yanqi su

problem with MCF5208 interfacing with 64M 16-bit Width SDR SDRAM

Discussion created by yanqi su on Apr 18, 2007
Latest reply on May 6, 2009 by Edison Tran
i try to develop a board using MCF5208 and ISSI IS42S16400(64M-bit,16bit width SDRAM).
I found a very strange issue :
when i  try to change a data in the SDR ,another address will changes accordingly.
The address is the current address + 256
for example,
When I write a 0x0002 to 0x40000000,   the  data at 0x40000200 will change to 0x0002
my schmatics follows the illustration on Page 317 Figure 8-2 of MCF5208RM.
Your help will be highly appriecated .
Thanks a lot