Command queuing for multimedia storage devices

BACKGROUND OF THE INVENTION

Portable electronic devices such as cellular telephones and personal digital assistants are now available with the capability to present multimedia. Examples of multimedia include graphics or pictures, video, MP3 audio files, and combinations thereof.

The Multi-Media Card Association and the SD Association promote an industry-standard that specifies electrical and physical specifications for multi-media devices for use with portable communications equipment such as cellular telephones. When used with a cellular telephone, a so-called multi-media device can provide ring tones, games, pictures, video, audio files and the like. A problem with multi-media devices such as multi-media cards (hereafter referred to as multi-media devices), however, is that an electronic device to which they are coupled, can effectively slow down because of the rate at which commands to the multi-media devices are executed and the data rate at which information is sent to and received from such devices.

By way of example, in the prior art, a multi-media device interface couples a processor or other controller for a portable electronic device such as a portable radio or cellular phone, to a multi-media device. When the portable electronic device sends a command to the multi-media device, it passes through a multi-media device interface, which sends the data request to the multi-media device. If the controller for the portable device requests a data transfer, it will usually specify the amount of data that should be read as well. The multi-media device will send a response to the data request and begin sending data. The amount of data specified by the controller for the portable electronic device will be sent by the multi-media device. The ability to send commands to the multi-media device at any time would improve the performance of portable communications devices to which a multi-media device is coupled.

US patent no. <patcit id="pcit0001" dnum="US6466804B"><text>US 6,466,804</text></patcit> describes an apparatus enabling multiple client devices to access a SIM card, coupled to a server device, along a local link, that includes a SIM card interface and a router unit. The SIM card interface couples the SIM card to the server device, formats the commands from the client devices for transmission to the SIM card, and formats responses to the commands for transmission from the SIM card to the client devices. The router unit routes the commands from the server device to the SIM card interface, and routes the responses to the commands for transmission along the local link from the SIM card to the client devices. A broadcast message is transmitted by the router unit along the local link to the client devices in response to detecting a physical presence signal transmitted by the SIM card interface in response to the SIM card being coupled to the SIM card interface.

SUMMARY

In accordance with aspects of the invention, there is provided a portable electronic device and a method in a portable electronic device, as recited in the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

<ul id="ul0001" list-style="none" compact="compact"><li><figref idref="f0001">FIG. 1</figref> shows a portable electronic device and a multi-media storage device in accordance with one embodiment of the invention.</li><li><figref idref="f0002">FIG. 2</figref> shows one example of a multi-media device interface as part of a portable communications device in accordance with one embodiment of the invention and a multi-media storage device coupled to the multi-media device interface.</li><li><figref idref="f0003">FIG. 3</figref> shows one example of a block diagram depiction of a method for coupling a multi-media storage device to a personal communications device in accordance with one embodiment of the invention.</li><li><figref idref="f0004">FIG. 4</figref> shows the continuation of one example of a block diagram depiction of a method for coupling a multi-media storage device to a personal communications device in accordance with one embodiment of the invention.</li><li><figref idref="f0005">FIG. 5</figref> shows one embodiment of a multi-media device interface with electronic devices.</li></ul>

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

<figref idref="f0001">FIG. 1</figref> shows a portable electronic device 10 embodied as a cellular telephone and a multi-media storage device 16. The multi-media storage device 16 is preferably embodied as a circuit card 12-2. As shown in <figref idref="f0001">FIG. 1</figref>, the card 12-2 can be inserted into a mating receptacle 12-1 in the portable electronic device 10 where electrical contacts of the card 12-2 make electrical contact with complementary electrical contacts with the portable electronic device 10 but which are not shown in <figref idref="f0001">FIG. 1</figref> for clarity.

For purposes of claim construction, the term "portable electronic device" should be construed to encompass all radio transmitter, radio receiver and transceiver devices that provide either one-way or two-way communications capability, regardless of the type of modulation (analog, CDMA, TDMA, GSM, et al.) or the frequency spectrum in which they operate (800 MHz., 900 MHz., and higher) but also including optical or infrared signals as well as acoustic signals. Examples of radio devices include two-way radios, pagers and GPS devices. The term "portable electronic device" should also be construed to include personal digital assistants (PDAs), MP3 players, digital cameras and "Internet appliance," which can include any device by which Internet access (web browsing, e-mail or other forms of packetized data) is sent and received. In a preferred embodiment, the portable electronic device 10 includes a radio device, such as a cellular telephone, which is considered to include the radio circuitry by which two-way communications can be provided.

With respect to a cellular telephone embodiment, the term "portable electronic device" includes the radio communications circuitry, i.e., the transmitter and/or receiver and/or transceiver, used in portable and mobile two-way cellular devices, regardless of the frequency spectrum in which such devices operate or the type of modulation they use.

