| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a microprocessor for allowing the word length of an outside ROM to be surely recognized. SOLUTION: When a device in which the word length of an outside ROM 1 is 8 bits or 16 bits is used, a logical value '1' or '0' is preliminarily written in the specific address of a flash memory 13. At the time of power supply of a microprocessor 2, a logic circuit 14 inside an identifying circuit 12 designates the specific address of the flash memory 13, and identifies the logical value read from the specific address of the flash memory 13. When the logical value is '1' or '0', a program counter 3 and an instruction register 5 are controlled so that the word length of the outside ROM 1 can correspond to the case of the 8 bits or 16 bits.</p> |
