SD Card OTA problem

karios · **Joined:** Thu Nov 24, 2011 2:42 pm **Posts:** 3

Hello,
I've just purchased 50 2GB SD cards for use with my Waspmotes and discovered that all of them report 1.83GB of free space. The make of the SD cards are Transcend. The official specifications of the Waspmotes indicate that they should work. The forum entries I read indicate that they will not.
Am I to believe that because you are using a different library when using the SD card to store data and when using OTA programming, I have to throw away 50 perfectly good SD cards? Are there any plans to just support perfectly good and valid SD cards that you did not provide, since there is a standard SD card reader on the Waspmotes you sell? You seem to know how to avoid "bad blocks" while writing, although I highly doubt that ALL 50 of my SD cards have bad blocks. It is clearly a different problem.
It was bad enough that I discovered it was not possible to even do OTA programming without an SD card installed, today I discovered that the SD cards I bought are not usable because I didn't buy them from you?
After discovering other not-so-nice things about the Waspmotes I bought (like for example that I have to physically remove the XBee modem in order to just update the firmware since the modem and USB use the same channel) this does it. There are two many weird things with these motes that I've never seen in any other brand, and I've used TelosB, iSense and MicaZ in the past with no such weird behaviour and special requirements.
So please, fix the OTA libraries so that I can use my cards and develop a workaround for programming my motes without removing the modem every time.

AmroQuandour · **Posted:** Thu Nov 24, 2011 3:52 pm

I am not using Waspmote's SD cards and OTA is working fine. Just follow the instructions in the manual. Try them out. and most likely they will work !

karios · **Joined:** Thu Nov 24, 2011 2:42 pm **Posts:** 3

AmroQuandour wrote:

I am not using Waspmote's SD cards and OTA is working fine. Just follow the instructions in the manual. Try them out. and most likely they will work !

What is the brand of your SD cards? How much space do they report on Windows Explorer? According to this, if they report 1.86GB they work fine but mine do not (they report 1.83 on Windows and according to Libelium, they contain "defective blocks". All 50 of them.
I think you were just lucky to get SD cards with the memory chips that Libelium likes.

libelium-dev · **Joined:** Mon Sep 28, 2009 1:06 pm **Posts:** 7455

Hello karios,

We are sorry to hear that, we hope your retailer lets you change those cards for other ones.

Of course, any client is NOT obliged to purchase the SDs that we offer, in fact many clients preffer to purchase the SDs by themself.

But obviously, we cannot assure the correct working of any item that we have not tested. It is not our responsability to give support or warranty for any hardware or software that does not come from Libelium.

Our SDs always work; not because they are special, but because we have tested them before. We do not want to charge anybody for something that he can already have, but not all the SDs he has will work fine. As you say to Amro, the different types of SDs is not something Libelium can control.

The only way to be 100% sure that the cards will work is to purchase them from us, this is what we mean in the Technical Guide, chapter 1.3:
http://www.libelium.com/support/waspmote

Best regards

karios · **Joined:** Thu Nov 24, 2011 2:42 pm **Posts:** 3

I am still trying to get to the bottom of this.
In SDVolume.cpp, when we do init of the SDVolume class, it never gets any information from the SD Card. More specifically, Total Sectors, First Sector everything is 0 all the time. I don't think this has something to do with bad sectors, it's a different problem. We added some debugging messages to see the values of everything related to the SD card as follows:

Code:

    part_t* p = &cacheBuffer_.mbr.part[part-1];
        
    if ((p->boot & 0X7F) !=0  ||
      p->totalSectors < 100 ||
      p->firstSector == 0) 
        {
      // not a valid partition
        
          USB.println("Error: SdVolume::init() Invalid partition, (Total Sectors, First Sectors, boot), ");
        USB.println(p->boot, DEC);
        USB.println(p->totalSectors, DEC);
        USB.println(p->firstSector, DEC);
          return false;
    }
        volumeStartBlock = p->firstSector;
  }
  if (!cacheRawBlock(volumeStartBlock, CACHE_FOR_READ)) 
  {
          USB.println("Error: SdVolume::init() Cache for read2");
          return false;
  }

  bpb_t* bpb = &cacheBuffer_.fbs.bpb;
  if (bpb->bytesPerSector != 512 ||
    bpb->fatCount == 0 ||
    bpb->reservedSectorCount == 0 ||
    bpb->sectorsPerCluster == 0) 
  {
       // not valid FAT volume
      USB.println("Error: SdVolume::init() invalid FAT volume, (BytePerSector, fatCount,reservedSectorCount,sectorsPerCluster)");
     USB.println(bpb->bytesPerSector, DEC);
     USB.println(bpb->fatCount, DEC);
     USB.println(bpb->reservedSectorCount, DEC);
     USB.println(bpb->sectorsPerCluster, DEC);
      return false;
  }

Any ideas on this?

libelium-dev · **Joined:** Mon Sep 28, 2009 1:06 pm **Posts:** 7455

Hello karios,

We do not really think that the problem can be solved via sw.

You can purchase certain models of SD that just do not work on Waspmote. Also, you can purchase the same model, and one batch will work and another won't.

Best regards