Single wire bus interface

Abstract

Embodiments disclosed herein address the need for a single wire bus interface. In one aspect, a device communicates with a second device via a single wire bus using a driver for driving the bus with a write frame comprising a start symbol, a write indicator symbol, an address, and data symbols. In another aspect, the device receives one or more data symbols on the single wire bus during a read frame. In yet another aspect, a device communicates with a second device via a single wire bus using a receiver for receiving a frame on the single wire bus comprising a start symbol, a write indicator symbol, an address, and one or more data symbols, and a driver for driving return read data associated with the address when the write indicator identifies a write frame. Various other aspects are also presented. These aspects provide for communication on a single wire bus, which allows for a reduction in pins, pads, or inter-block connections between devices.

1 . A device, operable to communicate with a second device via a single wire bus, comprising: 
 a driver for driving the single wire bus with a write frame, the write frame comprising a start symbol, a write indicator symbol, one or more symbols indicating an address, and one or more data symbols.    
   
   
       2 . The device of  claim 1 , further comprising: 
 a receiver for receiving one or more data symbols on the single wire bus during a read frame;    and wherein:    the driver further drives the single wire bus for one or more portions of the read frame and releases the single wire bus for one or more portions of a read frame, the driven portion of the read frame comprising a start symbol, a read indicator symbol, and one or more symbols indicating an address, the released portion of the read frame comprising one or more data symbols surrounded by pause symbol durations.    
   
   
       3 . The device of  claim 1 , wherein zero or more idle symbols are transmitted on the single wire bus.  
   
   
       4 . The device of  claim 3 , wherein an idle symbol is driven by the driver.  
   
   
       5 . The device of  claim 3 , further comprising a pull device, the pull device for driving the single wire bus to the idle symbol.  
   
   
       6 . The device of  claim 1 , further comprising a keeper for keeping a value on the single wire bus.  
   
   
       7 . A device, operable to communicate with a second device via a single wire bus, comprising: 
 a receiver for receiving a frame on the single wire bus, the frame comprising a start symbol, a write indicator symbol, one or more symbols indicating an address, and one or more data symbols when the write indicator symbol identifies a write frame;    a driver for driving return read data on the single wire bus when the write indicator symbol identifies a read frame, the return read data associated with the address.    
   
   
       8 . A device, comprising: 
 a port for connecting to a single wire bus;    a signal generator for generating a first single signal comprising one or more idle symbols, a start symbol, a write indicator symbol, one or more symbols indicating an address, and one or more data symbols when the write indicator symbol indicates a write;    a driver for driving the first signal on the single wire bus through the port in a first mode and releasing the single wire bus through the port in a second mode;    a receiver for receiving a second signal from the single wire bus through the port, the second signal being active during a portion of time the driver is operating in the second mode, when the write indicator symbol indicates a read, the second signal comprising return read data in response to the address.    
   
   
       9 . The device of  claim 8 , wherein the port comprises a pad.  
   
   
       10 . The device of  claim 8 , wherein the port comprises a pin.  
   
   
       11 . The device of  claim 8 , wherein the port comprises an intra-chip connection.  
   
   
       12 . The device of  claim 8 , wherein the port comprises an inter-chip connection.  
   
   
       13 . A system, operable to communicate with a second device via a single wire bus, comprising: 
 a single wire bus;    a first device comprising a driver for driving the single wire bus with a write frame, the write frame comprising a start symbol, a write indicator symbol, one or more symbols indicating an address, and one or more data symbols; and    a second device comprising a receiver, connected to the single wire bus, for receiving the write frame.    
   
   
       14 . The device of  claim 13 , wherein: 
 the first device further comprises a receiver for receiving one or more data symbols on the single wire bus during a read frame;    and wherein the driver of the first device further drives the single wire bus for one or more portions of the read frame and releases the single wire bus for one or more portions of a read frame, the driven portion of the read frame comprising a start symbol,    a read indicator symbol, and one or more symbols indicating an address, the released portion of the read frame comprising one or more data symbols surrounded by pause symbol durations.    
   
   
       15 . The device of  claim 14 , wherein the second device further comprises a driver for driving return read data on the single wire bus when the write indicator symbol identifies a read frame, the return read data associated with the address, and wherein the receiver further receives a frame on the single wire bus, the frame comprising a start symbol, a write indicator symbol, one or more symbols indicating an address, and one or more data symbols when the write indicator symbol identifies a write frame.  
   
   
       16 . A method for communication on a single wire bus comprising: 
 transmitting a start symbol;    transmitting a write indicator symbol;    transmitting one or more symbols indicating an address;    transmitting one or more data symbols when the write indicator symbol indicates a write access; and    receiving one or more data symbols when the write indicator symbol indicates a read access.    
   
   
       17 . The method of  claim 16 , further comprising transmitting one or more idle symbols.  
   
   
       18 . A method for communication on a single wire bus comprising: 
 receiving a start symbol;    receiving a write indicator symbol;    receiving one or more symbols indicating an address;    receiving one or more data symbols when the write indicator symbol indicates a write access; and    transmitting one or more data symbols when the write indicator symbol indicates a read access.    
   
   
       19 . The method of  claim 18 , further comprising storing the received data symbols in accordance with the received address when the write indicator symbol indicates a write access.  
   
   
       20 . The method of  claim 18 , further comprising retrieving data in accordance with the received address for transmission when the write indicator symbol indicates a read access.  
   
   
       21 . A device comprising: 
 means for transmitting a start symbol on a single wire bus;    means for transmitting a write indicator symbol on the single wire bus;    means for transmitting one or more symbols indicating an address on the single wire bus;    means for transmitting one or more data symbols when the write indicator symbol indicates a write access on the single wire bus; and    means for receiving one or more data symbols when the write indicator symbol indicates a read access on the single wire bus.    
   
   
       22 . A device comprising: 
 means for receiving a start symbol on a single wire bus;    means for receiving a write indicator symbol on the single wire bus;    means for receiving one or more symbols indicating an address on the single wire bus;    means for receiving one or more data symbols when the write indicator symbol indicates a write access on the single wire bus; and    means for transmitting one or more data symbols when the write indicator symbol indicates a read access on the single wire bus.    
   
   
       23 . Computer readable media operable to perform the following steps: 
 transmitting a start symbol;    transmitting a write indicator symbol;    transmitting one or more symbols indicating an address;    transmitting one or more data symbols when the write indicator symbol indicates a write access; and    receiving one or more data symbols when the write indicator symbol indicates a read access.    
   
   
       24 . Computer readable media operable to perform the following steps: 
 receiving a start symbol;    receiving a write indicator symbol;    receiving one or more symbols indicating an address;    receiving one or more data symbols when the write indicator symbol indicates a write access; and    transmitting one or more data symbols when the write indicator symbol indicates a read access.