JPH10271575A - Communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discriminate the propriety of data written in a nonvolatile memory. SOLUTION: A transmission signal is received by a transponder resonance circuit section 8 in a transponder 7. AC power is supplied by a power signal of the received signal and required data are written in a nonvolatile memory 12 based on contents of a command of the received signal. In this case, the write of data is controlled such that an end mark is written to a 3rd address after a corresponding address of the written data, a check sum is written to a first address after the address for the written data and then the data are written to the corresponding address.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for receiving a transmission signal in which pulse data is superimposed on a power signal, generating operating power in response to the reception of the power signal, and storing required data in a nonvolatile manner based on the transmission signal. TECHNICAL FIELD The present invention relates to a communication device having a writing function for writing to a volatile memory.

[0002]

For example, in a communication device that performs non-contact two-way communication between a vehicle and a key, a transmission that transmits a transmission signal in which pulse data is superimposed on a power signal to the vehicle is transmitted. There has been considered a configuration in which a transponder is provided as a receiving means on a key side such as an ignition key or a door key.

[0003] When a key is inserted into a key cylinder on the vehicle side and a transmission signal is given from a transmitter, the transponder generates operating power in response to the reception of the power signal, and the transponder enters an active state with the operating power. As a result, a response signal is returned according to the signal content of the reception signal, or data is written to a nonvolatile memory provided in the transponder.

By the way, in the above-mentioned case, if the key is removed while the data is being written in the non-volatile memory of the transponder, the supply of the operating power is stopped, so that the data may not be written normally. In this case, it is impossible to determine whether the final data written in the nonvolatile memory is correct.

The present invention has been made in view of the above circumstances, and an object of the present invention is to supply electric power from a transmitting unit to a receiving unit by electromagnetic coupling and to store necessary data in a nonvolatile memory based on a transmission signal. It is an object of the present invention to provide a communication device capable of determining whether data written in a nonvolatile memory is correct in a communication device in which writing is performed.

[0006]

According to the present invention, there is provided a transmitting means for transmitting a transmission signal in which pulse data is superimposed on a power signal, receiving the transmission signal and generating operating power in response to the reception of the power signal. And a receiving unit having a write function of writing required data to a nonvolatile memory based on the transmission signal, when writing data to the nonvolatile memory, a third address from a corresponding address of the data to be written. Write the end mark to
Next, write control means for controlling a write operation so as to write a sum check to the first address from the corresponding address of the data to be written, and thereafter to write the data to the corresponding address, and to write the data content of the nonvolatile memory to the address It is characterized in that a data correct / non-judgment means for reading in order and judging the sum check when the end mark is read continuously is provided.

In this configuration, when data to be written this time is data D (n) and data already written is data D (n-1), data D (n-2),. The data contents in the memory are as shown in FIG.

That is, when writing the data D (n), the address to which the data D (n) is to be written is "n". Then, the write control means writes an end mark from the address "n" to the address "n + 3", which is the third address, as the first write. As the second write, the address “n”
, A sum check is written to address “n + 1”, which is the first address, and data D (n) is written to address “n” as a third write. The sum check includes the last data D (n-n-
Exclusive OR of lower bits of 1) and the current data D (n) is written as check data. Note that the end mark is not written in the address “n + 2”, and the previous end mark is used as it is (the end mark is continuous as data).

After the above-mentioned writing is completed, the data correct / non-determining means reads the data contents of the non-volatile memory in order of address, and judges the sum check when the end mark is read continuously. That is, the exclusive OR of the data D (n) written this time and the data D (n-1) preceding it and the check data of the sum check are compared, and if the sum check is correct (if they match), Data D (n) and previous data D
(N-1),... Are determined to be correct data,
If the check is not correct, the data D (n) is determined to be incorrect data, and the data D (n-1),... Are determined to be correct data. This makes it possible to determine whether the data in the nonvolatile memory is correct or not.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. First, FIG. 2 shows a schematic configuration of a communication device. Transceiver 1 as transmission means
Is provided in the vehicle, and the transponder 7 as a receiving means having a writing function is provided in, for example, an ignition key. The reader / writer 15 is provided in an office or the like.

As shown in FIG. 3, the transceiver 1 comprises a control circuit 2 mainly composed of a microcomputer, a power amplifier 3, a resonance circuit section 4, a detection circuit 5, and an amplifier 6. The resonance circuit section 4 includes an antenna coil. 4a and a resonance capacitor 4b. A control program is stored in the control circuit 2 of the transceiver 1, and the control circuit 2 turns on and off the power amplifier 3 based on the control program, as shown in FIG. The transmission signal on which the data pulse is superimposed is transmitted from the antenna coil 4a.

