Method for transmitting information over an intelligent low power serial bus

• US 5,675,811 A
• Filed: 08/18/1995
• Issued: 10/07/1997
• Est. Priority Date: 08/18/1995
• Status: Expired due to Term

• Current Assignee: Minero Digital, LLC (Daniel Francisco Perez)
• Original Assignee: General Magic, Inc.
• Inventors: Broedner, Walter F., Fadell, Anthony M., Perlman, Stephen G., Watkins, John E.
• Primary Examiner(s): Harvey, Jack B.
• Assistant Examiner(s): Seto, Jeffrey K.
• Application Number:
  US08/516,850
• Time in Patent Office: 781 Days
• Field of Search: 395/750, 395/284, 395/306, 395/309, 395/828, 395/834, 395/852
• US Class Current: 713/323
• CPC Class Codes: G06F 13/4291 using a clocked protocol

Abstract

A low power, single master, variable clock rate, daisy-chainable, serial bus connects a bus dispatch in a base station (master) to a chain of one or more daisy-chained peripheral devices (slaves). The bus has a bidirectional serial data line, a bidirectional clock line, unidirectional interrupt line, power and ground lines. Data and commands are sent from the base station to a peripheral device, and data is received from the peripheral device by the base station by configuring each peripheral device on the bus to receive data and clock signals from the base station in an idle mode of operation. Upon a command send being transmitted by the base station, all peripheral devices on the serial bus between the base station and an addressed peripheral device remain in the idle mode and the addressed peripheral device is connected to the bus so that clock and data signals on the bus to are passed to the peripheral device. When the peripheral devices on the bus are in the idle mode of operation, and the base station transmits a command get to an addressed peripheral device, the addressed peripheral device and all peripheral devices between the addressed peripheral device and the base station are reconfigured to transmit clock and data signals from the addressed peripheral device to the base station.

Claims

1. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus comprising:

configuring each peripheral device on said serial bus to receive data and clock signals from said base station in an idle mode of operation; and

maintaining said idle mode configuration for all peripheral devices on said serial bus between said base station and an addressed peripheral device upon a command send being transmitted over said serial bus by said base station.

2. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 1 further comprising:

reconfiguring an addressed peripheral device and all peripheral devices, on said serial bus between said addressed peripheral device and said base station, to transmit clock and data signals from said addressed peripheral device to said base station wherein said reconfiguring is performed upon said addressed peripheral device receiving a command to transmit data to said base station.

3. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 2 wherein each peripheral device includes upstream buffers coupled to said serial bus, downstream buffers coupled to said serial bus, and peripheral device buffers coupled to said upstream buffers;

and further wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises;

reconfiguring downstream buffers in a peripheral device connected directly to said base station by said serial bus so that clock and data signals can be received from another peripheral device on said serial bus.

4. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 3 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

reconfiguring upstream and downstream buffers in all peripheral devices on said serial bus between said addressed peripheral device and said peripheral device connected directly to said base station by said serial bus so that the downstream buffers pass clock and data signals to the upstream buffers.

5. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 4 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

reconfiguring upstream and peripheral buffers in said addressed peripheral device so that the peripheral buffers pass clock and data signals to the upstream buffers.

6. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 4 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

issuing a start of transmission command by said addressed peripheral device wherein in response to said start of transmission command, said downstream buffers in said peripheral device connected directly to said base station by said serial bus are coupled to said upstream buffers so that the downstream buffers pass clock and data signals to the upstream buffers.

7. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 6 further comprising:

transmitting clock and data signals from said addressed peripheral device to said base station over said serial bus.

8. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 7 further comprising:

reconfiguring said addressed peripheral device and all of said peripheral devices on said serial bus between said addressed peripheral device and said base station, upon said addressed peripheral device transmitting an end of transmission command.

9. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 8 wherein reconfiguring said addressed peripheral device and all of said peripheral devices on said serial bus between said addressed peripheral device and said base station, upon said addressed peripheral device transmitting an end of transmission command further comprises:

reconfiguring upstream and downstream buffers in all peripheral devices on said serial bus between said addressed peripheral device and said base station so that the upstream buffers pass clock and data signals to the downstream buffers.

10. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 9 further comprising:

reconfiguring said addressed peripheral device so that the upstream buffers pass clock and data signals to the downstream buffers upon said base station transmitting an end of transmission command.

11. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus comprising:

configuring each peripheral device on said serial bus between said base station and a last peripheral device on said serial bus in a mid-idle mode of operation wherein in said mid-idle mode of operation, a peripheral device receives data and clock signals from said base station and passes said data and clock signals to another peripheral device on said serial bus; and

configuring said last peripheral device in a last-idle mode of operation wherein in said last-idle mode, said last peripheral device receives data and clock signals from said base station and blocks transmission of said data and clock signals from further transmission over said serial bus.

12. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 11 wherein each peripheral device includes upstream buffers coupled to said serial bus, downstream buffers coupled to said serial bus, and peripheral device buffers coupled to said upstream buffers and further wherein configuring each peripheral device on said serial bus between said base station and said last peripheral device on said bus in a mid-idle mode of operation further comprises:

coupling said upstream buffers to said downstream buffers; and

disabling said peripheral device buffers.

13. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 12 wherein configuring said last peripheral device on said bus in a last-idle mode of operation further comprises:

disabling said downstream and said peripheral device buffers.

14. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 12 further comprising:

transmitting a command send over said serial bus by said base station wherein said command send includes an address for one peripheral device on said serial bus.

15. A method for sending data and commands to, and receiving data from peripheral devices connected to a base station by a serial bus as in claim 14 further comprising:

reconfiguring upstream buffers of said one peripheral device having said address so that said upstream buffers of said one peripheral device are coupled to said peripheral device buffers of said one peripheral device.

16. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 15 further comprising:

transmitting data from said base station to said one peripheral device over said serial bus.

17. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 16 further comprising:

transmitting an end of transmission command by said base station over said serial bus upon completion of transmitting data.

18. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 17 further comprising:

reconfiguring said one peripheral device to an idle-mode that is the same as the idle-mode of said one peripheral device prior to receipt of said send command.

19. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 13 further comprising:

transmitting a commend get over said serial bus by said base station wherein said common get includes an address for one peripheral device or said serial bus hereinafter referred to as said addressed peripheral device.

20. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 19 further comprising:

reconfiguring said addressed peripheral device and all peripheral devices, on said serial bus between said addressed peripheral device and said base station, to transmit clock and data signals from said addressed peripheral device to said base station.

21. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 20 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

reconfiguring downstream buffers in a peripheral device connected directly to said base station by said serial bus so that clock and data signals can be received from another peripheral device on said serial bus.

22. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 21 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

reconfiguring upstream and downstream buffers in all peripheral devices on said serial bus between said addressed peripheral device and said peripheral device connected directly to said base station by said serial bus so that the downstream buffers pass clock and data signals to the upstream buffers.

23. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 22 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

reconfiguring upstream and peripheral buffers in said addressed peripheral device so that the peripheral buffers pass clock and data signals to the upstream buffers.

24. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 22 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station further comprises:

issuing a start of transmission command by said addressed peripheral device wherein in response to said start of transmission command, said downstream buffers in said peripheral device connected directly to said base station by said serial bus are connected to said upstream buffers so that the downstream buffers pass clock and data signals to the upstream buffers.

25. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 24 further comprising:

transmitting clock and data signals from said addressed peripheral device to said base station over said serial bus.

26. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 25 further comprising:

reconfiguring said addressed peripheral device and all of said peripheral devices on said serial bus between said addressed peripheral device and said base station, upon said addressed peripheral device transmitting an end of transmission command.

27. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 26 wherein reconfiguring said addressed peripheral device and all peripheral devices on said serial bus between said addressed peripheral device and said base station upon said addressed peripheral device transmitting an end of transmission command further comprises:

reconfiguring upstream and downstream buffers in all peripheral devices on said serial bus between said addressed peripheral device and said bus station so that the upstream buffers pass clock and data signals to the downstream buffers.

28. A method for sending data and commands to and receiving data from peripheral devices connected to a base station by a serial bus as in claim 27 further comprising:

reconfiguring said addressed peripheral device so that the upstream buffers pass clock and data signals to the downstream buffers upon said base station transmitting an end of transmission command.