Communication card with three operational states

1. A communication card with three operational states, comprising:

a controller;

a flash storage unit, coupled with said controller, for storing data used by said controller;

a wireless modem, coupled with said controller, for transmitting and receiving data over a wireless network in response to instructions received from said controller;

a battery, coupled with said controller, with said flash storage unit and with said wireless modem, for supplying power to said controller, to said flash storage unit, and to said wireless modem; and

a connector, coupled with said controller, for connecting the communication card to a shell host and to a device host; wherein the communication card (i) operates in a standalone mode when said connector is not connected to a host, (ii) functions as a master when said connector is connected to the shell host, providing display information to the shell host in the form of screen shots, and (iii) functions as a slave when said connector is connected to the device host, enabling the device host to operate the communication card.

2. The communication card of claim 1 further comprising circuitry for determining whether said connector is connected to a host and, if so, whether the host is the shell host or the device host.

3. The communication card of claim 1 wherein said battery is used to power the shell host when the shell host is connected thereto.

4. The communication card of claim 1 wherein the shell host has its own battery, and wherein said battery is charged by the shell host's battery when the shell host is connected to said connector.

5. The communication card of claim 1 further comprising a USB connector coupled with said controller.

6. The communication card of claim 1 wherein said wireless modem comprises an audio player.

7. A method for determining the operational state of a communication card, comprising:

providing a communication card that has three operational states, namely, (i) the communication card in a standalone mode (State I), (ii) the communication card connected to a shell host (State II), and (iii) the communication card connected to a device host (State III);

monitoring a first signal on the communication card; and

if the first signal has a voltage level lower than a first designated threshold, then concluding that the communication card is in State I;

otherwise, concluding that the communication card is connected to a host, and:

monitoring a second signal on the communication card; and

if the second signal has a voltage level lower than a second designated threshold, then concluding that the communication card is in State II and controlling the communication card to operate as a master for the shell host;

otherwise,

concluding that the communication card is in State III and controlling the communication card to onerate as a slave for the device host.

8. The method of claim 7 wherein the first signal is a battery voltage.

9. The method of claim 8 wherein the first designated threshold is 0.5V.

10. The method of claim 7 wherein the second signal is a battery voltage.

11. The method of claim 10 wherein the second designated threshold is 0.5V.

12. A computer readable storage medium storing program code for causing a computing device to determine the state of a communication card that has three operational states, namely, (i) the communication card in a standalone mode (State I), (ii) the communication card connected to a shell host (State II), and (iii) the communication card connected to a device host (State III), by:

monitoring a first signal on the communication card; and

if the first signal has a voltage level lower than a designated threshold, then concluding that the communication card is in State I;

otherwise, concluding that the communication card is connected to a host, and:

monitoring a second signal on the communication card; and

if the second signal has a voltage level lower than the designated threshold, then concluding that the communication card is in State II and controlling the communication card to onerate as a master for the shell host;

otherwise,

concluding that the communication card is in State III and controlling the communication card to onerate as a slave for the device host.

13. A communication card with three operational states, comprising:

a card connector for connecting a communication card to a shell host and to a device host, comprising a plurality of pins, the pins comprising:

a connector for incoming and outgoing audio signals;

a connector for a power supply; and

a universal serial bus (USB) connector;

a communication bus, wherein (i) no signals are routed to the communication bus when the card operates in a standalone mode (State I), (ii) secure digital (SD) card signals are routed to the communication bus when the card is connected to the shell host (State II) using a set of functionalities assigned to said connector nins, with the card functioning as master, and (iii) SD card signals are routed to the communication bus when the card is connected to the device host (State III) using a different set of functionalities assigned to said connector pins, with the card functioning as slave; and

circuitry for automatically detecting whether the card is operating in State I, State II or State III.

14. The communication card of claim 13 wherein said circuitry senses voltages across said connector pins.

15. The communication card of claim 13 wherein said different set of functionalities comprises SD communication functionalities.

16. The communication card of claim 13 wherein said shell host provides a user interface for the communication card.

17. The communication card of claim 16 wherein the shell user interface comprises at least one speaker.

18. The communication card of claim 16 wherein the shell user interface comprises a microphone.

19. The communication card of claim 13 wherein said device host is a media player.

20. The communication card of claim 13 wherein said device host is a digital camera.