High density recording and play-back system with preamble and postlude patterns

Claim 1

A DATA PROCESSING SYSTEM FOR PROCESSING INFORMATION AND CLOCK PULSES IN A COMBINED FORM, COMPRISING A SOURCE OF CLOCK PULSES AT A PREDETERMINED FREQUENCY, SAID SOURCE INCLUDING THREE OUTPUT CONNECTIONS TO PROVIDE SIGNALS AT DIFFERENT PHASE RELATIONS RELATIVE TO EACH OTHER, A FIRST AND GATE INCLUDING CIRCUIT MEANS TO PASS A FIRST OUTPUT FROM SAID SOURCE, DELAY CIRCUIT MEANS CONNECTED TO PROVIDE A PREDETERMINED SIGNAL OUTPUT RESPONSIVE TO THE FIRST AND GATE AFTER AN INTERVAL OF TIME SUBSTANTIALLY EQUAL TO A PRESELECTED LENGTH FOR A PREAMBLE TO AN INFORMATION BLOCK, OUTPUT CIRCUIT MEANS TO PROVIDE COMBINED INFORMATION AND CLOCK SIGNALS, MEANS TO CONNECT THE OUTPUT OF THE FIRST AND GATE TO THE OUTPUT CIRCUIT MEANS, A SOURCE OF MULTIPLE CHANNEL DIGITAL INFORMATION INCLUDING AN INVERTED PARITY SIGNAL AND A DATA PRESENCE FLAG SIGNAL, A PLURALITY OF AND GATES HAVING CIRCUIT MEANS TO CONNECT EACH OF THE INFORMATION CHANNELS TO THE OUTPUT CIRCUIT MEANS RESPONSIVE TO THE DATA PRESENCE FLAG SIGNAL AND A SECOND OF THE OUTPUTS FROM SAID SOURCE OF CLOCK PULSES, A SEPARATE TRANSMIT CONTROL CIRCUIT MEANS TO ENABLE THE FIRST AND GATE AND TO CONNECT THE DATA PRESENCE FLAG SIGNAL TO THE OUTPUT CIRCUIT MEANS, A SECOND AND GATE INCLUDING CIRCUIT MEANS TO PASS A THIRD OF THE OUTPUTS FROM SAID SOURCE OF CLOCK PULSES RESPONSIVE TO SAID DELAY CIRCUIT MEANS FOR PROVIDING A REQUEST-FOR-DATA SIGNAL, A CIRCUIT MEANS FOR DEVELOPING A PREDETERMINED SIGNAL ON EACH CHANNEL INDICATIVE OF AN END-OF-PREAMBLE SIGNAL INCLUDING A THIRD AND GATE RESPONSIVE TO SAID DELAY CIRCUIT MEANS AND SAID SEPARATE TRANSMIT CONTROL CIRCUIT MEANS AND SAID DATA PRESENCE FLAG SIGNAL AND SAID RECORD OF THE OUTPUTS FROM SAID SOURCE OF CLOCK PULSES, CIRCUIT MEANS TO PROVIDE A POSTLUDE BEGINNING WITH AN END-OFBLOCK SIGNAL CONNECTED TO THE OUTPUT CIRCUIT MEANS FROM A FOURTH AND GATE RESPONSIVE TO SAID SECOND OF THE OUTPUTS FROM SAID SOURCE AND CLOCK PULSES AND SAID DATA PRESENCE FLAG SIGNAL AND SAID SEPARATE TRANSMIT CONTROL CIRCUIT MEANS AND TO A PREDETERMINED ONE OF SAID MULTIPLE CHANNELS, AND MEANS INCLUDING A CONNECTION FROM SAID CIRCUIT MEANS FOR DEVELOPING A PREDETERMINED SIGNAL ON EACH CHANNEL TO REMOVE THE ENABLE SIGNAL FROM SAID SECOND AND GATE SO THAT NO FURTHER REQUEST-FOR-DATA SIGNAL IS DEVELOPED.