| 摘要 |
<p>PURPOSE:To execute a diagnosis at a high speed, and to detect an undetected fault of an address line by reading out image data of an image memory determined in advance and image data of other image memory by a corresponding picture element unit, comparing them, and executing logging. CONSTITUTION:In order to prevent undetection of an error generated due to a fault of an image memory 11, the same image data is written on an image memory 12 at every picture element from a host computer, and the image data is read out of the memory 12 under the control of read and write controllers 3, 2, and written on the memories 13...11. Thereafter, the image data is read out of the memory 12 at every picture element under the control of the read controller 3, and the image data is read out for every corresponding picture element in order of the memories 13...11. Both these image data are compared by a comparator 15, and in case of dissidence, its signal is held by a latch 19 through an AND gate 17, and thereafter, stored successively in an error information storing part 141, and discriminating information of the comparison dissidence and a memory address are stored in a memory discriminating information storing part 142 and an address storing part 143.</p> |
