| 摘要 |
PURPOSE:To prevent rewrite of a written data by providing a write suppressing means to a memory chip written in already in writing to a memory comprising plural memory chips. CONSTITUTION:In writing a data to the memory 1 (M1-M16), a control section 2 outputs a data D, write signal W, chip selection signal C and a pulse P. While an address counter (10<6>-adic) 3 is driven by the pulse P, the address of the memory chip M1 is selected sequentially and the data D is written. When an address counter 3 counts out, a carry signal C is outputted and fed to an up terminal UP of an up-down counter (hexadecimal) 14. Thus, a signal level at the output terminal E1 of an AND gate G1 goes to ''0'' and the write is inhibited to the memory chip M1. |
