| 摘要 |
<p>PURPOSE:To set data output for a special address to flowing by avoiding a decrease in yield due to malfunction of an unused area. CONSTITUTION:The read only memory comprises an address input buffer 1 in which read address is input, a Y decoder 2 for selectively decoding an address from the buffer 1 and outputting it, a X decoder 3, a memory cell-matrix 4 for outputting data through an address signal to be output from the X decoder, and a Y selector 5 for selectively outputting special data from a data signal to be output from the matrix 4. The memory further comprises a final address ROM 7 for storing a final address value in the matrix 4, a comparator 8 for comparing an address value to be input from the buffer 1 with a final address value to be input from the ROM 7 and outputting a predetermined decision signal if it exceeds the final address value, and a controller 9 for outputting preset special data to an output buffer 6.</p> |
