Micro SD Data Logging

Comments

• SRLM Posts: 5,045

  2014-05-07 19:04 edited 2014-05-07 19:04

  You should use [ code ] tags to post your code. What you've posted does not include indentation, so it's impossible to tell what the control flow is.
  
  In any case, you'll probably want to add some commas ( sdfat.pputc(',') ) and newlines ( sdfat.pputc('\n') ) to make your code output CSV.
• JLocke Posts: 354

  2014-05-08 06:24 edited 2014-05-08 06:24

  Here's some code I used in a data logging project that writes temperature/humidity to a micro-SD card:

  {
  ===============================================================================
  }
  VAR
    byte NewLocTemp                 ' flag to indicate local temp changed
    byte NewDwnTemp                 ' flag to indicate downstairs temp changed
    byte NewOutTemp                 ' flag to indicate outside temp changed
    byte SettingRTC                 ' flag to indicate we're setting the date/time
    byte LockLCD                    ' flag to lock access to LCD
    byte Dow                        ' day of the week
    byte RcvChar                    ' Xbee received character
    byte XbData[BUFFSIZE]           ' Xbee receive buffer
    byte DownTemp[STRINGSIZE]       ' downstairs temperature
    byte OutTemp[STRINGSIZE]        ' outside temperature
    byte OutHumid[STRINGSIZE]       ' outside humidity
    byte FilName[FNAMESIZE]         ' filename buffer for SD
    byte FilData[DATASIZE]          ' line buffer for write to SD
    long DateTime                   ' current date/time in Unix format
    long LocTemp                    ' local temperature (F) from SHT11 (float)
    long LocHumid                   ' local humidity (% rh) from SHT11 (float)
            
    long stackTemps[130]            ' stack for temperature cog
    long stackRemote[170]           ' stack for communications cog
    long stackButton[30]            ' stack for button monitoring cog
    long stackLog[250]              ' stack for data logging cog
  
  {
  ===============================================================================
  }
  OBJ
    Comms    : "FullDuplexSerial4port"        ' for comm ports
    Rtc      : "DS1307_RTCEngine"             ' real time clock chip
    Sht      : "Sensirion_full"               ' SHT11 temperature/humidity chip
    Drv      : "fsrw"                         ' file system driver
    SimplNum : "Simple_Numbers"
    Flt      : "FloatMath"                    ' floating point support
    FltStr   : "FloatString"
    Tyme     : "jl_unix_time"                 ' date/time conversion
  
  {
  ===============================================================================
  }
  
  PUB cog_Log | crntDay, minit, locTime, yyyymmdd, hhmmss
    ''* writes current data to µSD on schedule (every 15 minutes)
    ''
    ' == cog initialization ==
    waitcnt((clkfreq * 2) + cnt)                   ' wait for date/time to be valid
    ByteFill(@FilName, 0, FNAMESIZE)               ' clear the filename buffer
    locTime := DateTime                            ' copy the global DateTime variable
    yyyymmdd := Tyme.date(locTime, 0)              ' decode it
    hhmmss   := Tyme.time(locTime, 0)
    
    Concatenate(@FilName, SimplNum.decx(yyyymmdd.word[1], 2)) ' build the filename
    Concatenate(@FilName, string("-"))
    Concatenate(@FilName, SimplNum.decx(yyyymmdd.byte[1], 2))  
    Concatenate(@FilName, string("-"))
    Concatenate(@FilName, SimplNum.decx(yyyymmdd.byte[0], 2))
    Concatenate(@FilName, string(".csv"))          ' save as '.csv' file
    Drv.mount(0)                                   ' mount the disk
    Drv.popen(@FilName, "a")                       ' open the file
    Drv.sdstr(string("=== REBOOT ===", 13))        ' add indicator line
    Drv.sdstr(@FileHeader)                         ' add header line
    Drv.sdstr(string(" ", 13))                     ' blank line
    Drv.pclose                                     ' flush and close the file  
  
    crntDay := yyyymmdd.byte[0]                    ' init the triggers
    minit   := hhmmss.byte[1]
  
    ' == cog loop ==
    repeat
      locTime := DateTime                        ' copy the global DateTime variable
      yyyymmdd := Tyme.date(locTime, 0)          ' decode it
      hhmmss   := Tyme.time(locTime, 0)
      
      if crntDay <> yyyymmdd.byte[0]             ' day changed?
        crntDay := yyyymmdd.byte[0]              ' copy the new value
        ByteFill(@FilName, 0, FNAMESIZE)         ' clear the filename buffer
  
        Concatenate(@FilName, SimplNum.decx(yyyymmdd.word[1], 2)) ' build the filename
        Concatenate(@FilName, string("-"))
        Concatenate(@FilName, SimplNum.decx(yyyymmdd.byte[1], 2))  
        Concatenate(@FilName, string("-"))
        Concatenate(@FilName, SimplNum.decx(yyyymmdd.byte[0], 2))
        Concatenate(@FilName, string(".csv"))    ' save as '.csv' file
  
