I have a custom board with a K10 and an external RAM memory of 1M bytes (1Mx8) from Cypress. I was able to setup and access the memory range starting in 0x60000000, I can write and read any address without problems, looked like fine. I am using the flexbus with processor expert for setup. I am using 8 bits byte width connected to FB_AD 31 thru 24 and addresses from FB_AD 0 thru 19, control pins FB_CS, FB_OE, FB_WR, Cypress memory dos not require more than this. It is just the simplest stuff.
So the problem starts when I try to access the addresses writing and reading in a sequence in a loop of 256 steps. The loop is sequential starting in 0 thru 255 with base memory of 0x60000000, with external bus clock of 6MHz. It writes and reads but with 3% of error, that means I write one thing and read another, and it is random too.
Did anyone have this issue before? Any help would be appreciated.