*** error 65: access violation at 0x20080000 : no 'write' permission

Hi,
I am trying just a simple code for DMA test program for MCB1768 ref Board.
SRC ADD = 0x2007C000
DST ADD = 0x20080000

In simulation mode
it was saying error:
*** error 65: access violation at 0x20070000 : no 'write' permission
*** error 65: access violation at 0x20080000 : no 'write' permission

I have checked IRAM2 in project option. 0x2007C000 and size 0x8000

then in simulation mode it shows only

*** error 65: access violation at 0x20080000 : no 'write' permission then
i have mapped memory

MAP 0x20080000, 0x20081000 READ WRITE

then

It shows *** error 65: access violation at 0x50004008 : no 'write' permission
this address belongs to dma control configuration register.

then i mapped
MAP 0x50004000, 0x50005000 READ WRITE

then finally i got the error free simulation but i did't get memory data transfered from
SRC ADD to DST address.

first time i have faced this issue of "access violation " .
Then keil show map all the memory region specified for processor .
I should not be set by user to feed manually.

Please do help me .
If i am wrong i would love to hear some suggestions.

Regards,
Vikas Pandey