| US 7,456,657 B2 | ||
| Common input/output terminal control circuit | ||
| Sadaharu Fukutoyama, Yokohama (Japan); Masahiro Maeda, Yokohama (Japan); Satoru Kagohashi, Yokohama (Japan); Yuuji Kubo, Yokohama (Japan); Yoshiharu Itou, Yokohama (Japan); and Atsushi Fujita, Kawasaki (Japan) | ||
| Assigned to Fujitsu Limited, Kawasaki (Japan) | ||
| Filed on Jul. 21, 2006, as Appl. No. 11/490,151. | ||
| Claims priority of application No. 2006-086708 (JP), filed on Mar. 27, 2006. | ||
| Prior Publication US 2008/0001631 A1, Jan. 03, 2008 | ||
| Int. Cl. H03K 19/0175 (2006.01) | ||
| U.S. Cl. 326—82 | 11 Claims |
| 1. A common input/output terminal control circuit, comprising:
a first data selection circuit for selecting and outputting a data signal to be transferred to a common input/output terminal
from among a plurality of data signals respectively output from a plurality of circuits;
a direction selection circuit for selecting and outputting a direction control signal of the same circuit as a circuit of
the data signal output from the first data selection circuit from among a plurality of direction control signals respectively
output from the plurality of circuits;
a data holding circuit for holding the data signal output from the first data selection circuit;
a second data selection circuit for selecting and outputting one of the data signal output from the first data selection circuit
and the data signal held by the data holding circuit; and
an output circuit for outputting, to the common input/output terminal, the data signal output from the second data selection
circuit when the direction control signal output from the direction selection circuit indicates an output direction.
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