| 摘要 |
PROBLEM TO BE SOLVED: To efficiently and surely update the program of a necessary circuit board without necessitating any work such as ROM exchange. SOLUTION: This picture forming device is provided with plural circuit boards for each function, and a flash memory for each circuit board. This flash memory calculates a check sum from a check code included in data (S2), collates the calculated check sum with a check sum for collation for judging whether the data are normal or abnormal (S3), receives data for rewriting from the outside part (S5), and executes the rewriting of the data (S7 and S8) when it is judged that the data are abnormal. |
