Go Down

Topic: What kind of board/shield do you guys want? (Read 5 times) previous topic - next topic

robtillaart

Quote
I'm new here, I willing to design and build some custom arduino pcbs.

And,  allready building something?


Yet another idea: Dual drive shield
- 2 SDCards
- 2 disable switches - NONE, A, B, AB/BOTH - (disconnect the SS pins)
- 2 LEDs to indicate active
-

Goal: replace one while the data is written on the other one - hot swappable discs

Possible other use:
- speed up logging by writing alternating to the disks ?
- ....
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

liudr

I've heard about the sd card library being slow. What is the reason? I thought sd cards on PCs are decent speed. You can't expect sd card to be as fast as hard drives, right? Will it help to have a dedicated MCU to operate sd card on a shield so the arduino can just dump data and move on to the next task while the MCU processes all the sd card IO?

billcramer07

Maybe this is too far out in left field but I would like to see a UNO type board with a mega2560 on it. Make the 3 serial ports available thru a right angle header on the edge of the board. A4 & A5 would become a dedicated I2c bus. Change the ICSP pins to match the 2560 pins. I don't need lots of I/O but I do need serial ports. Software serial is not a good option...

just an idea.

extent


I've heard about the sd card library being slow. What is the reason? I thought sd cards on PCs are decent speed.


PCs talk to SD cards via a 4bit parallel protocol which is well supported and performs well.  Arduino projects tend to use the serial interface which apparently can vary quite a bit in performance from it's parallel counterpart.  Not helped at all by the fact that the Atmega can't clock as fast as a SD card is capable of.

Go Up