Current State of Writing to SD card

rjo_

I'm an idiot... I admit it. You guys have been busting your backsides to offer the latest and the best, and I haven't even kept up with the conversation.

So... for anyone interested, what is the current state of the art in writing to SD cards?

What is the fastest that can be achieved, where is a snippet of code showing how to do it?

Thanks,

Rich

localroger

If you're looking for performance, it's fsrw 2.6.

If you're looking for bulletproof usability and complete features, look for Kye's thread "everything and the kitchen sink." It's still a work in progress but coming along.

If you're looking to conserve Hub RAM, it remains sdspiqasm from fsrw 1.6. I am using that as the basis for most of my current personal stuff. I suppose it might be a good idea sometime to post my reworked commented version of it for people who want to add features...

rjo_

Thanks, I'm using fsrw 1.6. I ran out of room, so I've off-loaded the SD-card writing to a different Prop... Now I'm looking for performance.
I'm writing one byte at a time, which is part of my problem... but I have no idea how to write a block at a time... where can I find a code snippet for this?

Rich

rokicki

Use pwrite()/pread() rather than pputc()/pgetc() and that should take care of it.

You need to minimize your per-byte overhead.

If you need help, feel free to share more about what you're doing and perhaps even some code.

lonesock

rokicki said...
Use pwrite()/pread() rather than pputc()/pgetc() and that should take care of it.

You need to minimize your per-byte overhead.

If you need help, feel free to share more about what you're doing and perhaps even some code.

Just a quick addition to this, make sure your buffer that you use in pwrite/pread is both long aligned, and a multiple of 512 bytes. [noparse][[/noparse]8^)

Jonathan

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lonesock
Piranha are people too.

rjo_

uh huh[noparse]:)[/noparse]

I'll be back[noparse]:)[/noparse]