Control method of image memory

Abstract

Abstract PURPOSE:To improve the use efficiency of an image memory by allocating a common storage place in the image memory previously when image data is ''0'' and an individual storage area when image data is not ''0''. CONSTITUTION:When a cell C11 on an image map M is transferred, the address corresponding to the C11 is set in a storage virtual address register 14 by a command from a CPU10 and a non-zero detecting circuit 13, on the other hand, outputs no interruption signal because the C11 is ''0'', so that the flag F of entry in an address conversion table 15 corresponding to the C11 is still ''0''. Then, an address converting circuit 17 decides that allocation is not performed judging from the flag, and converts a virtual address in the register 14 into a specific address among unallocated cell address 16 to inform a data transfer part 12 of the address. Consequently, the image data of the cell C11 is stored in the storage cell K in the image memory 4 corresponding to said specific address.

Inventors

• 👤 Shunsaku Fukunishi
• 👤 福西　俊策
• 👤 Yasukatsu Oka
• 👤 岡　安克
• 👤 Takayuki Ishizu
• 👤 石津　隆幸

Bibliographic Details