The transponder 7, as shown in FIG.
Transponder coil 8a and resonance capacitor 8b
Transponder resonance circuit section 8, power supply circuit 9, detection circuit 10, control circuit 11 mainly composed of microcomputer, nonvolatile memory 12, CR oscillation circuit 13
And a modulation circuit 14.

Now, when the key is inserted into a door key cylinder or an ignition key cylinder on the vehicle side and the antenna coil 4a of the transceiver 1 on the vehicle side and the transponder coil 8a on the key side are electromagnetically connected, the vehicle The transmission signal from the antenna coil 4a on the key side is supplied to the transponder coil 8a on the key side in a non-contact manner.

In the transponder 7 on the key side, the transmission signal is received by the transponder resonance circuit section 8. This received signal is the same as in FIG. In this case, AC power is supplied by the power signal. That is, this AC power is rectified and sufficiently smoothed by the power supply circuit 9 and is made constant voltage (voltage Vd
d), and the constant voltage power supply is supplied to each circuit. The detection circuit 10 shapes the resonance waveform, which is the reception signal of the transponder resonance circuit section 8, with a time constant smaller than that of the power supply circuit 9, and outputs a pulse data waveform.

When the control circuit 11 of the transponder 7 detects the input of SOM (Start of Message) among the pulse data, it starts reading the data and thereafter determines the contents of the command. Then, based on the result of this determination, data such as an ID code is read from the nonvolatile memory 12 or required data such as operation data is written. The details of this write control will be described later.

When an ID code or the like is returned from the transponder 7, the impedance of the transponder resonance circuit section 8 is changed by the modulation circuit 14 in accordance with the data to be returned, and transmitted to the transceiver 1 on the vehicle side. 5
A reply signal shown in (b) is generated.
This return signal is provided to the control circuit 2 via the detection circuit 5 and the amplifier 6 on the vehicle side. In this case, the control circuit 2
When the SOM input is detected after the frame synchronization, the reading of the reply data is started, and the response content from the control circuit 11 on the key side is determined based on the subsequent reply signal.

On the other hand, as shown in FIG. 4, the reader / writer 15 has basically the same configuration as the transceiver 1, that is, the control circuit 1 mainly including a microcomputer.
6, a power amplifier 17, a resonance circuit section 18 having an antenna coil 18a and a resonance capacitor 18b, a detection circuit 19, and an amplifier 20, and further connected to a power supply circuit 21 for generating operating power from an external power supply, and a personal computer. A serial I / F 22 is provided.

Although not shown, the reader / writer 15
An insertion portion into which a key is inserted is provided, and when the key is inserted and the antenna coil 18a of the reader / writer 15 and the transponder coil 8a on the key side are electromagnetically connected, the insertion portion of the reader / writer 15 is A transmission signal (a signal in which pulse data is superimposed on a power signal) from the antenna coil 18a is provided to the key-side transponder coil 8a in a non-contact manner.

In the transponder 7 on the key side, as in the case of the communication with the transceiver 1, AC power is supplied by the power signal, and a reply signal is transmitted in accordance with the command content of the transmission signal. Reply to reader / writer 15

Now, the control circuit 11 of the transponder 7
Has a writing function and operates as a writing control means. Further, the reader / writer 15 operates as a data correct / non-determining means. The details are as follows. It is assumed that data is written in the nonvolatile memory 12 of the transponder 7, as shown in column A of FIG. In this case, data D (0) is stored at address “0”, data D (1) is stored at address “1”, and address “2” is stored at address “1”.
Is written with data D (2), "sum check" is written at address "3", and "end mark" is written at addresses "4" and "5". In this case, for example, "end mark"
Is a bit configuration in which all bits are "1". In "sum check", the most significant bit is set to "0", and exclusive OR is performed with bits excluding the most significant bits of two data before the sum check. Each data D has a bit configuration that does not take all bits “1”.

When a transmission signal having a command content of "write data D (3)" is given from the transceiver 1 to the transponder 7, the control circuit 11 of the transponder 7
Performs a write control operation as shown in column B of FIG. When writing the data D (3), the address to which the data D (3) is to be written is “3”. Thus, the control circuit 11 writes an end mark from address “3” to address “6”, which is the third address, as the first write. As the second writing,
A sum check is written to address “4” which is the first address from address “3”, and data D (3) is written to address “3” as a third write. Note that the end mark is not written at the address “5”, and the previous end mark is used as it is (the end mark is continuous as data).

When data is read from the non-volatile memory 12 of the key transponder 7 by the reader / writer 15, the control circuit 16 of the reader / writer 15 reads the data content of the non-volatile memory 12 in order of address, and the end mark is read. When it is read continuously,
Judge the check. That is, if the exclusive OR of the lower bits of the data D (3) written this time and the data D (2) preceding it matches the check data of the sum check (if the sum check is correct), the current data D (3) (3) and previous data D (2) to D (0)
Is determined to be correct data, and if they do not match (if the sum check is not correct), data D (3) is determined to be incorrect data, and data D (2) to D (0) are correct data. It is determined that there is. This makes it possible to determine whether the data in the nonvolatile memory is correct or not.

