Patent ID: 7797586

Claim:
An image forming apparatus, comprising: a processor; storage means, coupled to the processor, for storing a computer program; a volatile memory, coupled to the processor; a non-volatile memory, coupled to the processor, for storing information about an area targeted for error-checking, the information indicating one of a plurality of memory blocks into which the whole memory area of the volatile memory is divided; and a display device, coupled to the processor; wherein the computer program causes the processor to perform the steps of: (a) executing error-checking on an area indicated by the information at every power-on; (b) updating the information so as to complete the error-checking on the whole memory area of the volatile memory in a plurality of times of power-on; and (c) if a memory error has been detected, displaying information thereof on the screen of the display device, wherein the area targeted for the error-checking is a group of ‘m memory blocks (m<n) which are away from each other and are selected out of ‘n’ memory blocks into which the whole memory area is equally divided, the ‘n’ memory blocks being grouped into ‘k’ groups (k>=2) so that each group does not overlap to any other group, wherein in step (b), the computer program causes the processor to update the information about an area targeted for the error-checking so as to shift error-checking one of the ‘k’ groups sequentially at every power-on wherein the non-volatile memory further stores information which indicates a number of total power-on times and information which indicates a setting of the number of total power-on times, and wherein in step (b), the computer program causes the processor to perform the steps of: (b1) updating the information which indicates the number of total power-on times at every power-on; and (b2) if the number of total power-on times is more than the setting of the number of total power-on times, executing the error-checking on one group out of the ‘k’ groups, and updating the information about an area targeted for the error-checking so as to be shifted sequentially at every power-on.