| 摘要 |
<p>PURPOSE:To convert the mask option setting operation into a programmable form by using a mask option program means which works as prescribed in a writing mode and a non-writing mode of a program memory. CONSTITUTION:A mask option program means contains an extended address decoder 107, an extended memory part 111, an extended memory decoder part 115, mask option setting circuit 116 and a data writing control input 117. Then the program means stores the setting data on the mask option in the part 111 in a writing mode of a program memory 106 and then supplies the stored setting data to the circuit 116 in a non-writing mode respectively to perform the prescribed setting operation. Thus a mask option setting operation can be converted into a programmable form.</p> |
