Car telephone apparatus

SWEDEN (₁₂) PATENT CERTIFICATE (ni C2 (id 520 372 (19) SE (51) International class ⁷

H04B 1/38

<img file="SE520372C2_D0001.tif" />

PATENT AND REGISTRATION (21)

<td> (45) (41)</td><td>Patent granted Application widely available</td><td colspan="2"> 2003-07-01 1993-06-17</td><td>number 9203738!</td>

<td> (22)</td><td>The patent application was filed</td><td> 1992-12-11</td><td colspan="2">Application received as:</td>

<td> (24)</td><td>effective date</td><td> 1992-12-11</td><td></td><td></td>

<td> (62)</td><td>Tribal application number</td><td></td><td>X</td><td>Swedish patent application</td>

<td> (86)</td><td>International filing day</td><td></td><td></td><td>completed international patent application</td>

<td> (86)</td><td>Filing date for the application</td><td></td><td></td><td>with number</td>

<td></td><td>on European patent</td><td colspan="2"></td><td>converted European patent application</td>

<td> (83)</td><td colspan="2">Deposition of microorganism</td><td>LJ</td><td>with number</td>

<td> (30)</td><td>priority Data</td><td></td><td></td><td></td>

1991-12-16 JP 03/331665 (73) PATENT HOLDER Matsushita Electric Industrial Co Ltd, Osaka JP (72) INVENTOR Takehiko Hayashi, Yokohama-shi JP Albihns Stockholm AB

CAR PHONE DEVICE (56) CALLED PUBLICATIONS:

EP 459 488 (H04M 1/72), US 5,060,295 (H04B 1/10), US 4,811,377 (H04Q 7/04) (57) SUMMARY:

(74) REPRESENTATIVE (54) TITLE

The present invention provides a superior car telephone device which can erase the contents of a memory without disassembling the memory of the car telephone device, that is, with the memory mounted in the device, and which can also rewrite the contents of the memory by external transmission of modification data. The car telephone device comprises an electrically erasable and rewritable non-volatile memory microcircuit, a control means for controlling the erase / rewrite operation on the memory microcircuit, a means for transmitting and collating external write data, and a means for external controlling a series of these control operations.

<img file="SE520372C2_D0002.tif" />

The numbers in brackets indicate international identification code, INID code. Letters in clamps indicate international document code.

520 372

Summary

The present invention provides a superior car telephone device which can erase the contents of a memory without disassembling the memory of the car telephone device, that is, with the memory mounted in the device, and which can also rewrite the contents of the memory by external transmission of modification data. The car telephone device comprises an electrically erasable and rewritable non-volatile memory microcircuit, a control means for controlling the erase / rewrite operation on the memory microcircuit, a means for transmitting and collating external write data, and a means for external controlling a series of these control operations.

520 372

The present invention relates to a car telephone device.

A prior art car telephone device usually uses an erasable programmable read-only memory (EPROM) of the type ultraviolet radiation as a non-volatile memory means for storing software for controlling the device.

Thus, when it is desirable to change the contents of the already written software in the EPROM, it has been necessary to first delete the contents of the EPROM and then rewrite the data contents by means of a special writing means. Further, the erasure operation of the written content requires ultraviolet rays to be radiated onto the EPROM itself, which may adversely affect other portions located in the vicinity of the EPROM. In order to avoid the influence of the ultraviolet rays on the other parts and to improve its function, it becomes necessary to disassemble the EPROM once from the car telephone device. For easy detachable mounting of the EPROM, it is known technique to mount the EPROM microcircuit itself on a base.

Fig. 4 is a schematic block diagram of a control system of a prior art car telephone device. In the drawing, the illustrated control system comprises a central processor (CPU) 21 for controlling the car telephone device, an EPROM 22 as a non-volatile memory for storage therein of software describing a series of control procedures or controls, a direct access memory (RAM) 23 as a memory for temporary storage therein of arithmetic operations and control execution data, an input port (I / O) 24 for direct control of peripheral devices within the car telephone device; and a socket 25 for mounting the EPROM 22. Various types of control of the car telephone device are performed sequentially under the control of the central processor (CPU) 21 according to the contents of the EPROM 22.

520 372

Summary of the Invention

However, the aforementioned prior art car telephone device has had a problem in that when switching software or control means of the central processor is desired, it is necessary to once separate from the car telephone device the EPROM in the form of an integrated memory circuit with the software program stored therein, to delete the program content by irradiation of ultraviolet rays on the disconnected EPROM, to rewrite a modified software program in the EPROM using a special writing means, and then re-mount the EPROM at the socket of the car telephone assembly, whereby the change of control means requires a lot of time.

It is an object of the present invention to provide a superior car telephone device which can solve the aforementioned problem of the prior art, which can erase the contents of a program in an integrated memory circuit and which can rewrite the old program contents into new program contents by transferring modified data from the outside of the integrated memory circuit, eliminating the need to disconnect the integrated memory circuit from the car telephone device.

According to one aspect of the present invention, the above object is achieved by providing a car telephone device comprising an electrically erasable and rewritable non-volatile memory, control means for controlling the erase / rewriting operation of the memory, means for transmitting and collating externally input write data, and actuating means control of a series of these control operations.

With the aforementioned device of the present invention, the contents of the memory already written therein are erased, externally input rewrite data is transmitted and stored temporarily, rewriting control for memory rewriting

520 372 is performed, and then the temporarily stored information is read out for collation of rewrite data. As a result, when changing the program content is desired, the rewriting of the memory can advantageously be performed without disassembling the memory from the car telephone device.

