Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
189 words
A central station, in a communication network for communicating with a plurality of response units in a sequence, comprising: means for transmitting to a response unit an interrogation signal requesting the response unit to read information contained therein, said means for transmitting preceding each transmission with a reset signal to ensure proper reception of the interrogation signal; receiver means for receiving return messages from a plurality of response units, said return messages having address, function and data portions; error detecting means coupled to said means for transmitting and to said receiver means for detecting errors in the return messages; said error detecting means, in response to an errorfree return message, causing said means for transmitting to transmit to the responding unit a signal indicative of errorfree reception and, in response to an erroneous return message, causing said transmitting means to retransmit an interrogation signal to the same response unit at least once; cycle control means, coupled to said means for transmitting, for initiating transmission to another response unit after transmission of either said signal indicative of error-free response or the last retransmission in response to an erroneous return message.
Claim 2
Dependent Claim
189 words
A central station, in a communication network for communicating with a plurality of response units in a sequence, comprising: means for transmitting to a response unit an interrogation signal requesting the response unit to read information contained therein, said means for transmitting preceding each transmission with a reset signal to ensure proper reception of the interrogation signal; receiver means for receiving return messages from a plurality of response units, said return messages having address, function and data portions; error detecting means coupled to said means for transmitting and to said receiver means for detecting errors in the return messages; said error detecting means, in response to an errorfree return message, causing said means for transmitting to transmit to the responding unit a signal indicative of errorfree reception and, in response to an erroneous return message, causing said transmitting means to retransmit an interrogation signal to the same response unit at least once; cycle control means, coupled to said means for transmitting, for initiating transmission to another response unit after transmission of either said signal indicative of error-free response or the last retransmission in response to an erroneous return message.
Claim 3
Dependent Claim
80 words
A central station as set forth in claim 1, further comprising: data detecting means coupled to said receiver means and said means for transmitting for detecting the presence of data in the return message; said data detecting means, in response to a no-data return message, causing said transmitting means to transmit immediately an interrogation signal to another response unit; and, in response to a data-present return message, causing said transmitting means to transmit in accordance with said error detecting means.
Claim 4
Dependent Claim
100 words
A central station as set forth in claim 2, further comprising: return message detecting means, coupled to said receiver means and said means for transmitting, for detecting the reception of a return message within a predetermined time interval after said interrogation signal is transmitted; said return message detecting means causing said means for transmitting to transmit to another response unit when no return message is received within said predetermined time interval and allowing said means for transmitting to transmit in accordance with said error detecting and data detecting means when a return message is received within said predetermined time interval.
Claim 5
Dependent Claim
97 words
A central station as set forth in claim 1, further comprising: return message detecting means, coupled to said receiver means and said means for transmitting, for detecting the reception of a return message within a predetermined time interval after said interrogation signal is transmitted; said return message detecting means causing said means for transmitting to transmit to another response unit when no return message is received within said predetermined time interval and allowing said means for transmitting to transmit in accordance with said error detecting means when a return message is received within said predetermined time interval.
Claim 6
Dependent Claim
42 words
A central station as set forth in claim 1 wherein said error detecting means comprises: address and function coincidence detecting means for comparing the address and function transmitted to a response unit with the address and function received from that response unit.
Claim 7
Dependent Claim
27 words
A central station as set forth in claim 5 wherein said error detecting means further comprises: parity checking means for checking said data portions for proper parity.
Claim 8
Dependent Claim
49 words
A central station as seT forth in claim 1 wherein said signal indicative of error-free reception comprises the address of the responding unit and a clear function code which clears the data storage registers of the responding unit; and wherein said transmitting means retransmits said interrogation signal only once.
Claim 9
Dependent Claim
43 words
A central station as set forth in claim 7 wherein said cycle control means comprises transmission completion sensing means for sensing the complete transmission of said address and clear function code and initiating transmission to another response unit upon sensing a complete transmission.