11-28-2011 12:23 PM
Hi,i have a problem with the address calculation of the pipeline bridge. I'am using Quartus 10.0 Sp1 and SOPC Builder. To increase the system frequency, i want to use a pipeline bridge tha is connected to a tristate bridge. the tristate bridge is connected to three memories. ( See attachment ) Flash : 0x00000000 .. 0x03ffffff (64 MByte) SRAM : 0x04000000 .. 0x040fffff ( 1 MByte ) FE-RAM : 0x04100000 .. 0x04101fff ( 8 KByte ) The "Base Address" from the Pipeline Bridge is 0x00000000 ! SOPC Calculates the "End Address" 0x07ffffff. Why ? I expect that the "End Address" must have 0x04101fff. Can anyone explain the address calculation of the pipeline bridge ? Thanks,
11-28-2011 01:53 PM
This is from chapter 11 of Quartus Handbook (Avalon Memory-Mapped Bridges):"The address span of an Avalon-MM bridge is the smallest power-of-two size that encompasses all of its slave’s ranges."
12-02-2011 10:00 PM
Thank you for your answers.Ok. Any Bridge, (Clock Crossing or Pipeline) delivers a new Master Port to the Components that are enclosed from the Bridge. If i want to Address (64 MByte + 1 MByte + 8KByte), the Master Port needs 27 Address lines to access all slave addresses. 2^27 = 128 MByte = 0x07FFFFFF Result: The Address Range for my Pipeline Bridge is 0x00000000..0x07FFFFFF I have to think better soon ;-)