S9 data files and format, Part II, Datalog directory

There are four types of files in the datalog directory. Some were pretty well identified in a discussion last spring, but here's more info. The file names are in the format of Date+time+XXX.edf, where XXX is BRP, SAD, PLD, or EVE. All of them are written to the card as soon as you turn the S9 off, i.e., stop the air flow. If you turn the machine off two or more times during the night, say to go to the bathroom, you will then have that many sets of files for that day on the card. None are stored in machine memory after being written to the card.

The BRP data file is the high resolution Flow and Mask pressure data you see in Resscan. The clinician's manual says flow is recorded 25 times per second and mask pressure twice per second. However, the BRP file has both data recorded 25 X per second. The BRP file is recorded for only seven days. Each day the oldest day's files are overwritten by the current day's files. When I loaded the text file for only one day into Lotus 1-2-3 it filled up the limit on rows, 65,536, on each of 5 tabs and almost 40,000 on the sixth tab! There's no way to manually crunch all that data in a reasonable period of time!

The PLD data file is the most inclusive data file. Here's the data field names for the PLD file.
Mask Pres, Therapy Pres, Exp Press, Leak, RR, Vt, MV, Snore Index, FFL Index
Data in the PLD file is recorded once per second and the file is kept on the card for a max of 30 days. S9 machine parameters such as max & min pressure are stored in the summary data STR file in the root directory.

The SAD file stores oxygen monitoring data if you are using an O2 monitor. It has O2 level and breaths per minute. The SAD file is kept for 30 days on the card.

The EVE file contains info about the events shown on the events graph. When extracted the info is in a text file labeled date+time+EVE_annotations.txt. It gives the time of onset of the event, it's duration, and the type.

Again, I hope this is useful to someone. It's been kind of fun sorting through it all. Any questions just ask.

Resscan does a super job of sorting through all the data files and combining them into the graphs we see in it. Sure beats trying to interpret that stuff from spreadsheets!