| 摘要 |
<p>PURPOSE:To attain the grade-up of an information processor by exchanging only a CPU by preparing a CLK and a READY signal under the considering of the access speed of a memory. CONSTITUTION:The signals of a CPU 401 and a CPU 602 are mutually connected except a few signals. When the CPU 602 is mounted on a socket, a signal 601 changes from 'H' to 'L'. Then, a CPU 401 turns a CPU output signal into a high impedance state according to the change. Thus, the output signal from the CPU 602 is validated for a CPU bus signal 604 instead of the signal of the CPU 401. Thus, it is possible to attain the grade-up only by inserting the CPU 602 into the socket.</p> |
