Data transmitting/receiving apparatus operating in a user-selected one of a line specifying mode and a free-line searching mode

A data transmitting/receiving apparatus comprising:

• transmitting/receiving means for performing a plurality of data transmission operations and data reception operations in parallel via a plurality of data communication lines;
• mode select means for a user to select one of a line specifying mode and a free-line searching mode;
• line determining means for determining a transmission line from among said plurality of data communication lines, said transmission line being then used for performing a data transmission operation by said transmitting/receiving means;
• and wherein:
• said line determining means determines said transmission line as being a line selected by a user from among said plurality of data communication lines when said line specifying mode is selected through said mode selecting means;
• said line determining means searches said plurality of data communication lines for a free one so as to determine said transmission line as being said free one when said free-line searching mode is selected through said mode selecting means;
• and
• order specifying means for the user to specify an order according to which said line determining means searches said plurality of data communication lines for a free one so as to determine said transmission line as being said free one when said free-line searching mode is selected through said mode selecting means.