| 摘要 |
<p>PURPOSE:To optionally select pull up and pull down of an input terminal and to enlarge an application range by setting a constitution in such a way that the pull up and pull down of the input terminal of an input circuit can be selected by a program. CONSTITUTION:The input circuits 1a-1n are constituted in such ways that they are provided with input terminals 11 which input one among data INa-INn having prescribed level in an active state, input amplifiers 12 which input data from the input terminals 11 and output one among corresponding output signals Oa-On, latch circuits 13, inverters 14, gate circuits G1 and G2, and resistance R1 and R2, and they have pull-up/pull-down circuits 10 which pull-up or pull- down the input terminals 11 by program signals P. An internal circuit 2 is controlled by the program, outputs the program signals P, inputs the output signals Oa-On from the input terminals 1a-1n and controls the processing of the signals. Consequently, the program can optionally decide whether to pull up or pull down the input terminals 11.</p> |
