Hello everyone,

i am currently trying to get a mobile sdram sodimm (144pin, 100MHz) running with my custom AT91SAM9XE512 board. The databus width is 32bit out of the supplied 64bit (dqmb4..7 tied to 3V3), the full schematic is attached.

sam-ba fails with following output:

-I- Waiting ...
-I- TCL platform : Linux
-I- SAM-BA CDC 2.10 on : linux
-I- Connection : /dev/ttyUSB0 (target(comType) = 3)
-I- Board : at91sam9xe512-ek
-I- Traces Level : 4
-I- target(handle) : file5
Read device Chip ID at 0xfffff240 --- get 0x329aa3a0
-I- Found processor : at91sam9xe512 (Chip ID : 0x329aa3a0)
-I- External RAM Settings : extRamVdd=1, extRamType=0, extRamDataBusWidth=32, extDDRamModel=0
-I- Loading applet isp-extram-at91sam9xe512.bin at address 0x300000
-E- Error during external RAM initialization.
-E- External RAM access is required to run applets.



I tried different memories, some with 8, some with 4 chips as i suspected the ebi could not drive eight chips in parallel (capacitive load), still no luck.

Do any of you fine gentleman have further ideas?

>>Do any of you fine gentleman have further ideas?

Wow, I'd be surprised if that works. As far as I'm aware this CPU will only support TWO 16-bit wide SDRAM chips (total max 256MB), and you'd need to custom program the SDRAM controller with the correct bank,row,column and refresh for the chips being used. ie It doesn't magically figure this out by reading the EEPROM on the SODIMM.

[quote="CptTitanic"]Wow, I'd be surprised if that works. As far as I'm aware this CPU will only support TWO 16-bit wide SDRAM chips (total max 256MB), and you'd need to custom program the SDRAM controller with the correct bank,row,column and refresh for the chips being used. ie It doesn't magically figure this out by reading the EEPROM on the SODIMM.[/quote]

That would indeed be a bit much, but i checked with the specification:
http://codepoet.org/ram/sodm1_0.PDF

for example my 8-chip, 64MB sodimm has:
12 rows, 2 banks, 8 cols

with this input i thought i just need to change
sam-ba_cdc_linux/applets/at91lib/boards/at91sam9xe-ek/board_memories.c
and recompile.
But there seems to be a hardware issue.