter and the computer. The oximeter speaks serial language and the computer speaks USB language and the chip translates so they can understand each other.

Earlier in this thread, somebody assumed that if the cable isn't plain USB then it must be an expensive custom cable. This is the kind of assumption that people jump to when their knowledge is limited. One of the things that happens when people gain experience in an area is that they make fewer assumptions. It takes time to gain experience. You can't gain it instantly by reading something. People who think they are experts because they've read a few things, are often deluding themselves. It's a kind of foolishness. It takes years of experience to become an expert.

The assumption is wrong because although this cable isn't plain USB, it's not an expensive custom item either. There was a third possibility which didn't occur to the person who jumped to the conclusion. This cable is a fairly standard commodity. For example, here's an offering page from a Chinese supplier offering a similar (not necessarily identical, but similar) cable in quantity:

Offering page for similar cable

Why is this type of cable fairly standard? Because many manufacturers, not just Contec, build devices that use serial communications but which need to plug into USB ports on computers. If the device is small like the CMS 50d+ it's not possible to put an ordinary serial socket on it, because a serial socket is too big, so they use a mini-USB socket instead. And so the engineers at the company end up with a need for the same cable we're discussing here.

We can see that this type of cable is manufactured cheaply by looking at prices for it when it ends up in retail outlets for the final buyer. For example:

Similar cable offered in retail for $9.99

I've never seen this type of cable in real life but from the photos it looks to me like the "lumps" at the computer ends of these cables are bigger than the lumps on plain USB cables. That would make sense because there's a CP2102 inside. In which case anybody can distinguish these cables from plain ones at a glance.

If anybody wants to dive deeper into how the CMS 50D+ communicates over this cable, here's a blog post by an engineer who reverse engineered the protocol:

CMS 50D+ serial protocol

Edit: Oops, my mistake, that last link is for the CMS50E not the CMS 50D+. I don't know if they use the same protocol.

Re: warning - do not buy cms 50d+ from amazon

Posted: Wed Oct 11, 2017 12:08 am
by palerider
Rumbert wrote: If anybody wants to dive deeper into how the CMS 50D+ communicates over this cable, here's a blog post by an engineer who reverse engineered the protocol:

CMS 50D+ serial protocol

Edit: Oops, my mistake, that last link is for the CMS50E not the CMS 50D+. I don't know if they use the same protocol.
Just FYI, they do.

PS, thank you for the "true facts". :cough:

Re: warning - do not buy cms 50d+ from amazon

Posted: Wed Oct 11, 2017 5:27 am
by Rumbert
palerider wrote:PS, thank you for the "true facts". :cough:
Thank you for reading all the way to the end.

Re: warning - do not buy cms 50d+ from amazon

Posted: Wed Oct 11, 2017 8:56 am
by DyslecticLibtardsUNTIE!
Guest wrote:he is a PC-noob ... he doesn't even know where the SHIFT-Key is or what it does.
He is that delusional that he thinks he is typing by using a "text to speech" 'app'. (Let that one sink in^^)

I have seen IRC-Chat-Bots who look more 'human' than him (or that).

Some of the problem could be he is running Windows XP. The drivers may not work on that old windows computer he dug out of a dumpster.