Hi, I work on ST10F168 with 6M*16bits external ram. This external Ram is used by the microcontroller and a xilinx, so the datas and adress bus are divided by 2 chips. I would to know if i can put POL & POH & P1L & P1H & P4 in tristate mode when the xilinx is accessing external Ram. Can i do this manually by software or using HOLD,HLDA,BREQ signals with logic combination? I see this signals work automatically but i don't know if it work with another chip. If it can, how does it work? Thanks Regards