Methods and apparatuses to identify devices

Abstract

An apparatus and method to identify devices including a first set of commands to identify devices in a first state and a second set of commands to identify devices in a second state, wherein devices identified in the first state are placed in the second state and devices identified in the second state are placed in the first state.

1 - 37 . (canceled) 
     
     
         38 . A method for identifying tags, the method comprising:
 issuing a first set of commands in a first inventory process to identify a first plurality of tags in a first state, and to place the first plurality of tags which are identified in the first state in a second state; and   issuing a second set of commands in a second inventory process to identify a second plurality tags in the second state and to place the second plurality of tags which are identified in the second state in the first state, wherein the first state prevents the identified tags from responding to the second set of commands and enables the identified tags to respond to the first set of commands and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         39 . The method of  claim 38  wherein:
 the first set of commands and the second set of commands are symmetrical sets of commands and the first state and the second state are symmetrical states. 
 
     
     
         40 . The method of  claim 38 , further comprising:
 receiving identification information from at least one tag in response to one of the first set of commands or the second set of commands.   
     
     
         41 . The method of  claim 38 , further comprising:
 issuing a third command in the first set of commands to address tags in the first state, wherein the third command in the first set of commands causes addressed tags to be placed in a third group of tags in a third state; and   issuing a fourth command in the second set of commands to address tags in the second state, wherein the fourth command in the second set of commands causes addressed tags to be placed in the third group of tags in the third state.   
     
     
         42 . The method of  claim 38 , further comprising:
 sending a first command of the first set of commands to interrogate those of the first plurality of tags that are in the first state;   classifying those of the first plurality of tags which respond to the first command;   sending one or more subsequent commands of the first set of commands to interrogate at least some of those of the first plurality of tags which responded to the first command;   sub-classifying those of the first plurality of tags which respond to the one or more subsequent commands of the first set of commands until each sub-class has a single member;   identifying each of those of the first plurality of tags which is the single member of the each one of the sub-classes;   changing the state of the identified tags to the second state.   
     
     
         43 . A method performed in a tag, the method comprising:
 receiving at a tag in a first state, a first set of commands in a first inventory process to identify the tag in the first state, wherein, as a result of being identified, the tag in the first state is placed in a second state;   receiving at the tag in the second state, a second set of commands in a second inventory process to identify the tag in the second state, wherein, as a result of being identified, the tag in the second state is placed in the first state, the first state preventing the identified tags from responding to the second set of commands and enabling the identified tags to respond to the first set of commands, and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         44 . The method of  claim 43 , wherein the first set of commands and the second set of commands are symmetrical sets of commands, and the first state and the second state are symmetrical states. 
     
     
         45 . The method of  claim 43 , further comprising:
 sending identification information in response to one of the first set of commands or the second set of commands.   
     
     
         46 . The method of  claim 43 , further comprising:
 receiving a third command in the first set of commands, wherein the third command in the first set of commands causes the tag in the first state to be placed in a third state in a third group of tags; and   receiving at the tag a fourth command in the second set of commands, wherein the fourth command in the second set of commands causes the tag in the second state to be placed in the third state in the third group of tags.   
     
     
         47 . The method of  claim 43 , further comprising:
 receiving interrogation data, the interrogation data comprising the first set of commands to identify tags in the first state; and the second set of commands to identify tags in the second state;   detecting a portion of the interrogation data representing at least a portion of an identification code;   comparing the portion of the interrogation data to the at least the portion of the identification code imbedded in a memory in the tag;   generating a response code if the portion of the interrogation data matches the at least a portion of the identification code imbedded in the memory in the tag.   
     
     
         48 . A non-transitory machine readable medium containing instructions, which when executed by a data processing system, cause the data processing system to perform operations for identifying tags comprising:
 issuing a first set of commands in a first inventory process to identify a first plurality of tags in a first state, and to place the first plurality of tags which are identified in the first state in a second state; and   issuing a second set of commands in a second inventory process to identify a second plurality tags in the second state and to place the second plurality of tags which are identified in the second state in the first state, wherein the first state prevents the identified tags from responding to the second set of commands and enables the identified tags to respond to the first set of commands and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         49 . The non-transitory machine readable medium of  claim 48 , wherein
 the first set of commands and the second set of commands are symmetrical sets of commands; and the first state and the second state are symmetrical states.   
     
     
         50 . The non-transitory machine readable medium of  claim 48 , further comprising instructions that cause the data processing system to perform operations comprising
 receiving identification information from at least one tag in response to one of the first set of commands or the second set of commands.   
     
     
         51 . The non-transitory machine readable medium of  claim 48 , further comprising instructions that cause the data processing system to perform operations comprising:
 issuing a third command in the first set of commands to address tags in the first state, wherein the third command in the first set of commands causes addressed tags to be placed in a third group of tags in a third state; and   issuing a fourth command in the second set of commands to address tags in the second state, wherein the fourth command in the second set of commands causes addressed tags to be placed in the third group of tags in the third state.   
     
     
         52 . The non-transitory machine readable medium of  claim 48 , further comprising instructions that cause the data processing system to perform operations comprising sending a first command of the first set of commands to interrogate those of the first plurality of tags that are in the first state;
 classifying those of the first plurality of tags which respond to the first command;   sending one or more subsequent commands of the first set of commands to interrogate at least some of those of the first plurality of tags which responded to the first command;   sub-classifying those of the first plurality of tags which respond to the one or more subsequent commands of the first set of commands until each sub-class has a single member;   identifying each of those of the first plurality of tags which is the single member of the each one of the sub-classes;   changing the state of the identified tags to the second state.   
     
