RTOS: windows ce : Real mode and protected mode memory accessibility overhead

I have a control loop between hardware and software using RTOS: windows ce.

I read data in from a device through Real mode. I process the data in protected mode, due to limited memory in Real mode. I then switch back to rea开发者_开发百科l mode to set another device based on results.

There is a lot of overhead in this and it slows things down. Is there a way to access the same memory on the heap? Is there a means of making this efficient so the overhead is at a minimum?

thanks

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Use the VirtualCopy API to map physical addresses into a process's virtual address space. There should be no need to drop down to real mode.