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yj

yj

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yj
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France , Bordeaux
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Location
France , Bordeaux
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  • Hello all, @wjcroft : the "SD card Only"  present on github,   has been writen by Joel.    It has been for me a starting point from which I increased the sample rate and I suppressed overruns. @Rogerio : Most operations on the OBCI Card , are cont…
  • Yes @biomurph, the Host on the Dongle and it works very well when I choose the channel of another one  of our 3 new Cards... A last symptome : If I try to upload the firmware of the Card, as I use to do, the blue diode whick blinks slowly after the…
  • @biomurph , @wjcroft , "One train may hide another" and a  problem , another... I Uploaded the Host Firmware to the Dongle following the instructions:     32 bits Host...          device_t    role                  =   HOST   ;          RFduinoGZL…
  • Ah!!! Sorry David , I thought you wanted to not to use a booster... This graph is the typical  way the voltage of a 1000mAh Lipo, decreases with the capacity used. At 80% (800mAh used) any lipo shows this "cutoff" as you say.   Yannick.
  • You make me doubt, David,on http://docs.openbci.com/hardware/01-OpenBCI_Hardware#openbci-hardware-documentation-openbci-32bit-board-openbci-32bit-board-circuit-schematic the +3V regulator outputs 3.3V. 3.7V  is the voltage at the end of the dis…
  • Hello David, I asked myself the very similar question... Theoreticaly Yes. From the  LP5907 data sheet : 7.4.2 Minimum Operating Input Voltage (VIN) ...  The output voltage is not regulated until VIN has reached at least the greater of 2.2…
  • Have you choosen te rigth Card in "tools/Cards" menu ?
  • @biomurph , @wjcroft , Following your recommandation I finally compiled the Dongle code... My problem was that I forgot to choose in "Tools/Board"  Rfduino , causing to appear the error message : OpenBCI_32bit_Host.ino:35:53: fatal error: …
  • @biomurph, yesteday, using windows 7 I remarked that the "+" are no longer needed ! ! ! Thus the ++ problem that I observed under XP, would not be caused by the Dongle itself ? Have you ever heard of a such incompatibility?   Yannick.
  • Thank's @biomurph, My english is bad..., I just wanted to know if the two versions , 1.5.8 and 1.6.5 can be installed on the same computer ? & sorry again...    Yannick.
  • Thank's @biomurph, Then can it coexiste with the 1.6.5 that I curently use?  Yannick.
  • @biomurph I am trying to re-program the Dongle.    But : OpenBCI_32bit_Host.ino:35:53: fatal error: RFduinoGZLL.h: No such file or directory Do I absolutely need to use the 1.5.8 ide ? If yes can it coexiste with the 1.6.5 that I curently use? …
  • @biomurph Good news, what has been your motivation ? - Overruns ellimination? - Sample rate increase? - Background task? - ... ? In any case ,  a big thank !!!   Yannick.
  • @biomurph you asked me if I had altered the dongle firmware... Do you mean that someting could be wrong with this dongle? What should I do? Is there anything to check? How? Is there a way to know which version is running? Thank's Yannick.
  • @ntlanh Do not worry Anh,   8 times faster and shorter @ 2kHz,      is well related to "the speed of writing the data from the Board to the SD card."   Yannick.
  • @wjcroft & @ntlanh, & ... yes interrupts is the best approach. I hesitated to use them because I was afraid to break some time dependent processes during SD card writing... For exemple is it possible to interrupt and release the SPI bus d…
  • @ntlanh, no, no. 5 minutes corresponds to 11.000 blocks at 250 Hz. That should do   37.5"   at 2k Hz. at 2k Hz it is 8 time faster and shorter. to acquire these 11.000 blocks A block = 512 octe, in the 5mn_file you should find about : 5x60x250…
  • @ntlanh, To write one-second data , at 250Hz or 2kHz ,   it takes one second. (Joke). When you choose to record at 250Hz for 5 minutes you record 11000 blocks... at 2k of coarse it will take about 5'/8  or 300 secondes / 8 ... to get these 11000 …
  • @ntlanh, I sent you a dropbox link. Tell me if you can use it... Yannick.
  • hello Ntlanh, @ntland, 1) the files that you receive by bluetooth or from the SD card ? 2) On the SD card the Footer is written in the last  block of 512 octes,  which is filled with zeros. 3) When you choose a "record duration" in fact the soft…
  • @AgustinS I ,   for my part ,   fully agree with your interpretation of the Sandwich protocole and its timing. On the net the best I found was :     Yannick.
  • @biomurph Thank's for your answer, - I have not touched the Dongle firmware. - In the file OpenBCI_32bit_SD_Only.ino   After the main loop we find : // =============== some variables to help find 'burger protocol' commands int plusCounter = 0; …
  • Hello all, @biomurph, "The Dongle inserts the '+' sign into the signal. You, or the controlling program, does not have to do it." It seams logic but I cannot get any reaction of the programme if I dont write all the "+". From the Arduino IDE, wh…
  • A last modif : The SD only version of Biomurph uses the code "N" to start running. In the file   "OpenBCI_32_SD_Only.ino" you will find a case 'N'  : In this case I added the initialisation of write and read indexs.       case 'N':        writeTo…
  • @wcroft Thank's William,    but "it is too early to crow victory"... To do what I want this code works but since it depends on the context and the type of SD Card, it should be tested carefully... For exemple I am not sure that 16 Channels / 2kHz…
  • //============================================================================================================    //  In File     SD_Card_Stuff.ino  ***** Call to overloaded writedata function in order to call OBCI.push() during SD busy state *****…
  • Hello, @wjcroft, Thank's again William,  again I missed  the link to the comments, for my defense recognize that this link is rather discreet... I am impatient to know the details which will appear in the FAQ.  Yannick.
  • Hello, @wjcroft Thank you William, I missed the first link... The aim of the second link is not related to the problem raised by the very long "busy state" of the SD interface... ( @hitheshaum : have you tested it recording on a SD card?  (Since …
  • Concerning the overruns, I did some statistics ; on the following figure on X axis the acquired sample number, on Y axis the number of samples losted during overruns. The session duration was 130' and the sample rate 500Hz on 8 channels. There is …
  • Yes in this card it's the war for the "SPI". I wonder if this achitecture has been kept in the new card called "Ganglion". Will you clone it? Any way even if we have a dedicated spi for the sd card, even if we use interrupts instead polling, (it wo…