<figref idref="f0002">FIG. 2</figref> shows a preferred embodiment of a multi-media device interface 18 (i.e., an interface for a multi-media device) as part of the portable electronic device 10. In <figref idref="f0002">FIG. 2</figref>, the portable electronic device 10 is a cellular telephone and includes a radio 26. For a cellular telephone, the radio 26 would include a radio transmitter/receiver or transceiver by which two-way communications would be provided.

The multi-media device interface 18 operatively couples the portable electronic device 10 to a multi-media storage device 16 (also referred to herein as a "multi-media device") so that the portable communications device can effectively send commands to the multi-media storage device 16 while the multi-media storage device 16 is sending data to the portable device 10.

In a preferred embodiment, a first processor 30 (hereafter the "MCU") of the portable electronic device 10 sends a command to the multi-media device 16, requesting a file. The MCU 30 will notify or inform a second processor 28, of the size of the file requested from the multi-media device 16. Thereafter, the second processor 28 will monitor data that it receives from the multi-media device 16.

Information-bearing signals, i.e., data signals, can be exchanged between (i.e., sent to and received from) the multi-media storage device 16 and the portable electronic device 10 according to specifications of the Multi-Media Card Association but also according to the SD Card Association Although the preferred embodiment of the invention transfers information between the multi-media storage device 16 and the portable electronic device 10 via electrical signals, alternate and equivalent methods of transferring information would include the use of infrared signals, acoustic, optical signals or radio frequency signals. Infrared data transmission techniques and circuitry, acoustic data transmission techniques and circuitry and RF data transmission techniques and circuitry, are well-known to those of ordinary skill in the art.

By way of example, the multi-media storage device 16 might store audio files for use as ringer tones by the portable electronic device 10. The multi-media storage device 16 might also store pictures, video streams or MP3 audio files for playback on the portable electronic device 10 display screen, output from a speaker or other input/output (I/O) device 24 with which the portable electronic device 10 is equipped. An even more general embodiment of portable electronic device 10 includes devices identified in <figref idref="f0005">FIG. 5</figref>, which include devices such as a CD player, an MP3 player, a DVD player, an Internet appliance or a PDA, (all identified by reference numeral 100) which are equipped with the multi-media device interface 18 described herein.

As the file transfer from the multi-media storage device 16 proceeds, a second command can be issued to the multi-media storage device 16 from the MCU 30 whereupon the multi-media device interface 18 will receive the second command and store it in a command queuing buffer 42 (also known as "buffer 42") until such time that the multi-media storage device 16 can execute it.

The multi-media device interface 18 reduces processing overhead associated with data transfer between the multi-media storage device 16 and the portable electronic device 10. A principal function of the multi-media device interface 18 is to enable a processor in the portable electronic device 10 that is controlling the multi-media storage device 16, to issue commands to the multi-media storage device 16, even when the multi-media storage device 16 is unable to process them. In the embodiment shown in <figref idref="f0002">FIG. 2</figref>, the multi-media device interface 18 enables the MCU 30 to issue a first command to the multi-media storage device 16.

An example of a command to the multi-media storage device 16 would be to request the transfer of a file from the multi-media storage device 16 to the portable electronic device 10. During the time that the multi-media storage device 16 executes the first command, the multi-media device interface 18, enables the MCU 30 to issue another command to the multi-media storage device 16. The multi-media device interface 18 includes a command queuing buffer 42 where the second command is queued until the multi-media storage device 16 is able to execute the second command. In a preferred embodiment, a queued, i.e., "second" command will be executed by the multi-media storage device 16 after a previously-issued, i.e., "first" command is completed. The MCU 30 does not need to wait until one command to the multi-media storage device 16 has been executed before issuing another command.

In a preferred embodiment, the multi-media device interface 18 includes a command processor 32, which receives information 34 (commands, but also possibly including data) from at least one of the processors 28 or 30 of the portable electronic device 10. After the command processor 32 receives a command from the processor MCU 30, it forwards those commands to a multi-media interface controller 36, which can be embodied as a processor, such as a microcontroller or microprocessor as well as a DSP or combinational and/or sequential logic. The command processor 32 is preferably embodied as combinational logic, a gate array or an application specific integrated circuit.

In a preferred embodiment, the MCU forms a command by configuring registers in the command processor 32. The command processor 32 provides for error correction by way of a cyclic redundancy check or CRC, added to the commands issued to the multi-media storage device 16 from the MCU 30.

Commands to the multi-media storage device 16 are passed by the command processor 32.The multi-media interface controller 36 controls when the command is sent to the multi-media device 16. If the multi-media storage device 16 is capable of executing it, the multi-media interface controller 36 can forward a command directly to the multi-media storage device 16. The interface 36 also queues commands to the multi-media storage device 16 in the command queuing buffer 42.

