Issues with V2 firmware and lead off detection

Comments

• wjcroft Mount Shasta, CA

  November 2016

  Mentioning the V2 firmware developer, AJ Keller @pushtheworld .

  
  
• pushtheworld

  November 2016 edited November 2016

  @sardet sounds Are you trying to write firmware code to automatically check the impedances? 

  
  

  Do you have any links to the firmware you are trying to write so I can check it out? I'm sure we can figure this out.

  
  

  The main function that runs impedance checking is https://github.com/OpenBCI/OpenBCI_32bit_Library/blob/master/OpenBCI_32bit_Library.cpp#L668 where each character comes in one at a time.

  
  

  If you want to directly fire impedance checking from the `.ino` file I would suggest using this function:

  https://github.com/OpenBCI/OpenBCI_32bit_Library/blob/master/OpenBCI_32bit_Library.cpp#L1180 
• sardet

  November 2016

  Thanks for feedback.
  
  @pushtheworld yes, that's what I was trying to do.

  
  

  I tried to use your suggestion, using the 'streamSafeLeadOffSetForChannel' method on the '.ino' file, but I was not successful.

  For instance, if I wanted to automatically check the impedance on channel 1, I think I could change the 'setup' function as:

  
  

  void setup() {
  // Bring up the OpenBCI Board
  board.begin();
  
  // Notify the board we want to use accel data
  board.useAccel = true;

  
  

  //Impedance

  board.streamSafeLeadOffSetForChannel(0x00, OFF, ON); 

  }
  

  
  

  I also tried the following way without good results.

  
  

  void setup() {
  // Bring up the OpenBCI Board
  board.begin();
  
  // Notify the board we want to use accel data
  board.useAccel = true;

  
  

  byte N_setting = board.RREG(LOFF_SENSN,BOARD_ADS);

  board.leadOffSettings[0][NCHAN] = ON;

  bitSet(N_setting, 0);

  board.WREG(LOFF_SENSN,N_setting,BOARD_ADS);

  
  

  }

  
  

  Could you tell me what I am doing wrong?

  
  

  thanks!
• pushtheworld

  November 2016 edited November 2016

  @sardet, reading the comment above the function (https://github.com/OpenBCI/OpenBCI_32bit_Library/blob/master/OpenBCI_32bit_Library.cpp#L1175) it says "@param `channelNumber` - [byte] - The channel you want to change" Meaning you need to send this 1-8, not 0-7. 

  
  

  Tip: When you see "channelNumber" in the docs, that indicates that you should not zero index.
  

  
  

  Do you have github? I would like to make an example out of what you are trying to do and add it to the main repo!

  
  

  For channel 1, your code should look like:

  //Impedance

  board.streamSafeLeadOffSetForChannel(0x01, OFF, ON);

  
  

  Important to note you must be streaming for impedance to be measured.
• sardet

  November 2016

  Thanks @pushtheworld .

  I uploaded the whole library @ ;https://github.com/jpdandrade/OpenBCI_FirmwareV2

  
  

  In OpenBCI_FirmwareV2/DefaultBoard/DefaultBoard.ino, I added, on the setup() method, the line "board.streamSafeLeadOffSetForChannel(0x01,OFF,ON);" and below (commented) another option of code for impedance checking in the 8 channels. but none of the options did what I wanted.

  
  

  So, if you could make that example (how to automatically check impedance), it would really be great.

  Thanks!
• pushtheworld

  November 2016 edited November 2016

  Hey @sardet
  
  There is an open issue for this feature here https://github.com/OpenBCI/OpenBCI_32bit_Library/issues/39
  
  To better plan this out, please tell me what information you want back from the board on that issue page. In other words, what is your work flow? We can make this an API feature.
  
  We can allocate a stop byte for this data and send all the info in a packet or one channel at a time. Now that another person wants it, I will push to get this into 3.0.0.