FemtoBasic with 4GB uSD card?

Comments

• Mike Green Posts: 23,101

  2010-07-25 21:32 edited 2010-07-25 21:32

  Make sure you have the current FemtoBasic version (3.009) from the Object Exchange. The SD card driver was updated a few weeks ago to use Rokicki's FSRW 2.6. It's supposed to work with FAT32 as well as FAT16, so it should work with a 4GB uSD card.
• zappman Posts: 418

  2010-07-25 22:11 edited 2010-07-25 22:11

  Yes, have i have FemtoBasic version (3.009) from the Object Exchange
  
  The object contains fsrwfemto.spin with the comment v2.6a 3 June 2010 Modified to make compatible with FemtoBasic.
  
  When I try to access the card in FemtoBasic, by typing 'files' then return, I get a message 'Can't Mount SD Card'
  
  I am using the Parallax micro-SD Card Adapter (#32312)
  
  
  The program below works perfect so I think my wiring is OK.
  SD2.0 FATEngine Demo
  ¦
  ¦ Author: Kwabena W. Agyeman
  ¦ Updated: 6/2/2010
  ¦ Designed For: P8X32A @ 80Mhz
  ¦ Version: 1.0
  
  Visit Zappman's Blog at Savage Circuits
• Mike Green Posts: 23,101

  2010-07-25 22:22 edited 2010-07-25 22:22

  Do other uSD cards work with your setup and FemtoBasic?
• zappman Posts: 418

  2010-07-25 22:38 edited 2010-07-25 22:38

  I only have the one uSD card, so the answer is no I don't have any other uSD cards that work with my setup and FemtoBasic.
  
  I could buy another (smaller) card I guess.
  
  The card was formatted on a laptop if that makes any difference.
  
  Visit Zappman's Blog at Savage Circuits
• Mike Green Posts: 23,101

  2010-07-25 23:09 edited 2010-07-25 23:09

  I had only tried FemtoBasic with 2GB FAT32 uSD cards since I don't have any 4GB cards handy and it seemed to work. It may take 2 or 3 weeks before I have time to work on this. Thanks for letting me know. I'll have to get a set of larger uSD cards to test things more thoroughly.
• zappman Posts: 418

  2010-07-25 23:22 edited 2010-07-25 23:22

  Thanks for your help, I will try a 2GB Fat 32 uSD card.
  
  Visit Zappman's Blog at Savage Circuits
• hinv Posts: 1,252

  2010-07-26 16:05 edited 2010-07-26 16:05

  I believe any uSD card over 2GBm would be SDHC. I'm not sure what the difference is in accessing them though.
• localroger Posts: 3,451

  2010-07-26 17:44 edited 2010-07-26 17:44

  The difference between SD and SDHC is that in SD, when you request a block you specify its 32-bit starting address; this would give 4 GB but many drivers use signed math so they're limited to 2 GB. With SDHC you specify the block number. If you want to support both formats when booting the card you also need to check some registers to determine whether it's SD or SDHC; afterward the only difference is whether you shift the block number left before sending it to the card.
  
  You could support SDHC only just by eliminating the block number to address shift in the old driver.