Image forming apparatus controlling input from a first input device or a second input device based on which is connected to the image forming apparatus

An image forming apparatus comprising:

• an image reading portion configured to read an image of an original;
• an image forming portion configured to form an image on a recording medium on the basis of a reading result of said image reading portion;
• an operating panel including a display screen capable of displaying, as software keys, a software numerical key for inputting each of numerical information of 0 to 9, a numeric information input by the software numerical key, and a software execution key for inputting an instruction of a start reading the image of the original by said image reading portion;
• and
• a connecting portion to which a first input device or a second input device is connectable, said first input device including (1) a first numerical key where a plurality of numerical keys for inputting numerical information of 0 to 9, respectively, by being pushed down as hardware keys are disposed in a telephone type arrangement, and (2) a hardware execution key for inputting an instruction of a start reading the image of the original by said image reading portion by being pushed down as the hardware keys, said second input device including (a) a second numerical key where a plurality of numerical keys for inputting numerical information of 0 to 9, respectively, by being pushed down as hardware keys are disposed in an electronic calculator type arrangement, (b) an arithmetic operation key for inputting data on four arithmetic operations by being pushed down as the hardware keys, and (c) Enter key for inputting an instruction of an execution of an arithmetic based on information input by the plurality of numerical keys of said second input device and the four arithmetic operation key by being pushed down as the hardware keys,
• wherein said operating panel displays a numeric information input by said first numerical key of said first input device connected to said connecting portion on said display screen, and said image reading portion starts reading the image of the original based on the instruction input by the execution key of said first input device connected to said connecting portion,
• wherein said operating panel displays a numeric information input by said second numerical key of said second input device connected to said connecting portion on said display screen, and said image reading portion does not start reading the image of the original based on the instruction by the Enter key of said second input device connected to said connecting portion.