Integrated computer and printer system and method for managing power source therefor

A method for managing a power source for an integrated computer and printer system having a monolithic, unitary structure containing therein a computer unit, a display unit, and a printer unit, said method comprising the steps of:

• turning on the power source of the display unit and the printer unit when the operator turns on the main power switch;
• determining whether the computer unit is in a power saving mode;
• transmitting a power saving control signal to the printer unit to set the printer unit in the power saving mode, when the computer unit is in the power saving mode;
• determining whether the computer unit is awaken under instruction of the operator while the computer unit is in the power saving mode;
• determining whether the print command is input by the operator after the computer unit is awaken;
• and
• transmitting a wake-up control signal to the printer unit to wake up the printer unit for beginning the printing operation.

A method for managing a power source for an integrated computer and printer system having a monolithic, unitary structure containing therein a computer unit, a display unit, and a printer unit, said method comprising the steps of:

• initializing the printer unit when an operator turns on the main power switch;
• determining whether a print command is received from the computer unit when the operator presses the print command;
• waking up the printer unit to perform printing operation, when the print command is received from the computer unit;
• determining whether a power saving control signal is received from the computer unit, when the print command is not received from the computer unit;
• setting the printer unit in a power saving mode, when the power saving control signal is received from the computer unit;
• determining whether a wake-up control signal is received from the computer unit for waking up the printer unit;
• waking up the printer unit to perform printing operation, when the wake-up control signal is received from the computer unit;
• and
• alternatively, setting the printer unit in a power source management mode in which, when the operator does not input the print command for a predetermined time period, the printer unit automatically sets to the power saving mode and awaits for the next print command.

In an integrated computer and printer system having a computer unit and an internal printer unit constructed in a monolithic, unitary housing, a method for selecting one of the internal printer unit of said integrated computer and printer system and an external printer unit connected to said integrated computer and printer system through an external interface port, comprising the steps of:

• determining whether the external printer unit is connected to the external interface port of said integrated computer and printer system;
• setting the internal printer unit constructed in said integrated computer and printer system as a current printer unit for printing a document, when the external printer unit is not connected to the external interface port of said integrated computer and printer system;
• and
• setting one of the internal printer unit and the external printer unit as the current printer unit for performing said printing of a document, when the external printer unit is connected to the external interface port of said integrated computer and printer system.