Memory Overlap

[mangesh]

Posted on June 26, 2003 at 22:07

Memory Overlap

[mangesh]

Posted on May 17, 2011 at 11:54

Hi,

I have a question about overlapping memory maps. The memory map of my system looks something like: Legend: MF =Main Flash SF=Secondary Flash MF == 0x000-0xFFF (page 0) 0x000-0xFFF (page 1) SF == 0x000-0xFFF SRAM ==== 0x2000-0x3FFF I am not able to program (write) to the MF (in data space only) executing from the SF (in program space only) with this memory map in spite of setting the VM and PAGE register values correctly. However if I setup the system with unique address, I am able to acheive the writes. I have inherited an older application and need to use the memory mapping mentioned above. My understanding was that, in this case, all memory write accesses (except in the range 0x2000-0x3FFF) should be sent to the MF even though it has the lowest priority because those addresses don't exist in the SRAM and the SF is in program space. Why can I not write to the MF? Do I need to do something more before I try to write? I using the Keil compiler and most of my code is in 'C'. Thanks.[ This message was edited by: uPSDude on 26-06-2003 20:10 ]

[joseph2399]

Posted on May 17, 2011 at 11:54

If your Main Flash is mapped to 0-0xFFF, then there is no memory overlapping with SRAM which is mapped to 0x2000-0x3FFF right? If your Page and VM registers are setup correctly, your should be able to write to the MF after the unlocking sequence. You may want to take a look at our design example 2 dk3200_dsn_2, which has some Flash write examples.

[mangesh]

Posted on May 17, 2011 at 11:54

Oops, the memory map acutally looks like:

MF == 0x0000-0xFFFF (page 0) 0x0000-0xFFFF (page 1) SF == 0x0000-0xFFFF SRAM ==== 0x2000-0x3FFF I will look at the examples anyway. Thanks.