Method and device for managing information exchange between a main element, for example a NFC controller, and a set of at least two auxiliary elements

Patent metadata

Field	Value
Publication number	US-10244372-B2
Application number	US-201615335636-A
Country	US
Kind code	B2
Filing date	Oct 27, 2016
Priority date	Dec 15, 2010
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

Device, comprising a main element (ME) and a set of at least two auxiliary elements (SEi), said main element including a master SWP interface (MINT), each auxiliary element including a slave SWP interface (SLINTi) connected to said master SWP interface of said NFC element through a controllably switchable SWP link (LK) and management means (PRM, CTLM, AMGi) configured to control said SWP link switching for selectively activating at once only one slave SWP interface on said SWP link.

First claim

The invention claimed is:

1. A method of managing information to be exchanged between a main element having a master switchable single wire protocol (SWP) interface and a plurality of auxiliary elements, each auxiliary element having a slave SWP interface, the method comprising:
operating an SWP switch to selectively define an SWP link between only one slave SWP interface and the master SWP interface at any given time, and activate only the one slave SWP interface at the any given time;
the SWP switch comprising a first terminal coupled to the master SWP interface, and a plurality of second terminals coupled to respective ones of the plurality of slave SWP interfaces, and the SWP switch configured to electrically couple the first terminal to a respective second terminal of only the one SWP slave interface at the any given time and to simultaneously electrically decouple the first terminal from other ones of the plurality of second terminals at the any given time, wherein each of the plurality of auxiliary elements operates in a first power mode, or only one auxiliary element operates in a second power mode while each other auxiliary element is in an OFF state, or a first auxiliary element operates in the second power mode, wherein the second power mode has a power value lower than a power value of the first power mode, and wherein the SWP switch is configured to select the only one auxiliary element when the only one auxiliary element operates in the second power mode.

2. The method according to claim 1 , wherein the main element comprises a contactless element configured as a near field communication (NFC) controller, and each auxiliary element is configured as a secure element containing protected information.

3. The method according to claim 1 , further comprising forcing a part of the SWP link between each non-selected slave SWP interface and the SWP switch in a deactivated state.

4. The method according to claim 3 , further comprising controlling switching of the SWP switch when the SWP link is in a deactivated state.

5. The method according to claim 1 , wherein when the first auxiliary element operates in the second power mode, the first auxiliary element controls the SWP switch for selecting the first auxiliary element.

6. The method according to claim 5 , further comprising storing in the first auxiliary element a configuration indication, with the first auxiliary element controlling the SWP switch by using the configuration indication.

7. The method according to claim 6 , wherein the configuration indication is stored in the first auxiliary element when each of the plurality of auxiliary elements operates in the first power mode.

8. The method according to claim 5 , wherein when the first auxiliary element operates in the second power mode, the first auxiliary element controls powering of each other auxiliary element to place each other auxiliary element in the OFF state, and controls the SWP switch for selecting the first auxiliary element when operating in the second power mode.

9. The method according to claim 5 , wherein when the first auxiliary element operates in the second power mode, the first auxiliary element controls powering of a second auxiliary element configured to permit the second auxiliary element to operate in the second power mode, and the first auxiliary element controls the SWP switch for selecting the second auxiliary element operating in the second power mode.

10. The method according to claim 9 , further comprising storing in the first auxiliary element a configuration indication, with the first auxiliary element controlling the SWP switch by using the configuration indication, and wherein the first auxiliary element controls the powering of the second auxiliary element based on the configuration indication.

11. A device comprising:
a main element comprising a master single wire protocol (SWP) interface;
a plurality of auxiliary elements, each comprising a respective slave SWP interface;
an SWP switch comprising a first terminal coupled to the master SWP interface, and a plurality of second terminals coupled to respective ones of the plurality of slave SWP interfaces, the SWP switch configured to electrically couple the first terminal to a respective second terminal of only one SWP slave interface at any given time and to simultaneously electrically decouple the first terminal from remaining ones of the plurality of second terminals at the any given time; and
management circuitry configured to operate the SWP switch to selectively define an SWP link between the only one slave SWP interface and the master SWP interface at the any given time, and activate the only one slave SWP interface at the any given time, wherein each of the plurality of auxiliary elements operates in a first power mode, or only one auxiliary element operates in a second power mode while each other auxiliary element is in an OFF state, or a first auxiliary element operates in the second power mode, wherein the second power mode has a power value lower than a power value of the first power mode, and wherein the management circuitry is configured to operate the SWP switch to select the only one auxiliary element when the only one auxiliary element operates in the second power mode.

12. The device according to claim 11 , wherein said management circuitry comprises a controller configured to control the SWP switch.

13. The device according to claim 12 , wherein the controller is co-located with the main element.

14. The device according to claim 12 , wherein said management circuitry comprises a processor configured to place said SWP link in a deactivated state; and wherein said controller controls said SWP switch after said processor places said SWP link in a deactivated state.

15. The device according to claim 11 , further comprising first forcing circuitry configured to force a part of the SWP link coupled between each non-selected slave SWP interface and said SWP switch in a deactivated state.

16. The device according to claim 15 , wherein said first forcing circuitry comprises a plurality of pull-down resistors respectively coupled between said plurality of parts of said SWP link and a reference voltage.

17. The device according to claim 15 , wherein each of said plurality of auxiliary elements operates in the first power mode, or only one auxiliary element operates in the second power mode while each other auxiliary element is in the OFF state, the device further comprising a second forcing circuitry configured to force said SWP link into a configuration allowing selection of the only one auxiliary element when in the second power mode.

18. The device according to claim 17 , wherein said second forcing circuitry comprises a pull-down resistor coupled between a control input of said SWP switch and a voltage reference.

19. The device according to claim 11 , wherein each of said plurality of auxiliary elements operates in a first power mode, or a first auxiliary element operates in a second power mode, the device further comprising an auxiliary selector configured to control switching of said SWP switch for selecting said first auxiliary element when operating in the second power mode.

20. The device according to claim 19 , wherein said auxiliary selector comprises:
an auxiliary memory for storing a configuration indication; and
an auxiliary controller configured to control switching of said SWP switch based on the configuration indication.

21. The device according to claim 20 , wherein said auxiliary s

Assignees

• St Microelectronics Rousset
• St Microelectronics Gmbh

Inventors

• Rizzo Pierre
• Charles Alexandre
• Boehler Juergen
• Meziache Thierry

Classifications

• G06K7/10247

  issues specific to the use of single wire protocol [SWP] in NFC like devices · CPC title

• G06K7/10237

  the reader and the record carrier being capable of selectively switching between reader and record carrier appearance, e.g. in near field communication [NFC] devices where the NFC device may function as an RFID reader or as an RFID tag · CPC title

• H04W4/80 Primary

  Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication · CPC title

• G06K7/0008

  General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer · CPC title

• H04B5/0031

  Electricity · mapped topic