System for effectively paralleling computer terminal devices

Claim 1

A method of controlling the movement of data between a first driver program and a second driver program, the first and second driver programs included in an operating system for a digital computing system, the method comprising the steps of: generating a third driver program; identifying an original set of vectors used by the first and second driver programs to establish a communication link between each other; generating a new set of vectors to establish communication links between (a) the first driver program and the third driver program and (b) the second device driver program and the third driver program; inserting the new set of vectors in the locations of the original set of vectors; and communicating data between the first and third device driver programs and between the second and third driver programs by way of the communication links established by the insertion of the new set of vectors such that all data passing between the first and second driver programs flows through the third driver program, the flow of data being controlled by the third driver program.

Claim 2

A method of controlling the movement of data between a first driver program and a second driver program, the first and second driver programs included in an operating system for a digital computing system, the method comprising the steps of: generating a third driver program; identifying an original set of vectors used by the first and second driver programs to establish a communication link between each other; generating a new set of vectors to establish communication links between (a) the first driver program and the third driver program and (b) the second device driver program and the third driver program; inserting the new set of vectors in the locations of the original set of vectors; and communicating data between the first and third device driver programs and between the second and third driver programs by way of the communication links established by the insertion of the new set of vectors such that all data passing between the first and second driver programs flows through the third driver program, the flow of data being controlled by the third driver program.

Claim 25

A method of programming a digital computing system so as to connect an auxiliary terminal device in parallel with a selected terminal device, wherein the digital computing system includes a CPU, a memory for storing executable instructions and data, the selected terminal device, an auxiliary terminal device, and an operating system for controlling the flow of data between the CPU and the selected terminal device, and wherein the operating system includes a first device driver associated with the CPU, a second device driver associated with the selected terminal device, and a data communication pathway connecting the first and second device drivers, the method comprising the steps of: generating a driver program adapted for communicating with both the first and second device drivers; allocating a portion of the memory for receiving and storing data passed between the CPU and the selected terminal device; breaking the communication pathway and inserting in the pathway the driver program; reestablishing the communication pathway between the first and second device drivers such that all data flows through the driver program without any apparent interruption at the CPU or at the selected terminal device; and placing the data passed between the CPU and the selected terminal device in a location in the allocated portion of memory whereby the data is accessible by the auxiliary terminal device.

Claim 26

A method of programming a digital computing system so as to connect an auxiliary terminal device in parallel with a selected terminal device, wherein the digital computing system includes a CPU, a memory for storing executable instructions and data, the selected terminal device, an auxiliary terminal device, and an operating system for controlling the flow of data between the CPU and the selected terminal device, and wherein the operating system includes a first device driver associated with the CPU, a second device driver associated with the selected terminal device, and a data communication pathway connecting the first and second device drivers, the method comprising the steps of: generating a driver program adapted for communicating with both the first and second device drivers; allocating a portion of the memory for receiving and storing data passed between the CPU and the selected terminal device; breaking the communication pathway and inserting in the pathway the driver program; reestablishing the communication pathway between the first and second device drivers such that all data flows through the driver program without any apparent interruption at the CPU or at the selected terminal device; and placing the data passed between the CPU and the selected terminal device in a location in the allocated portion of memory whereby the data is accessible by the auxiliary terminal device.

Claim 43

A method of programming a digital computing system including at least one terminal device, an auxiliary terminal device, an operating system having a terminal independent device driver program and at least one terminal dependent device driver program associated with each terminal device, the terminal independent device driver program and the terminal dependent device driver program having a communication link established between each other by way of an original set of vectors, the method comprising the steps of: generating a user driver program structured to (a) emulate the terminal dependent device driver program when communicating with the terminal independent device driver program and to (b) emulate the terminal independent device driver program when communicating with the terminal dependent device driver program; allocating a portion of memory to store the original set of vectors and to store data passing between the terminal independent device driver program and the terminal dependent device driver programs; generating a new set of vectors to establish a communication link between (a) the terminal independent device driver program and the user driver program and (b) the terminal dependent device driver program and the user driver program; establishing a communication link between the user driver program and the terminal independent device driver program and the terminal dependent device driver program by moving the new set of vectors into the location of the original set of vectors such that all data passing between the terminal independent device driver and the terminal dependent device driver flows through, and the flow may be controlled by, the user driver program; and moving the data passing through the user driver program to a location where it may be monitored by an auxiliary terminal device.

