Facsimile, method of controlling the same and image forming apparatus having facsimile function

A method of controlling a facsimile, the facsimile comprising a line terminal provided for connection with a line cord and connected with a first signal line, an external device terminal provided for connection with an external device and connected with a second signal line, and a switching unit to perform switching between the first signal line and the second signal line, the method comprising:

• determining a connection state between the line terminal and the line cord and a connection state between the external device terminal and the external device;
• and
• controlling, when the external device and the line cord are reversely connected respectively to the line terminal and the external device terminal, the switching unit to interchange a path of the first signal line and a path of the second signal line to enable use of the external device connected to the line terminal and communication through the line cord connected to the external device terminal,
• wherein a first switch having a first contact connected to the first signal line, the first signal line extending from the line terminal, and a second contact connected to the second signal line, the second signal line extending from the external device terminal, the first switch performing switching between the first contact and the second contact, and
• a second switch having a third contact connected to the first signal line extending from the line terminal, and a fourth contact connected to the second signal line extending from the external device terminal, the second switch performing switching between the third contact thereof and the fourth contact thereof,
• wherein the first switch and the second switch share a common line with each other.

An image forming apparatus with a facsimile function, comprising:

• a line terminal provided for connection with a line cord and connected with a first signal line;
• an external device terminal provided for connection with an external device and connected with a second signal line;
• a switching unit to perform switching between the first signal line and the second signal line;
• and
• a controller to determine a connection state between the line terminal and the line cord and a connection state between the external device terminal and the external device, and to, when the external device and the line cord are reversely connected respectively to the line terminal and the external device terminal, control the switching unit to interchange a path of the first signal line and a path of the second signal line to enable use of the external device connected to the line terminal and communication through the line cord connected to the external device terminal,
• wherein the switching unit comprises:
• a first switch having a first contact connected to the first signal line, the first signal line extending from the line terminal, and a second contact connected to the second signal line, the second signal line extending from the external device terminal, the first switch performing switching between the first contact and the second contact, and
• a second switch having a third contact connected to the first signal line extending from the line terminal, and a fourth contact connected to the second signal line extending from the external device terminal, the second switch performing switching between the third contact thereof and the fourth contact thereof,
• wherein the first switch and the second switch share a common line with each other.

An apparatus, comprising:

• a first terminal provided for connection with a first device and connected with a first signal line;
• a second terminal provided for connection with a second device and connected with a second signal line;
• a switching unit to perform switching between the first signal line and the second signal line;
• and
• a controller to determine a connection state between the first terminal and the first device and a connection state between the second terminal and the second device, and to, when the second device and the first device are reversely connected respectively to the first terminal and the second terminal, control the switching unit to interchange a path of the first signal line and a path of the second signal line to enable use of the second device connected to the first terminal and communication through the first device connected to the second terminal,
• wherein the switching unit comprises:
• a first switch having a first contact connected to the first signal line, the first signal line extending from the first terminal, and a second contact connected to the second signal line, the second signal line extending from the second terminal, the first switch performing switching between the first contact and the second contact, and
• a second switch having a third contact connected to the first signal line extending from the first terminal, and a fourth contact connected to the second signal line extending from the second terminal, the second switch performing switching between the third contact thereof and the fourth contact thereof,
• wherein the first switch and the second switch share a common line with each other.

A method of controlling a connection, the method comprising:

• determining a connection state between a first terminal and a first device and a connection state between a second terminal and a second device;
• and
• controlling, when the second device and the first device are reversely connected respectively to the first terminal and the second terminal, a switching unit to interchange a path of the first signal line and a path of the second signal line to enable use of the second device connected to the first terminal and communication through the first device connected to the second terminal,
• wherein the switching unit comprises:
• a first switch having a first contact connected to the first signal line, the first signal line extending from the first terminal, and a second contact connected to the second signal line, the second signal line extending from the second terminal, the first switch performing switching between the first contact and the second contact, and
• a second switch having a third contact connected to the first signal line extending from the first terminal, and a fourth contact connected to the second signal line extending from the second terminal, the second switch performing switching between the third contact thereof and the fourth contact thereof,
• wherein the first switch and the second switch share a common line with each other.