Printer control device to enable printing on selected multiple types of recording medium

A printer control device connected to a printer for printing on multiple types of recording medium provided at different printer inputs and having medium transport means for independently transferring each of said multiple types of recording medium at said printer inputs through said printer, and connected to a host computer for controlling the operation of the printer, comprising:

• an interface having a plurality of signal lines connected to communicate with the host computer;
• a recording medium detector at each printer input providing an output indicative of a status of recording medium at said respective printer inputs;
• selection means connected to receive control commands from the host computer for selecting only one or more of specified recording medium detectors from among available of said recording medium detectors in response to host computer commands indicative of said specified recording medium and to provide to said host computer with said status relative to only said specified recording medium;
• said selection means for receiving and responding to a first command to select said specified recording medium detectors for output of status information through said interface to said host computer and respond to a second, independent, command to select from among said specified recording medium detectors those for which status output is used to interrupt printing.

A method for controlling a printer for printing on at least two types of recording medium in response to commands and data received from a host computer over an interface, comprising the steps of:

• providing a recording medium detector for each of the types of recording medium to indicate a status of respective recording medium being either present or absent in the printer,
• selecting one or more of said recording medium detectors via a first command from the host computer constituting a first detector group;
• monitoring the outputs of said first detector group to determine a presence or absence of recording medium via its associated detector;
• disabling initiation of a printing operation by the printer if monitoring indicates an absence of recording medium via said first detector group outputs;
• enabling initiation of a printing operation by the printer if monitoring indicates a presence of recording medium via said first detector group outputs;
• selecting one or more of said recording medium detectors via a second command from the host computer constituting a second detector group;
• monitoring the outputs of said second detector group to determine an absence of recording medium via its associated detector;
• and
• interrupting a printing operation in progress by the printer if monitoring indicates an absence of recording medium via said second detector group outputs.

A printer control device for a printer for printing on at least two types of recording medium at different printer inputs in response to commands received from a host computer, comprising:

• an interface for receiving control commands from the host computer;
• medium transport means for independently transporting each of said at least two types of recording media from said printer inputs through said printer;
• advancement storage means connected to said medium transport means for storing line advancement values corresponding to each of said types of recording medium, wherein said advancement values represent an amount by which each type of recording medium is to be transported by said transport means when said medium is advanced in the printer for a printing operation;
• and
• a command execution controller connected to said interface, medium transfer means, and advancement storage means for receiving and decoding said control commands, for retrieving an advancement value corresponding to a selected recording medium type, and for activating said transport means for advancement of said selected recording medium type as specified by said host computer via said retrieved advancement value.

A method for controlling a printer for printing on at least two types of recording medium in response to commands received from a host computer and including medium transport means to move a selected recording medium in the printer for a printing operation, comprising the steps of:

• receiving and interpreting control commands from said host computer relating to recording medium type and its line advancement value for recording medium advancement by said medium transport means through the printer a predetermined incremental medium advancement spacing;
• selecting one of said types of recording medium to be used in a printing operation based upon the interpreted control commands;
• storing the advancement value based upon the interpreted control commands in advancement storage means relative to the selected one of said types of recording medium,
• retrieving the line advancement value from the advancement storage means corresponding to the selected one of said types of recording medium;
• and
• controlling the advancement of the selected one of said types of recording medium via the medium transport means in the printer for printing on successive lines of the selected recording medium at the predetermined medium advancement spacing.

A method of operating a printer through a host computer wherein the printer is provided with two or more types of printing medium sources provided at different printer inputs for different printing applications comprising the printing of lines of information and a detector associated with each of said different printer inputs for determining if its respective printing medium source status is present or empty and indicating that status through a single status line to the host computer, comprising the steps of:

• selecting one or more detectors whose output is to be checked for status,
• setting a first detector flag for each selected detector to be observed by the host computer,
• setting a second detector flag for each selected detector where a printing operation is to be interrupted if a printing medium source status is indicative of empty,
• periodically checking the printing medium source status for each detector whose first flag is set,
• observing the output of the checked detector whose first flag is set as to the printing medium source status,
• combining the status outputs for transfer via the single status line to the host computer indicative of the printing medium source status of each detector whose first flag is set, and
• interrupting the printing operation for each detector whose second flag is set if its printing medium source status is indicative of empty.

A method of operating a printer through a host computer wherein the printer is provided with two or more types of printing medium sources provided at different printer inputs for different printing applications and with printing medium transport means to transport a recording medium from a corresponding printing medium source through a path in the printer past a print head, comprising the steps of:

• receiving control commands from the host computer indicative of print line advancement values,
• storing in an advance memory the print line advancement value for each printing medium source type,
• selecting a printing medium source type in preparation of a printing operation on a selected medium,
• retrieving a print line advancement value from the advance memory for the selected printing medium source type, and
• operating the printer printing medium transport means to transport the selected recording medium past the print head at a line advance rate commensurate with the retrieved print line advancement value.