Printer driver and POS system

1. A terminal comprising a printer driver configured to:

generate first print data based on application data from a specific application, the first print data configured to cause a printer connected to a communication port to print;

occupy the communication port when the application data is supplied, and release the communication port when a previously set time passes;

transmit the first print data to the printer using the communication port;

communicate with a second printer driver, and transmit the first print data to the second printer driver;

receive, from the second printer driver, second print data based on the first print data, the second print data configured to cause the printer to print; and

transmit the second print data to the printer.

2. The terminal described in claim 1 , wherein the printer driver is further configured to:

release the communication port when the previously set time has passed since a reference time,

wherein the reference time is a time at which the transmission of the first print data ended.

3. A terminal comprising a printer driver configured to:

generate print data, based on application data from a specific application, that causes a printer connected to a communication port to print;

occupy the communication port when the application data is supplied, and release the communication port when a previously set time passes;

send the print data through the communication port to the printer when the print data is generated;

communicate with a second printer driver configured to control the printer, receive from the second printer driver second print data that causes the printer to print, and send the second print data to the printer;

send an error indication to the second printer driver if the printer driver is occupying the communication port when the second print data is sent from the second printer driver; and

send the second print data to the printer if the printer driver is not occupying the communication port when the second print data is sent from the second printer driver.

4. A terminal comprising a printer driver configured to:

generate print data, based on application data from a specific application, that causes a printer connected to a communication port to print;

occupy the communication port when the application data is supplied, and release the communication port when a previously set time passes;

send the print data through the communication port to the printer when the print data is generated;

communicate with a second printer driver configured to control the printer, receive from the second printer driver second print data that causes the printer to print, and send the second print data to the printer; and

hold the second print data received from the second printer driver, and send the second print data to the printer after releasing the communication port.

5. A terminal comprising a printer driver configured to:

generate print data, based on application data from a specific application, that causes a printer connected to a communication port to print, the application data comprising an operating command for operating a device connected to the printer and the communication port;

generate a control command corresponding to the operating command when the operating command is supplied;

occupy the communication port when the application data is supplied, and release the communication port when a previously set time passes;

send the print data through the communication port to the printer when the print data is generated; and

send the control command to the device through the communication port when the control command is generated, and continue to occupy the communication port until an end message indicating that an operation corresponding to the control command has ended is received from the device.

6. A point of sale system comprising:

a point of sale terminal configured to execute:

a first printer driver configured to:

generate print data, based on application data from a specific application, that causes a printer connected to a communication port of a computer to print;

occupy the communication port when the application data is supplied, and release the communication port when a previously set time passes;

send the print data through the communication port to the printer when the print data is generated; and

communicate with a second printer driver configured to control the printer, receive from the second printer driver second print data that causes the printer to print, and send the second print data to the printer; and

the specific application; and

a server communicatively connected to the point of sale terminal, and configured to execute the second printer driver and a second application configured to supply second application data to the second printer driver,

wherein the second printer driver is configured to generate, based on the second application data, the second print data that causes the printer to print, and is configured to send the second print data to the first printer driver when the second print data is generated,

the specific application is a point of sale application configured to generate the application data for printing a receipt, and

the second application is a coupon printing application configured to generate the second application data for printing a coupon.

7. The point of sale system described in claim 6 , wherein:

the second printer driver is configured such that when an error indicating the communication port is occupied is sent from the first printer driver, the second printer driver repeats the transmission operation sending the second print data to the first printer driver until an error is not returned from the first printer driver.

8. A method for controlling a terminal comprising a printer driver, the method comprising:

generating print data, based on application data from a specific application, that causes a printer connected to a communication port to print;

occupying the communication port when the application data is supplied, and releasing the communication port when a previously set time passes;

transmitting the print data to the printer using the communication port;

communicating with a second printer driver, and transmitting the print data to the second printer driver; and

receiving second print data, based on the print data from the second printer driver, that causes the printer to print, and sending the second print data to the printer.

9. The method for controlling a terminal described in claim 8 , further comprising:

sending an error indication to the second printer driver responsive to determining that the printer driver is occupying the communication port when the second print data is sent from the second printer driver; or

sending the second print data to the printer responsive to determining that the printer driver is not occupying the communication port when the second print data is sent from the second printer driver.