How to set the address of a matlab variable (on an external target)

I use an external target with an stm32f4 arm board. On the target there is a buffer containing an image from an onboard camera. I know the absolute memory address of this buffer.

How can I access this variable from a Matlab function in my Simulink model? Think "var buffer@0x080000"

Is there a way to to this in Matlab? Thanks in advance, Sietse