Claim 44

A method of programming a digital computing system including at least one terminal device, an auxiliary terminal device, an operating system having a terminal independent device driver program and at least one terminal dependent device driver program associated with each terminal device, the terminal independent device driver program and the terminal dependent device driver program having a communication link established between each other by way of an original set of vectors, the method comprising the steps of: generating a user driver program structured to (a) emulate the terminal dependent device driver program when communicating with the terminal independent device driver program and to (b) emulate the terminal independent device driver program when communicating with the terminal dependent device driver program; allocating a portion of memory to store the original set of vectors and to store data passing between the terminal independent device driver program and the terminal dependent device driver programs; generating a new set of vectors to establish a communication link between (a) the terminal independent device driver program and the user driver program and (b) the terminal dependent device driver program and the user driver program; establishing a communication link between the user driver program and the terminal independent device driver program and the terminal dependent device driver program by moving the new set of vectors into the location of the original set of vectors such that all data passing between the terminal independent device driver and the terminal dependent device driver flows through, and the flow may be controlled by, the user driver program; and moving the data passing through the user driver program to a location where it may be monitored by an auxiliary terminal device.

Claim 53

A method for effectively paralleling an auxiliary terminal device with a selected terminal device, the auxiliary terminal device and the selected terminal device both connected to a digital computer, the digital computer including a CPU, an operating system, a terminal independent device driver, a plurality of terminal dependent device drivers, and a memory, the method comprising the steps of: allocating a user controlling device data structure in the memory; generating a user controlling driver program comprising the steps of: calling a subroutine to return the address of a unit control block associated with a first terminal dependent device driver which is associated with the selected terminal; allocating sufficient space in the memory to hold a first port vector table associated with the first terminal dependent device driver; copying the first port vector table to the allocated portion of memory to create a second port vector table; storing the address of the first port vector table in a unit control block contained in the user controlling device; changing the second port vector table pointers which point to (a) a start terminal output routine and (b) a start direct memory access output routine to point to their corresponding subroutines contained in the user controlling driver program; adding the address of the unit control block associated with the first terminal dependent device driver and adding the address of the unit control block contained in the user controlling device to a list of monitored devices; allocating a second block of memory for use as input and output buffers and to store the address of the input and output buffers in the unit control block contained in the user controlling device; disabling interrupts from the selected terminal; changing the pointers contained in the unit control block associated with the first terminal dependent device driver to point to the second port vector table; copying the address of a get data routine, which retrieves data from the terminal independent device driver and makes that data available to the terminal dependent device driver, from the unit control block assciated with the first terminal dependent device driver to the unit control block contained in the user controlling device; copying the address of a put data routine, which moves data from the terminal dependent device driver to the terminal independent device driver, from the unit control block associated with the first terminal dependent device driver to the unit control block contained in the user controlling device; modifying two pointers in the unit control block associated with the first terminal dependent device driver such that the two pointers point to the get data routine and the put data routine associated with the unit control block contained in the user controlling device; and enabling interrupts from the selected terminal.

Claim 54

A method for effectively paralleling an auxiliary terminal device with a selected terminal device, the auxiliary terminal device and the selected terminal device both connected to a digital computer, the digital computer including a CPU, an operating system, a terminal independent device driver, a plurality of terminal dependent device drivers, and a memory, the method comprising the steps of: allocating a user controlling device data structure in the memory; generating a user controlling driver program comprising the steps of: calling a subroutine to return the address of a unit control block associated with a first terminal dependent device driver which is associated with the selected terminal; allocating sufficient space in the memory to hold a first port vector table associated with the first terminal dependent device driver; copying the first port vector table to the allocated portion of memory to create a second port vector table; storing the address of the first port vector table in a unit control block contained in the user controlling device; changing the second port vector table pointers which point to (a) a start terminal output routine and (b) a start direct memory access output routine to point to their corresponding subroutines contained in the user controlling driver program; adding the address of the unit control block associated with the first terminal dependent device driver and adding the address of the unit control block contained in the user controlling device to a list of monitored devices; allocating a second block of memory for use as input and output buffers and to store the address of the input and output buffers in the unit control block contained in the user controlling device; disabling interrupts from the selected terminal; changing the pointers contained in the unit control block associated with the first terminal dependent device driver to point to the second port vector table; copying the address of a get data routine, which retrieves data from the terminal independent device driver and makes that data available to the terminal dependent device driver, from the unit control block assciated with the first terminal dependent device driver to the unit control block contained in the user controlling device; copying the address of a put data routine, which moves data from the terminal dependent device driver to the terminal independent device driver, from the unit control block associated with the first terminal dependent device driver to the unit control block contained in the user controlling device; modifying two pointers in the unit control block associated with the first terminal dependent device driver such that the two pointers point to the get data routine and the put data routine associated with the unit control block contained in the user controlling device; and enabling interrupts from the selected terminal.