Abstract: The technique of the present invention intermediates between an arbitrary client and an arbitrary printer connecting with a network to actualize practical printing works.

Abstract: A constructed system includes multiple clients, a server like a print portal, and multiple printers connecting with a network. A client transmits a printing requirement, which specifies a content of interest to be printed and a printer as an output resource, to the print portal. The print portal transmits the specified content of interest to the specified printer, which then carries out the actual printing operation. A security system interposed between the print portal and the printer in principle refuses transmission of data from the print portal, but allows transmission of the printing requirement from the client when direct communication between the printer and the client is established by means of infrared ray or feeble radio wave. This arrangement ensures the sufficient level of security, while enhancing utility of printing via the network.

Abstract: A constructed system includes multiple clients, a server like a print portal, and multiple printers connecting with a network. A client transmits a printing requirement, which specifies a content of interest to be printed, to the print portal through communication C1. The printing requirement is kept in the print portal in such a state that enables specification by address information IPMP of the client. Direct communication C2 is established between a printer and the client by means of feeble radio wave or infrared, and the print portal fetches address information IPMP of the client and identification information of the printer through the direct communication C2. The print portal compares the two pieces of address information received on the two different communication lines with each other and specifies the printer identified by the identification information as an output resource.

Abstract: The technique of the present invention intermediates between an arbitrary client and an arbitrary printer connecting with a network to actualize practical printing works.

Abstract: The present invention provides a spooler that adequately manages and controls print jobs, which require establishment of mutual communication, with relieved loading. In the arrangement of the present invention, a buffer is provided corresponding to each printer PRT connected to a network LAN to successively spool print jobs transferred from clients. In the case of a conventional print job, a print queue and whole print data are spooled in the buffer. In the case of an interactive print job that requires mutual communication between the client and the printer, only the print queue is stored in the buffer, while a wait signal is output to the client to wait for transmission of the print data of the print job. In order to carry out the interactive print job, printing is executed via a bypass that establishes the mutual communication not via the buffer but directly between a print job execution unit and the client.

Abstract: An emulator that emulates the operation of a target machine on an execution machine is disclosed. The execution module prepared for each function of the target machine is called via a dispatcher from a kernel. A calling address is registered in a dispatcher table by the execution module when each execution module is loaded. Inputs from a keyboard causes a hardware interrupt resulting in the calling of a keyboard emulator. After a converted key code is stored in a buffer, an interrupt controller emulator is called by intermodule communication. The interrupt controller emulator requests a virtual interrupt for the kernel. The keyboard emulator is called again and the key code stored in the buffer is transmitted to the application program.

Abstract: What is disclosed is an emulator that emulates on an execution machine the operation of a target machine. The emulator emulates routines that are called via a jump table such as the BIOS. Control is transferred to an emulation module not by directly trapping the procedure to call the BIOS but by placing a privileged instruction (a halt instruction, for example) in the area called and by causing a trap through the execution of the privileged instruction. An identifier is placed after the halt instruction and a needed BIOS emulation module is called by a dispatcher using this identifier. Therefore, normal operation can be obtained even if there is a resident program which rewrites the jump table.

Abstract: An apparatus for controlling an image display device such as the CRT includes a dual port memory having a first memory and a second memory. Data may be written into a first memory and read from the first memory at any time. Data is sequentially read from the second memory to provide information for the display. Data is manipulated during a data transfer cycle, a dynamic memory refresh cycle, a memory write cycle and a memory read cycle. Data is transmitted between the first memory and second memory during a data transfer cycle. A cycle reconciliation circuit prioritizes the manner in which the cycles occur giving top priority to the data transfer cycle.