Abstract: First an operating system, along with the host-based printing system, are initialized. The queue processor waits for the host-based printing system to issue a job open command. While waiting for a job open command, other applications may acquire and use the parallel port. Upon receiving a job open command, the queue processor informs the engine monitor to acquire the parallel port resource from the operating system. After the print job is done or canceled, the queue processor checks whether there are any additional print jobs than have been sent since the parallel port was acquired. After all print jobs are completed or canceled, the queue processor informs the engine monitor to release the parallel port resource to the operating system. Once the engine monitor has released the parallel port resource, the queue processor again waits for the next job open command.

Abstract: The preferred embodiment of the present invention provides a method for a host computer to improve control over the printer memory buffering in conjunction with commencing print engine motion. By requiring both data present in the printer and a "begin engine motion" notification from the host computer, print engine commencement is controlled completely by the host computer. To help the host better control the buffer, the host establishes a "memory full" threshold limit. This threshold is then transferred to the printer and is used by the printer to determine when to return a "threshold exceeded" notification to the host. After the data has moved from the printer memory buffer and onto the printed page, memory is again considered free. Once the unused portion of printer memory is larger than the memory full threshold value, the threshold exceeded status is reset.

Abstract: A system and method controls logical channel use when ECP negotiation is made between a host computer and a dual mode printer. Namely, specifically defined logical channel functionality is provided for the dual mode printer supporting, for example, Sleek ECP and PCL ECP communications. The method comprises (a) the host computer negotiating with the printer into a first communication mode other than ECP mode, in the event that the computing system is to subsequently enter into Sleek ECP mode; (b) setting a placeholder in a memory of the printer, the placeholder indicating that subsequent negotiation into ECP mode requires logical channel use; (c) terminating the first communication mode; (d) negotiating into ECP mode; (e) reading the placeholder to determine if it is set; and, (f) activating logical channels for use in the event the placeholder is set.

Abstract: A host computer includes a processor, a first memory for storing a bit map representation of an image to be printed, and a second memory for storing a control language representation of an image to be printed. The host computer further includes a printer driver for enabling dispatch of the bit map representation to a connected printer. The printer includes a print engine, a printer processor and control memory for storing bit map control code which controls the printer processor to render the print engine able to print an image defined by a bit map representation. The control memory further includes control language code for controlling the printer's processor to render the print engine able to print an image defined by a control language representation. Within the host computer is an interface module, controlled by the host printer driver, for interrogating status information from the printer.

Abstract: Reducing I/O port activity allows a period of inactivity to trigger the power save mode in computers. The user declares the period of inactivity. The printing system retrieves the period and relaxes the port activity by gradually lengthening the period between port accesses until the user designated value is reached. This relaxation happens under two circumstances; when the printer is idle and during communication errors. The period between port accesses is reinitialized to the normal value when a print job starts. Additionally, when the computer is awoken from the power save mode, either directly or indirectly, the port access period is shortened to its normal value. The printing system immediately starts to relax the frequency of port accesses as described above.

Abstract: The present invention is a method for recovering a page that fails to print in a host based printing environment. In order to accomplish the present invention, first, if printer supports printing at a slower speed, the printer is slowed down. Next, if the printer cannot be slowed down or a page still faults while printing at the slowest speed, the resolution of the page is determined. If the resolution is a first resolution then the printer is checked to see if it has enough memory. Assuming there is enough memory, it is used to pre-buffer the page prior to starting the printer. If the resolution is a second resolution then first, if the printer has enough memory, try the pre-buffering method. If the page still faults then changing the page's resolution to the first resolution.