Help with SPI flash part...

[jonperrin]

Hi Isaac,

Thank your for your sample application. We have ported the code to the KL26

part. Instead of using the SD card we are trying to use spansion flash.

Its an 8MB part.

We have the composite device enumerating, however when we try to format,

read or write it fails.

Do you have any example that uses an external SPI flash device such as a

Spansion or Microchip part?

-jon-

Jon Perrin

Glacier River Design, LLC

Jon.perrin@glacierriver.com <mailto:Jon.perrin@glacierriver.com>

www.glacierriver.com <http://www.glacierriver.com>

425-829-4151

[mjbcswitzerland]

Hi Jon

To use the Spansion SPI Flash you need to add a block-management/wear-level layer to the code since it is not suitable for FAT (due to its large sector size). I have attached a document showing basic concepts for this.

You can also get such code from Spansion, which then needs to be ported/integrated in to the environment.

A potential difficulty is that this requires a certain amount of RAM for management - about 16k for 8Meg, which would possibly not be realisic for the KL26.

For a few MBytes SPI Flash and FAT on the KL26 I would consider Atmel AT45DBxxx types since their sector sizes are much more suitable. If you are not planning a lot of writing you could also choose to dispense with any wear-leveling layer, which then makes it very easy. There is standard KL26 support for this in the uTasker, as USB-MSD composite.

Regards

Mark

Kinetis: utasker.com/kinetis.html

KL26: utasker.com/kinetis/FRDM-KL26Z.html / utasker.com/kinetis/TEENSY_LC.html

For the complete "out-of-the-box" Kinetis experience and faster time to market

[xiangjun_rong]

Dear Jon,

Unfortunately, I have not the experience to use SPI flash. But I think you can configure the SPI module of Kinetis, output the SPI signals to oscilloscope then compare the SPI signal with the required SPI timing in data sheet of flash. Follow up the flash instruction to erase/write/read.

BR

XiangJun Rong