Saturday, October 12, 2019

CMS 50D+ pulse oximeter

I purchased a CMS 50D+ pulse oximeter from Amazon for $38 in 2015.

How a pulse oximeter works: https://www.howequipmentworks.com/pulse_oximeter/

USB

The first time I plugged the device into my USB port, dmesg reported the following:

[  113.192067] usb 4-1: new full speed USB device number 2 using uhci_hcd
[  113.581236] usbcore: registered new interface driver usbserial
[  113.581253] USB Serial support registered for generic
[  113.581288] usbcore: registered new interface driver usbserial_generic
[  113.581290] usbserial: USB Serial Driver core
[  113.590473] USB Serial support registered for cp210x
[  113.590511] cp210x 4-1:1.0: cp210x converter detected
[  113.700056] usb 4-1: reset full speed USB device number 2 using uhci_hcd
[  113.843245] usb 4-1: cp210x converter now attached to ttyUSB0
[  113.843265] usbcore: registered new interface driver cp210x
[  113.843267] cp210x: v0.09:Silicon Labs CP210x RS232 serial adaptor driver


I'm not sure how to poll the saved data, or get live data from the USB device

See this analysis
https://www.tranzoa.net/~alex/blog/?p=371
and
http://www.jimmynewland.com/wp/about-jimmy/presentations/comparing-ppg-signals-open-vs-closed/
with source code
https://github.com/jimmynewland/paths-up-expeditions-in-computing-ret2018
specifically
https://github.com/jimmynewland/paths-up-expeditions-in-computing-ret2018/blob/master/cms50dplus.py

Ubuntu 

In Ubuntu, I installed SleepyHead
http://sleepyhead.sourceforge.net/wiki/index.php?title=Main_Page
http://jedimark64.blogspot.com/p/sleepyhead.html
http://sourceforge.net/projects/sleepyhead/
http://sourceforge.net/projects/sleepyhead/files/Releases/Linux/

sudo dpkg -i sleepyhead_0.9.2-1_i386.deb
SleepyHead
I can view live data and save data to file.

cd ~/Documents/SleepyHeadData/Profiles/
go into the most recent directory, ie
cd CMS50_560ee6c6

Although I am able to see the save files, they are binary and I cannot read them.
SleepyHead hits a segfault

Windows XP

The pulse oximeter came with a mini-CD with application software for Windows. I installed the SPO2 Assistant exe, which included a CP210x USB to UART Bridge Driver Installer.

Two programs are installed: "SPO2 Review v1.5" and "SPO2 manager v1.5"

"SPO2 manager v1.5" automatically saves the live data to "C:\program files\Sp02\Data" in both binary and CSV format! Yay


1 comment:

  1. Latest software is available from https://www.sleepfiles.com/OSCAR/ and https://gitlab.com/pholy/OSCAR-code

    ReplyDelete