I'm using the Cyclone V SOC with a 128 bit F2H_SDRAM bus. Notes: 1. I had to build a new pre-loader to make this bus work. 2. My design doesn't communicate with the F2H directly - instead I use an Avalon Clock Crossing Bridge. Most of the time - everything functions correctly and I transfer data successfully to the HPS's SDRAM. However, once I increase the amount of written data over a certain amount - the "WAITREQUEST" signal of the Avalon Clock Crossing Bridge goes high (as observed with Signal-Tap) and never returns back to '0'. What can be the cause ?