| 摘要 |
<p>PURPOSE:To decide a condition on a hardware basis by constituting a titled microcomputer so that one of two kinds of start addresses of a program counter can be reset in accordance with whether the pulse width of a reset signal is large or small. CONSTITUTION:A reset signal supplied to an input terminal 1 is applied to a pulse width deciding circuit 3 after a noise has been eliminated through a reset signal validity deciding circuit 2. This pulse width deciding circuit 3 compares a prescribed reference value Th and a pulse width T of said inputted reset signal, and in case of T>Th, the first deciding signal 4 is outputted, and in case of T< Th, the second deciding signal 5 is outputted. A program counter controlling circuit 6 controls a program counter 7 so as to be initialized to a start address PC0 and a start address PC1, when the first deciding signal 4 is inputted, and when the second deciding signal 5 is inputted, respectively.</p> |
