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Function RTT_ERAM_MapBlock

RTT_ERAM_MapBlock maps a 4M block of physical Extended RAM into the virtual address space below 4G:

void * RTT_ERAM_MapBlock(RTT_ERAM_Handle Handle, int Window, int Block);

Parameters

Handle

An ERAM handle previously returned by RTT_ERAM_Alloc.

Window

Specifies which logical window is to be used, 0 or 1. Value 1 is only supported if flag RTT_ERAM_2_WINDOWS was specified when this Extended RAM set was allocated.

Block

The logical 4 megabyte block to map. This parameter must be in the range 0 .. RTT_ERAM_BlocksAvail(Handle)-1.

return value

A pointer to the mapped block.

If the Extended RAM set was allocated with flag RTT_ERAM_2_WINDOWS, the returned value can change with each call, even for the same logical window index. If flag RTT_ERAM_2_WINDOWS was not set, the return value will always be the same.

Function RTT_ERAM_MapBlock may not be called simultaneously by several threads with the same Handle parameter, not even for different logical windows. If more than 1 thread need to call RTT_ERAM_MapBlock with the same handle, the application must protect it with a critical section or mutex semaphore.

Extended RAM Management

Function RTT_ERAM_Alloc