RE: DDR ram issue using MCF54450 @240Mhz

Hi all

More to report my actual problem appears to be cache I have disabled icache and u-boot seems to be working as expected. If I type (icache on) the system locks up. Anyone know if this symptom is telling me something I need to look at such a layout other variables ect.

Gregg

METRONICS /// 30 Harvey Road // Bedford, NH 03110-6818 / US

We have a MCF54450 running at a CPU CLK of 240Mhz. we are using U-Boot  1.2.0 our design is using 1 16 bit Flash a PC28F256P33B85 BGA64. We are executing code in Flash and have written a DDR-ram test walking ones and walking zeros and address and address this will run for days at a time billions and billions of writes and reads.

When we move this to DDR-ram which is a MICRON MT47H64M8CF-3:F which we use two of on SD-16 through SD-31with SD_A0-SD_A13 and

SD_CS

SD_DM2

SD_DQS2

SD_DM3

SD_DMQS3

We cannot run code we are using the same settings as the Reference design the same chips. I have layed out the board with mentor and have put restraints in all of the lines to keep them within .4 inches in length.

The symptoms are it either gets an exception out in space or locks up before it gets to NET: functions

Anyone have any thoughts about the issue.

Gregg

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