Hi all: I implemented memory tests in my bootloader code for the AU1500. I'm trying to figure out why Linux boots when loaded into cached KSEG0 (0x 80c0 0000), but my memory test FAILS for this same region. (pretty backwards huh? get linux booting, then write memory tests!) I start by writing 0x5555 5555 to all of uncached memory, reading it back, and I write 0xAAAA AAAA to all of uncached memory and read it back. This works great. Next, I try to write 0x5555 5555 to cached KSEG0 memory, and it fails at addr 0x8000FE50. But Linux boots! I'm not issuing SYNC commands when writing to cached memory; could this be the problem? We've exhaustively verified the memory burst parameters, etc. They look good. Thank you in advance for your ideas! Regards, Jeff -- Jeffrey Baitis - Associate Software Engineer Evolution Robotics, Inc. 130 West Union Street Pasadena CA 91103 tel: 626.535.2776 | fax: 626.535.2777 | baitisj@evolution.com