     
         53 . A non-transitory machine readable medium containing instructions, which when executed by a data processing system, cause the data processing system to perform operations comprising:
 receiving at a tag in a first state, a first set of commands in a first inventory process to identify the tag in the first state, wherein, as a result of being identified, the tag in the first state is placed in a second state;   receiving at the tag in the second state, a second set of commands in a second inventory process to identify the tag in the second state, wherein, as a result of being identified, the tag in the second state is placed in the first state, the first state preventing the identified tags from responding to the second set of commands and enabling the identified tags to respond to the first set of commands, and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         54 . The non-transitory machine readable medium of  claim 53 , wherein the first set of commands and the second set of commands are symmetrical sets of commands, and the first state and the second state are symmetrical states. 
     
     
         55 . The non-transitory machine readable medium of  claim 53 , further comprising instructions that cause the data processing system to perform operations comprising sending identification information in response to one of the first set of commands or the second set of commands. 
     
     
         56 . The non-transitory machine readable medium of  claim 53 , further comprising instructions that cause the data processing system to perform operations comprising
 receiving at the tag in the first state a third command in the first set of commands, wherein the third command in the first set of commands causes the tag to be placed in a third state in a third group of tags; and   receiving at the tag in the second state a fourth command in the second set of commands, wherein the fourth command in the second set of commands causes the tag to be placed in the third state in the third group of tags.   
     
     
         57 . The non-transitory machine readable medium of  claim 53 , further comprising instructions that cause the data processing system to perform operations comprising
 receiving interrogation data, the interrogation data comprising the first set of commands to identify tags in the first state; and the second set of commands to identify tags in the second state;   detecting a portion of the interrogation data representing at least a portion of an identification code;   comparing the portion of the interrogation data to the at least the portion of the identification code imbedded in a memory in the tag;   generating a response code if the portion of the interrogation data matches the at least a portion of the identification code imbedded in the memory in the tag.   
     
     
         58 . A reader for identifying tags comprising:
 a memory; and   a processor coupled to the memory, wherein the processor is configured to issue a first set of commands in a first inventory process to identify a first plurality of tags in a first state, and to place the first plurality of tags which are identified in the first state in a second state; and   wherein the processor is configured to issue a second set of commands in a second inventory process to identify a second plurality tags in the second state and to place the second plurality of tags which are identified in the second state in the first state, wherein the first state prevents the identified tags from responding to the second set of commands and enables the identified tags to respond to the first set of commands and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         59 . The reader of  claim 58 , wherein the first set of commands and the second set of commands are symmetrical sets of commands; and the first state and the second state are symmetrical states. 
     
     
         60 . The reader of  claim 58 , wherein the processor is further configured to receive identification information from at least one tag in response to one of the first set of commands or the second set of commands. 
     
     
         61 . The reader of  claim 58 , wherein the processor is further configured to issue a third command in the first set of commands to address tags in the first state, wherein the third command in the first set of commands causes addressed tags to be placed in a third group of tags in a third state; and wherein the processor is further configured to issue a fourth command in the second set of commands to address tags in the second state, wherein the fourth command in the second set of commands causes addressed tags to be placed in the third group of tags in the third state. 
     
     
         62 . The reader of  claim 58 , wherein the processor is further configured to send a first command of the first set of commands to interrogate those of the first plurality of tags that are in the first state, wherein the processor is further configured to classify those of the first plurality of tags which respond to the first command, wherein the processor is further configured to send one or more subsequent commands of the first set of commands to interrogate at least some of those of the first plurality of tags which responded to the first command, wherein the processor is further configured to sub-classify those of the first plurality of tags which respond to the one or more subsequent commands of the first set of commands until each sub-class has a single member, wherein the processor is further configured to identify each of those of the first plurality of tags which is the single member of the each one of the sub-classes, wherein the processor is further configured to change the state of the identified tags to the second state. 
     
     
         63 . A tag, comprising:
 a memory; and   a processor coupled to the memory, wherein the processor is configured to receive a first set of commands in a first inventory process to identify the tag in a first state, wherein, as a result of being identified, the tag in the first state is placed in a second state, wherein the processor is configured to receive a second set of commands to identify the tag in the second state, wherein, as a result of being identified, the tag in the second state is placed in the first state, the first state preventing the identified tag from responding to the second set of commands and enabling the identified tags to respond to the first set of commands, and wherein the second inventory process is performed in a same way as the first inventory process.   
     
     
         64 . The tag of  claim 63 , wherein the first set of commands and the second set of commands are symmetrical sets of commands; and the first state and the second state are symmetrical states. 
     
     
         65 . The tag of  claim 63 , wherein the processor is further configured to send the identification information in response to one of the first set of commands or the second set of commands. 
     
     
         66 . The tag of  claim 63 , wherein the processor is further configured to
 receive a third command in the first set of commands, wherein the third command in the first set of commands causes the tag in the first state to be placed in a third state in a third group of tags; and wherein the processor is further configured to   receive a fourth command in the second set of commands, wherein the fourth command in the second set of commands causes the tag in the first state to be placed in the third state in the third group of tags.   
     
     
         67 . The tag of  claim 63 , wherein the processor is further configured to receive interrogation data, the interrogation data comprising the first set of commands to identify tags in the first state; and the second set of commands to identify tags in the second state, wherein the processor is further configured to detect a portion of the interrogation data representing at least a portion of an identification code, wherein the processor is further configured to compare the portion of the interrogation data to the at least the portion of the identification code imbedded in the memory in the tag, and wherein the processor is further configured to generate a response code if the portion of the interrogation data matches the at least a portion of the identification code imbedded in the memory in the tag.