An integrated semiconductor device including: a first semiconductor device having a clock generation section, first data storage sections storing input data as transfer data, data output terminals provided, one for each of the first data storage sections, and a clock output terminal adapted to output a transfer clock; and a second semiconductor device having data input terminals which receive the transfer data, a clock input terminal adapted to receive the transfer clock, second data storage sections associated with the data input terminals respectively to store input data, and selection sections associated with the second data storage sections respectively to select either the transfer data or data shifted and output to the associated second data storage section in a first series circuit which is formed by connecting the second data storage sections in series, the selection sections supplying the selected data to the associated second data storage section.