        Drv.mount(0)                             ' mount the disk
        Drv.popen(@FilName, "a")                 ' open the file
        Drv.sdstr(string(" ", 13))               ' blank line
        Drv.sdstr(@FileHeader)                   ' add header line
        Drv.sdstr(string(" ", 13))               ' blank line
        Drv.pclose                               ' flush and close the file
  
      if minit <> hhmmss.byte[1]                 ' minute changed?
        minit := hhmmss.byte[1]                  ' copy the new value
  
        ifnot (minit // 15)                      ' every 15 minutes
          Drv.mount(0)                           ' mount the disk
          buildDataString                        ' assemble the log line
          Drv.popen(@FilName, "a")               ' open the file
          Drv.sdstr(@FilData)                    ' write data
          Drv.pclose                             ' flush and close the file
  
      waitcnt(clkfreq + cnt)                     ' wait 1 second
  
  {
  ===============================================================================
  }
  PUB buildDataString | locTime
    ''* builds the line to write to the µSD disk
    ''
    locTime := DateTime                            ' copy the global DateTime variable
    ByteFill(@FilData, 0, DATASIZE)                ' clear the buffer
    Concatenate(@FilData, Tyme.jl_date_str(locTime, 0))
    Concatenate(@FilData, string(","))
    Concatenate(@FilData, Tyme.jl_time24_str(locTime, 0))
    Concatenate(@FilData, string(","))
  
    Concatenate(@FilData, FltStr.FloatToFormat(LocTemp, 5, 1)) ' upstairs temp
    Concatenate(@FilData, string(","))
    Concatenate(@FilData, FltStr.FloatToFormat(LocHumid, 5, 1)) ' upstairs humidity
    Concatenate(@FilData, string(","))
    Concatenate(@FilData, @DownTemp)               ' downstairs temp
    Concatenate(@FilData, string(","))
    Concatenate(@FilData, @OutTemp)                ' outside temp
    Concatenate(@FilData, string(","))            
    Concatenate(@FilData, @OutHumid)               ' outside humidity
    Concatenate(@FilData, string(13))    
  
  {
  ===============================================================================
  }
  PUB Concatenate(whereToPut, whereToGet)
    '' Concatenates a string onto the end of another. This method can corrupt memory.
    '' Returns a pointer to the new string.
    ''  whereToPut - address of the string to concatenate a string to.
    ''  whereToGet - address of where to get the string to concatenate.
    ''
    bytemove((whereToPut + strsize(whereToPut)), whereToGet, (strsize(whereToGet) + 1))
    return whereToPut
  
  {
  ===============================================================================
  }
  DAT
    FileHeader  byte "Date,Time,Upstairs (F),Humidity (%),Downstairs (F),Outside (F),Humidity (%)", 13, 0
  
  

  
  One difference I notice is that in my code I always open the file with 'a'; not sure if that makes a difference here. Anyway, I hope this helps you out.
• Lev Posts: 182

  2014-05-08 15:54 edited 2014-05-08 15:54

  The code I sent you a while ago works fine in high altitude ballooning. I have used it in 4 flights now and accumulated thousands of lines of data in a csv file. I haven't experienced any of the problems you describe so I suspect that there is something different in the way you implemented the code snippets I sent.
  
  I notice that you do not have a pause in the repeat loop (or, maybe you didn't send all of the code below the repeat). You might try slowing the loop down a bit. That would give some extra time for the card to mount/unmount. In mine, I wrote to the SD card every 10 seconds.
• aparis1983 Posts: 22

  2014-05-22 20:16 edited 2014-05-22 20:16

  You were right!! I inserted a waitcnt(clkfreq * 5 + cnt), and I also added an sdfat.popen( string("Data.csv"),"a") to the loop so the file is continuously appended. Works perfect and is logging values every 5 seconds.
  
  Now the only thing I'm worried about is the several corrections needed for lower operational temperatures. I've read about this in the forum but not sure where to begin to include these corrections. At any rate, I have no time to work on it as the balloon is launching on Saturday. Hoping for the best.
  
  Thanks!
• Lev Posts: 182

  2014-06-14 06:39 edited 2014-06-14 06:39

  aparis1983 wrote: »

  You were right!! I inserted a waitcnt(clkfreq * 5 + cnt), and I also added an sdfat.popen( string("Data.csv"),"a") to the loop so the file is continuously appended. Works perfect and is logging values every 5 seconds.
  
  Now the only thing I'm worried about is the several corrections needed for lower operational temperatures. I've read about this in the forum but not sure where to begin to include these corrections. At any rate, I have no time to work on it as the balloon is launching on Saturday. Hoping for the best.
  
  Thanks!

  
  That is great news! Let us know how the flight goes.