The command processor 32 receives responses from the multi-media storage device 16 and validates those responses, typically by checking a cyclic redundancy check or CRC. attached to the response. The command processor 32 will notify the portable communications device controllers, that a response was received from the multi-media storage device 16 and that the multi-media storage device 16 is available to execute another command.

Another function of the multi-media interface controller 36 is to monitor the execution of the commands sent to the multi-media storage device 16. The multi-media interface controller 36 monitors the status or execution of commands by testing the responses 38 that are received from the multi-media storage device 16 in response to commands 40 that are sent to it.

The command queuing buffer 42, which is coupled to the command processor 32 as well as the multi-media face controller 36, stores commands to the multi-media device until they can be executed. In the preferred embodiment, the command queuing buffer 42 is embodied by 48-bit shift register. Commands can be written into the buffer 42 in parallel but shifted out in a serial fashion. Alternate embodiments include using a semi-conductor random access memory (RAM) device, however, in such an embodiment, sending information serially would require some sort of parallel-to-serial conversion.

As set forth above, the command queuing buffer 42 stores commands from the MCU 30 until such time the multi-media storage device 16 is able to execute them. The determination of when the multi-media storage device 16 can execute another command is determined in the second processor 28 notifying the MCU 30 that a previously-issued command has been completed.

By way of example, the controller/MCU 30 may request a file from the multi-media storage device 16. In order to do so, the controller/MCU 30 will issue a command that will be received by the command processor 32. The command processor can determine the status of the multi-media storage device 16 by monitoring current or most recent responses 38. If, for instance, the multi-media storage device responses 38 indicate that the multi-media storage device 16 is not busy, the command to send a file will be sent to the queuing buffer 42. The multi-media interface controller 36 can gate or transfer the command 40 to transfer a file from the multi-media storage device 16 by selecting the command from the queuing buffer 42 and causing the command queuing buffer 42 to write the command 40 to the multi-media storage device 16.

By tracking or monitoring the execution of commands sent to the multi-media storage device 16, the controller 36 substantially unburdens the controller/MCU 30 and the second processor (e.g., a DSP) 28 of the portable electronic device 10, freeing them to perform other tasks. The controller/MCU 30 does not need to wait until a data transfer is complete before issuing a command to the multi-media device 16.

Included within the multi-media device interface 18 is a data processing controller 46. The data processing controller 16 receives data 44 from the storage device 16 and converts it to an appropriate-sized parallel format. In instances where data must be sent to the multi-media storage device 16 from the portable electronic device 10, the data processing controller 46 can perform a parallel to serial conversion.

The data processing controller 46 includes an amount of random access memory, or RAM, into which, data from the multi-media storage device 16 can be stored pending the availability of the second processor/DSP 28 to transfer the data into the radio 26 or elsewhere in the portable electronic device 10.

<figref idref="f0003">FIG. 3</figref> shows a method of coupling a portable electronic device to a multi-media storage device 16.

At step 302, a multi-media device interface 18 will receive a command for the multi-media storage device 16. In step 304, the command to the multi-media storage device will be queued in a buffer until the multi-media storage device 16 concludes executing a previously-issued command. By queuing the command to the multi-media storage device, the portable electronic device can perform other tasks instead of waiting until the multi-media storage device is available.

In step 306, the conditions for sending a queued command are tested. When the multi-media storage device 16 is able to execute the command issued to it, as determined by monitoring the data from or to the multi-media storage device 16, a queued command is sent to the multi-media storage device 16 in step 308.

At step 310 in <figref idref="f0004">FIG. 4</figref>, the execution of the command by the multi-media storage device 16 is monitored and/or tested by the multi-media device interface 18 by monitoring and/or testing data that is received by the multi-media device interface 18 from the multi-media device 16. The responses 38 received from the multi-media storage device 16 (sometimes embodied as the cessation thereof) will indicate when a previously-issued command is completed. In step 308, part of the testing of data from the multi-media storage device 16 is the testing integrity is to insure that data from the multi-media storage device 16 is received intact, which in some embodiments is by way of checksums added to streams of data, parity bits added to data bytes or cyclic redundancy checks, all of which are considered to be equivalent embodiments of data integrity testing.

Data is transferred to and from the multi-media device in a serial fashion. The portable electronic device 10 on the other hand uses parallel data. Accordingly, in step 312, data that is received from the multi-media storage device 16, is converted to a serial form. Conversely, in step 314, data directed to the multi-media storage device 16 from the portable electronic device 10 is converted from a parallel format.

Those of skill in the art will appreciate that by coupling a portable electronic device 10, such as a portable phone, pager, or personal digital assistant to a multi-media storage device through an intelligent controller or interface, the processing power of the portable communications device can be freed to perform other tasks with the multi-media device interface monitoring the status of commands and the availability of the multi-media storage device to respond.

While the principles of the invention have been described above in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation on the scope of the invention.