There is no limit to the number of systems an application can access; it is limited only by the physical devices present in your computer or accessible from your computer. To use multiple Matrox imaging boards, you have to allocate a MIL system for each board. If necessary, you can use MappInquire() with M_INSTALLED_SYSTEM_DESCRIPTOR + n to select the system to use at runtime.
To perform a processing operation, your source and destination buffers can be on different systems; MIL will transparently copy buffers to the most efficient of these systems, if necessary.
To exchange data between systems, you can physically copy the data from one system to another. The copy is always performed by the most suitable system. If both systems are of the same type, the copy is always performed by the destination system.
Instead of performing a physical copy using MbufCopy(), you can allocate a buffer on one system and use MbufCreate...() to access this buffer from another system. MbufCreate...() creates a buffer that maps to allocated mappable memory, for example, on the Host or any MIL system; no memory is actually allocated to this newly created buffer. This technique can be used, for example, to update a buffer (or part of it) with data grabbed from different systems. Note that after writing to the created buffer, you should notify the real buffer that its contents have been changed, by calling MbufControl() with M_MODIFIED. For more information about creating data buffers, see Chapter 19: Data buffers.
To grab, the digitizer and the destination buffer must be allocated on the same MIL system. Similarly, to display a buffer, the display and the buffer must be allocated on the same MIL system.
Windowed displays from different systems on the same computer will automatically display together on the same screen in different windows.