For example, if the key is removed while writing the end mark of address "6", the end mark of address "6" will not be written normally. In such a case, the control circuit 1 of the reader / writer 15
No. 6 finds the end marks of addresses “4” and “5” and determines the sum check of address “3”. Since this sum check is before writing, the data D
(2) to D (0) are determined to be correct.

If the key is removed while the sum check of address "4" is being written, the sum check of address "4" will not be written normally. In such a case, the control circuit 16 of the reader / writer 15 finds the end marks of the addresses “5” and “6” and converts the data of the addresses “2” and “3” (the previous sum check) into the address “ Although the sum check of "4" is determined, but does not match, the data of address "3" (previous sum check) is determined to be erroneous data, and data D (2) to D (0) are correct. Is determined.

Furthermore, the data D of the address "3"
If the key is removed while writing (3), data D (3) at address "3" will not be written normally. In such a case, the control circuit 16 of the reader / writer 15 finds the end marks of the addresses "5" and "6", and finds the data of the addresses "2" and "3" (this wrong data is contained. ), The sum check of the address “4” is determined. However, since they do not match, the data of the address “3” is determined to be erroneous, and the data D (2) to D (0) are determined to be correct. .
Thus, it can be determined whether the data written in the nonvolatile memory 12 is correct. Therefore, it is very suitable for a communication device without a key removal prevention function.

Here, the reason why the previous end mark is used as it is as the end mark of the upper address of the two end marks is as follows. That is, if the end mark is written at address “5” after writing the end mark at address “6” in column B of FIG. 6, if the key is removed at this time, the end mark is written here. Therefore, there is no guarantee that the end of the data is read, so that the end of the data cannot be detected when the reader / writer 15 reads the next end mark.

At the time of key initialization, it is preferable to write an end mark at the third address from the first address where data is to be written. Although the control circuit 11 of the transponder 7 has a function of writing data to the nonvolatile memory 12 of the transponder 7, a write control means for controlling the writing (control of writing the end mark and the sum check separately to a designated address) ) May be provided in the control circuit 2 of the transceiver 1 or the reader / writer 15. In this case, a write control signal is superimposed on a transmission signal transmitted by the transceiver 1 or the reader / writer 15. Further, the right / wrong determination means may be provided on the transceiver 1 side. Furthermore, in the present embodiment, the vehicle-side transceiver 1, the key-side transponder 7, and the office-side reader / writer 15 are provided. 7 or the office-side reader / writer 15 and the key-side transponder 7
May be combined with

[0028]

According to the present invention, as is apparent from the above description, when power is supplied from the transmitting means to the receiving means by electromagnetic coupling, and required data is written to the nonvolatile memory based on the transmission signal. Then, it can be determined whether the data written in the nonvolatile memory is correct.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electrical configuration of a transponder showing one embodiment of the present invention.

FIG. 2 is a block diagram showing an overall schematic configuration.

FIG. 3 is a block diagram of an electrical configuration of a transceiver.

FIG. 4 is a block diagram of an electrical configuration of the reader / writer.

FIG. 5 is a diagram showing a communication waveform.

FIG. 6 is a diagram showing data contents of a nonvolatile memory;

FIG. 7 is a diagram showing data contents of a nonvolatile memory used for explaining the operation of the present invention;

[Explanation of symbols]

1 is a transceiver (transmission means), 2 is a control circuit, 4 is a resonance circuit section, 7 is a transponder (reception means), 8 is a transponder resonance circuit section, 11 is a control circuit (write control means), and 12 is non-volatile. Memory, 15 is a reader / writer,
Reference numeral 16 denotes a control circuit (correction / rejection determination means).

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Sadao Kokubu 1 Noda, Toyota, Oguchi-machi, Oguchi-machi, Niwa-gun, Aichi Prefecture Tokai Rika Electric Works, Ltd.

Claims (1)

[Claims] 1. A transmitting means for transmitting a transmission signal in which pulse data is superimposed on a power signal, receiving the transmission signal, generating operating power in response to receiving the power signal, and generating a required power based on the transmission signal. A communication device comprising: a receiving unit having a write function of writing data to a nonvolatile memory; wherein when writing data to the nonvolatile memory, an end mark is written to a third address from a corresponding address of the data to be written, A write control means for controlling a write operation to write a sum check to a first address from a corresponding address of the data to be written and thereafter to write the data to the corresponding address is provided, and reads data contents of the nonvolatile memory in order of addresses. ,
When the end mark is read continuously, the thumb
A communication device comprising a data right / wrong determining means for determining a check.