| 摘要 |
PURPOSE:To judge the normal/defective condition of stored and held data with an inexpensive device cost by calculating the block check character of the stored and held data when a power source is applied, and comparing it with the block check character stored and held separately. CONSTITUTION:Data is received and it is stored in the data storage area 14a of a memory 14, and also, the block check character BCC is calculated from the sum of bytes of received data, and the BCC is stored in a BCC storage area 14b. The check processing of stored data is started by applying the power source, and the data stored and held in the data storage area 14a is loaded on a BCC calculation checking device 15, and the BCC is calculated from the sum of the bytes. And stored and held BCC data is loaded on the BCC storage area 14b of the memory 14, then, it is compared with a calculated BCC. Thereby, it is possible to obtain required processing speed and reliability, and to reduce the device cost less than a case where a parity bit for checking stored and held data is provided. |
