System for supporting an ERASE INPUT key with input suppression in a system for optimizing data transmission associated with addressable-buffer devices

• US 4,837,679 A
• Filed: 12/31/1986
• Issued: 06/06/1989
• Est. Priority Date: 12/31/1986
• Status: Expired due to Term

• Current Assignee: BMC Software Incorporated (KKR & Co., Inc.)
• Original Assignee: BMC Software Incorporated (KKR & Co., Inc.)
• Inventors: Wiles, Philip V. Jr., Harper, Thomas A., Harper, Carol R.
• Primary Examiner(s): Shaw, Gareth D.
• Assistant Examiner(s): JAFFE, MICHAEL
• Application Number:
  US06/948,150
• Time in Patent Office: 888 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 364/514
• US Class Current: 710/54
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 3/1415 with means for detecting differences between the image stored in the host and the images displayed on the displays

Abstract

ERASE INPUT support is provided for the optimizer system disclosed in commonly-assigned co-pending application Ser. No. 827,767, now U.S. Pat. No. 4,750,137, by altering the programming of the optimizer system so that the only MDT flags turned off in the optimized outgoing data stream are those associated with protected pre-modified fields. The programming is further altered so that when an incoming data stream is received by the optimizer system, all unprotected fields in the present-state image are preprocessed prior to being updated from the incoming data stream to reflect the information available to the optimizer system as to whether the ERASE INPUT key has been pressed.

Claims

1. A method for optimizing a signal exchange,

said signal exchange including one or more outgoing transmissions of outgoing signals having information contents and generated by a host unit to be received for processing by a peripheral unit,

said signal exchange further including one or more incoming transmissions of incoming signals having information contents and generated by the peripheral unit to be received for processing by the host unit,

said peripheral device having an addressable peripheral unit buffer modifiable at the peripheral unit in response to the information contents of an outgoing signal,

the peripheral unit buffer having information contents that are logically dividable into one or more fields,

each said field having a field attribute byte for representation of field attributes,

one said field attribute being a modified data tag (MDT) signifying a premodified field and capable of selectively having a set state or an unset state,

another field attribute being a protected-field attribute representing a protected field,

said method comprising the steps, executed by a machine, of:

creating a buffer contents map in a storage device, said buffer contents map representing information available at the machine about the informational contents of said peripheral unit buffer;

for each outgoing signal that would cause a modification of the informational contents of the peripheral unit buffer,

blocking the outgoing signal from being processed by the peripheral unit,

updating said buffer contents map to reflect the informational content of said outgoing signal, and

generating and transmitting to the peripheral unit an input-suppressed signal,

any MDT for any protected field in the outgoing signal being in said unset state in said inputsuppressed signal;

for each incoming signal subsequent to a previous said outgoing signal,

blocking the incoming signal from being processed by the host unit,

updating said buffer contents map to reflect the informational content of said incoming signal,

if no fields in the outgoing signal were premodified fields, filling all unprotected fields in the buffer contents map with an in-doubt character,

if the incoming signal includes fields corresponding to all premodified fields in the outgoing signal, filling all unprotected fields in the buffer contents map with an in-doubt character,

otherwise, if the incoming signal includes fields corresponding to less than all premodified fields in the outgoing signal, filling all unprotected fields in the buffer contents map with nulls, and

generating and transmitting an augmented incoming signal to the host unit,

said augmented incoming signal including the informational content of the buffer contents map corresponding to the fields in the peripheral unit buffer, if any, associated with any premodified fields in the previous outgoing signal.

2. A method for optimizing an exchange of one or more signals,

said exchange including one or more transmissions of outgoing signals generated by a host unit to be received for processing by a peripheral unit,

said exchange further including one or more transmissions of incoming signals generated by the peripheral unit to be received for processing by the host unit,

each said signal having encoded within it, one after another, one or more members of a set of protocol symbols defined by a protocol for use in representing data,

each said signal being organized in accordance with rules defined by said protocol for classification of protocol symbols into a first class of meaning or one or more other classes of meaning,

said classification of a given protocol symbol being affected (a) by whether said

given protocol symbol is a member of a group of zero or more special protocol symbols, and (b) if not, by a positional relationship within the signal, if any, between said given protocol symbol and zero or more of such special protocol symbols;

said peripheral unit having an addressable peripheral unit buffer modifiable at the peripheral unit in response to addressing commands encoded into an outgoing signal and having information contents that are logically dividable into one or more fields,

each said field having a field attribute byte for representation of field attributes,

one said field attribute being a modified data tag (MDT) signifying a premodified field and capable of selectively having a set state or an unset state,

another field attribute being a protected-field attribute representing a protected field,

said peripheral unit buffer having existing information contents corresponding to one or more buffer-contents symbols that are members of said set of protocol symbols,

said existing information contents of the peripheral unit buffer being represented in a present-state map stored in a storage device,

each buffer-contents symbol within said first class of meaning being represented within said presentstate map by one or more translated symbols which are not members of said set of protocol symbols,

said method comprising the steps, executed by a machine, of;

for each outgoing signal that would cause the peripheral unit to modify the information contents of the peripheral unit buffer resulting in new information contents for the peripheral unit buffer,

blocking the outgoing signal from being processed by the peripheral device,

generating an updated-state map in a storage device, utilizing the present-state map and the outgoing signal as inputs,

said updated-state map representing said new information contents of the peripheral unit buffer,

each buffer-contents symbol within said first class of meaning being represented within said updatedstate map by one or more translated symbols which are not members of said set of protocol symbols;

generating and transmitting to the peripheral unit an input-suppressed signal,

each symbol in said input-suppressed signal that is classified within said first class of meaning being encoded as one or more symbols which are members of said set of protocol symbols,

said input-suppressed signal including an MDT in said unset state for any protected field in the outgoing signal;

for each incoming signal subsequent to a previous outgoing signal,

blocking the incoming signal from being processed by the host unit,

utilizing the present-state map and the informational content of said incoming signal to generate a new present-state map representing the new information contents of the peripheral unit buffer,

if no fields in said previous outgoing signal were premodified fields, all unprotected fields in the new present-state map being filled with an in-doubt character,

else if the incoming signal includes fields corresponding to all the premodified fields in the outgoing signal, all unprotected fields in the new present-state map being filled with an in-doubt character,

else if the incoming signal includes fields corresponding to less than all premodified fields in the outgoing signal, all unprotected fields in the new present-state map being filled with nulls,

generating and transmitting an augmented incoming signal to the host unit,

each symbol in said augmenting incoming signal that is classified within said first class of meaning being encoded as one or more symbols which are members of said set of protocol symbols,

said augmented incoming signal including the informational content of the new present-state map corresponding to any premodified fields in the previous outgoing signal.