Drum electronics control interface and protocol for recording/reproducing apparatus

Abstract

A method and apparatus for allowing communication between a stationary circuit and circuitry in motion with respect to the stationary circuit is presented. Communication is achieved and verified by transmitting a clock signal and a control signal in synchronization with the clock signal over separate clock and control transformer channels between the stationary circuit and the moving circuitry.

1 . A method for allowing communication between a stationary circuit and a moving circuit in a recording apparatus, said moving circuit in motion relative to said stationary circuit and a recording medium, comprising: 
 sending a clock signal from said stationary circuit over a clock transformer channel to said moving circuit;    sending a write control signal from said stationary circuit over a control transformer channel to said moving circuit in synchronization with said clock signal;    receiving, by said stationary circuit, a verification signal from said moving circuit over said control transformer channel in synchronization with said clock signal, said verification signal indicating if said control signal as received by said moving circuit is correct; and    if said write control signal as received by said moving circuit is correct, sending a write data signal from said stationary circuit over a write transformer channel that is independent of said control transformer channel to said moving circuit for recording onto said recording medium.    
   
   
       2 . The method of  claim 1 , further comprising: 
 if said write control signal as received by said moving circuit is correct, sending an execute command signal in synchronization with said clock signal over said control transformer channel to said moving circuit, said execute command instructing said moving circuit to execute a write command indicated by said write control signal.    
   
   
       3 . The method of  claim 1 , further comprising: 
 if said verification signal indicates that said write control signal as received by said moving circuit is incorrect, sending a discard signal from said stationary circuit over said control transformer channel to said moving circuit in synchronization with said clock signal; and    receiving, by said moving circuit, said discard signal from said stationary circuit over said control transformer channel in synchronization with said clock signal and ignoring said write control signal as received by said moving circuit.    
   
   
       4 . The method of  claim 1 , wherein: 
 said verification signal comprises said write control signal as received by said moving circuit.    
   
   
       5 . The method of  claim 1 , wherein: 
 said verification signal indicates that said write control signal as received by said moving circuit is correct if it matches said write control signal as sent to said moving circuit.    
   
   
       6 . The method of  claim 1 , wherein: 
 said stationary circuit comprises a stator of a drum; and    said moving circuit comprises a rotor of a drum which rotates around said stator.    
   
   
       7 . A data recording apparatus, comprising: 
 a stationary circuit;    a moving circuit, said moving circuit which moves relative to said stationary circuit;    a write transformer channel which couples a write data signal from said stationary circuit to said moving circuit for recording onto a recording medium;    a clock transformer channel which couples a clock signal from said stationary circuit to said moving circuit;    a control transformer channel independent of said write transformer channel which couples a control signal in synchronization with said clock signal from said stationary circuit to said moving circuit; and    a moving circuit controller which receives and processes commands indicated by said control signal in synchronization with said clock signal.    
   
   
       8 . The apparatus of  claim 7 , further comprising: 
 a stationary circuit controller which generates said control signal.    
   
   
       9 . The apparatus of  claim 8 , wherein: 
 said control transformer channel couples control signals in synchronization with said clock signal from said moving circuit to said stationary circuit.    
   
   
       10 . The apparatus of  claim 8 , wherein: 
 said control transformer channel couples a verification signal in synchronization with said clock signal from said moving circuit to said stationary circuit, said verification signal indicating whether said control signal as received by said moving circuit is correct.    
   
   
       11 . The apparatus of  claim 10 , wherein: 
 said control transformer channel couples an execute signal in synchronization with said clock signal from said stationary circuit to said moving circuit if said verification signal indicates that said control signal as received by said moving circuit is correct.    
   
   
       12 . The apparatus of  claim 8 , wherein: 
 said stationary circuit comprises a stator of a drum; and    said moving circuit comprises a rotor of a drum which rotates around said stator.    
   
   
       13 . A recording apparatus comprising: 
 a stationary circuit;    a moving circuit, said moving circuit which moves relative to said stationary circuit;    a clock transformer channel which couples a clock signal from said stationary circuit to said moving circuit;    a control transformer channel which couples control signals in synchronization with said clock signal from said stationary circuit to said moving circuit and from said moving circuit to said stationary circuit;    a stationary circuit controller in said stationary circuit which generates a write control signal to be sent to said moving circuit over said control transformer channel in synchronization with said clock signal;    a moving circuit controller in said moving circuit which receives said write control signal in synchronization with said clock signal, generates a verification signal indicating whether said received write control signal is correct to be sent to said stationary circuit over said control transformer channel in synchronization with said clock signal, and executes a write control command indicated in said write control signal;    a write transformer channel independent of said control transformer channel which couples a write data signal from said stationary circuit to said moving circuit; and    a write driver on said moving circuit which, if enabled, records write data indicated by said write data signal onto a recording medium.    
   
   
       14 . The apparatus of  claim 13 , wherein: 
 said moving circuit controller enables said write driver if said write control command indicated in said write control signal is a write data command.    
   
   
       15 . The apparatus of  claim 13 , wherein: 
 said stationary circuit controller generates an execute signal to be sent to said moving circuit over said control transformer channel in synchronization with said clock signal if said verification signal indicates that said received write control signal is correct; and    said moving circuit controller in said moving circuit only executes said write control command indicated in said write control signal upon receiving said execute signal.    
   
   
       16 . The apparatus of  claim 13 , wherein: 
 said stationary circuit comprises a stator of a drum; and    said moving circuit comprises a rotor of a drum which rotates around said stator.