Brief description of the drawings

Fig. 1 is a schematic block diagram of a control system of a car telephone device according to an embodiment of the present invention;

Figures 2 and 3 are a flow chart for explaining the rewrite operation of a non-volatile memory 12; and Fig. 4 is a schematic block diagram of a control system of a prior art car telephone device.

Description of the preferred embodiment

Referring to Fig. 1, a device of a car telephone device according to an embodiment of the present invention is shown.

In Fig. 1, the illustrated device comprises a central processor (CPU) 11, a non-volatile memory 12 of an electrically erasable type, a direct access memory (RAM) 13, an input / output port (I / O) 14, an asynchronous serial interface 15, a masked read memory (ROM) 16 included in the central processor (CPU) 11, and a switch transistor 17 for supplying a high voltage to the non-volatile memory 12 at the time of a write mode. As the electrically erasable non-volatile memory 12, an electrically erasable and programmable read-only memory (ROM) (EEPROM) is used instead of a conventional EPROM, the embodiment of which is explained below.

In the case of a flash-type EEPROM, the written contents of the EEPROM can be instantly electrically erased when a voltage of about 12V is supplied from outside to

520 372

The EEPROM and a predetermined deletion command are input to the EEPROM. Then, when the EEPROM is subjected to a predetermined write control, the memory contents of the EEPROM can be rewritten.

In the present embodiment, a program (which will hereinafter be referred to as the charging program) for controlling the erase and write operation on the EEPROM flash-type with the above function, as well as a program for asynchronous serial interface communication, is stored in the mask read memory (ROM) in advance. 16 of the central processor (CPU) 11. Therefore, a program for controlling the car telephone device need not be written in the non-volatile memory 12, so that when a supply voltage is first turned on, the charging program of the mask reading memory (ROM) 16 is first activated, whereby the central processor (CPU) 11 can independently control a series of erasure and write operations on the non-volatile memory 12. When input and output commands for controlling the write operation on the non-volatile memory 12 are performed from the outside of the car telephone device through the asynchronous serial interface 15, the non-volatile memory 12 can be rewritten without disassembling the non-volatile memory 12 from the car telephone device. In the following, a sequence of write operations will be explained with reference to a flow chart of Figures 2 and 3.

1) Confirmation of microcircuit content

When the power supply of the car telephone device is switched on, this causes the software stored in the read-only memory (ROM) of the central processor (CPU) 11 to be activated (step SI).

As a result, the central processor (CPU) 11 once reads the contents of the non-volatile memory 12 through a bus line of the central processor (CPU), collates through such collation means as sum check code (step S2) to check the presence or absence of data written in the non-volatile memory 12 (step S3), and notifies the controller

520 372 on its inspection results through the serial external interface 15.

2) Entering a write command 5

When the central processor (CPU) 11 confirms that the contents of the non-volatile memory 12 are already written, the central processor (CPU) immediately activates the software held in the non-volatile memory 12 (step S4) to assess whether the memory

12 has received a write command from the serial interface 15 (step S5). In determining the absence of receiving the write command, the central processor (CPU) starts its predetermined control operations.

Upon determining that the non-volatile memory 12 has not yet been written, the central processor (CPU) 11 notifies the controller of its performance through the serial external interface 15 (step S7) and becomes ready for an input (step S8).

Even in the case where the contents of the non-volatile memory 12 have already been written, when a change of the content is desired, the controller, based on the central process (CPU) 11, notifies a write request through the serial interface 15.

3) Transfer of write data

The controller enters a command through the serial external interface 15 to activate the write software of the central processor (CPU) 11 and then transmits write data, whereby the central processor (CPU) 11 whenever it receives write data sequentially stores this write data in the direct memory (RAM) 13 (step S6) .

4) Deleting the memory contents

The central processor (CPU) 11 controls switch transistor 17 through the input / output port (I / O) 14 so that a high voltage necessary for erasing the program is supplied from the transistor

520 372 to a predetermined contact of the non-volatile memory 12 (step S9) so that the central processor (CPU) 11 enters an erase command to the memory 12 through the bus line of the central processor (CPU) 11 to perform the erase operation on the memory 12 (step S10) .

5) Writing the memory

In a manner similar to the above, memory 12 is put into its write mode. The data temporarily stored in the direct memory (RAM) 13 is sequentially entered into the memory 12 through a bus line under the control of the central processor (CPU) 11 (step S11). When the write operation is completed, the central processor (CPU) 11 turns off the switch transistor 17 through the input / output port (I / O) 14.

6) Collation of the written content

After rewriting the contents of the memory 12 through the aforementioned means, the central processor (CPU) 11 reads out the contents of the non-volatile memory 12 and remotely notifies the controller of the triggered contents through the serial interface 15 (step S13).

The central processor (CPU) 11 collates the external write data with the read-out data (step S14) to assess compliance or non-conformity between these data (step S15). Finally, in determining consistency between these data, the central processor (CPU) 11 writes in the microcircuit 12 a sum check code and a flag indication of the already written microcircuit.

In determining non-compliance between the data, the central processor (CPU) 11 again deletes the contents of the memory 12 and repeats any subsequent operations already explained above.

As can be seen from the foregoing embodiment, the present invention has the effect that the electrically erasable,

520 372 the non-volatile memory instead of the conventional non-volatile memory of the type of ultraviolet radiation erasure and the writing means for the memory, and the means for external transmission of writing data to it are also provided in the car telephone device, the rewriting operation of the program of the non-volatile memory being realized the memory is mounted in the car telephone device.

Furthermore, since restrictions on mounting the memory in the car telephone device can be eliminated, the car phone device can be made correspondingly smaller in size and thickness.

520 372