Hello,

KernelVersion 2.6.24.3

I try to use the at25 EEPROM driver included in the kernel.

I add the following lines to my boardsam9260ek.c file:


I want to use the SPI EEPROM at SPI0_CS2 -> Pin PC16

If I choose this Chip select the kernel hangs on booting -> no message just stop !

Could anybody explain me, what´s wrong ? If I use Pin PC17 (.chip_select = 3) same Problem...

If I try .chip_select = 0 or .chip_select = 1 (PA3 or PC5) it seems to work ?

Thank you for your help.

Manuel Sahm

try :
1) if this pins (PC16 , PC17) defined or used somewhere else;
2) use osciloscope to see any activity;
3) try osciloscope on CS, CLK, DI, DO - posybly sync. problem ( i had some timing problems with my AT25256W)
4) if interesting - got driver for AT25256W (use with AVR ATMEGA 128), work's on any pin you chose, some code modification and you got external memory runing.

GL

Hello,

I found out the problem,

PC16 and PC17 are used for the SDRAM Data lines....

I have to choose CS_0 (PA3).

With this configuration it seems to work.

Another problem:
---------------------------
How can I write/read to the eeprom ?
The code fails:

the file exists but I get fd = -1

What´s wrong ?

Thank you

Probably instruction set problem, try to fin source code for othe EEPROM and compare it, diferent EEPROM, especialy SPI has diferent memory maping and instruction set (check data and command exchange protocol for your EEPROM), also pay atantion at your reading and writing mode's (page read/write, byte read/write), and final - chaeck Write Protect and "hold" pin's.

GL

Found out the problem:

you have to use:


then it works,

now use: fseek, fwrite, fread, flcose to access the eeprom.


Best regards

Manuel