| 摘要 |
<p>PURPOSE:To effectively use the input terminal of a microcomputer by a simple device by selecting and inputting an external input signal or a parallel bit signal by switches controlled by the microcomputer. CONSTITUTION:When a microcomputer 1 inputs the external input signal from external input terminals IP0-IP7, the external signal is given through diodes D10-D17 and resistors R10-R17 to the bases of TRTR0-TR7. When an 'L' signal is given to a terminal IP0, the TRTR0 is made ON, an 'H' signal is led out on a line L0. Next, when the computer 1 inputs the parallel bit signal set by the diodes D0-D7 through a TR10 and a 11 to operate as switches, the computer 1 outputs a '1' signal from an output terminal DOUT 1 and a '0' signal from an output terminal DOUT 2 and thus, the external signal can be inputted.</p> |
