Expansion on Register Address Space of VXIbus Device and It´s Application

To the size C VXIbus model, it´s PCB (printed circuit board) is large enough to bearing several function circuit. But the A16 register based slave device only has 64 bytes address space to be used as operation registers and special registers. This paper gives a simple technique to expand the register address space, which was being used in special VXIbus module for testing missile. The external memory´s addresses are mapped to specific offset address of VXIbus device, by using the internal logic of CPLD circuit. The VXIbus master controller can access the expanding address space by reading or writing the specific register. Timing simulation result of the logic circuit provides evidence for the design project. The realization and simulation results are presented, which proved that the method can solve the lack of register addresses effectively. Also, it is easy for practice, comparatively universal and very practical.