KR200383978Y1 - Real Time Clock Device Generating Secure Clock - Google Patents

Abstract

The present invention relates to a real-time time generating device for generating a secure clock.

The present invention comprises an oscillator, divider, FOUT controller, interrupt controller, IIC bus interface circuit, time / date calculation unit, timer register, alarm register, and system controller, and provides real time time / date information. A secure clock time / date calculation unit is added to a device to provide a real time generation device that generates a secure clock that cannot be changed by an unauthorized user and generates a secure clock provided to an external computer.

According to the present invention, there is an effect that the user can generate a secure clock that cannot change the time / date arbitrarily and provide it to the computer.

Description

Real Time Clock Device Generating Secure Clock

The present invention relates to a real-time time generating device for generating a secure clock. More specifically, it includes an oscillator, divider, FOUT controller, interrupt controller, IIC bus interface circuit, time / date calculator, timer register, alarm register, and system controller to provide real-time time / date information. A secure clock time / date calculation unit is added to a time generating device to generate a secure clock which cannot be changed by an unauthorized user, and to generate a secure clock provided to an external computer.

A computer basically consists of an input / output device, a memory device, and a central processing unit (CPU). The computer processes the received information according to a predetermined algorithm and provides a result. With the development of computer-related technology, various tasks such as business work in the company, data exchange through a network such as the Internet, music listening, and movie watching are being processed by the computer. In connection with these various tasks, the computer often needs time information such as current time and date. Therefore, in general, a computer is equipped with a real time clock (RTC: Real Time Clock, RTC) in the form of a chip so that the time can be measured by itself.

The RTC is a device that generates a clock signal of a certain frequency and provides a clock function to the computer. A separate battery is connected to continue the time measurement even when the computer is not powered. RTC can provide hour / minute / second time information and day / week / month / year date information to the computer.Alarm function that informs the specific time set additionally and time intervals are measured. A timer function may be provided. The computer user can set / reset the RTC's time and date information as needed.

Meanwhile, with the development of digital technology, the creation, transmission, and exchange of digital contents consisting of text, voice, video, and video are becoming active, and unauthorized use of digital contents through the Internet community or peer-to-peer sharing sites is social. It is a problem. Therefore, Digital Rights Management (DRM) technology is emerging to protect the interests and rights of copyright related parties by preventing unauthorized use of digital contents. DRM technology is a concept that includes digital copyright management technology, software and security technology for copyright approval and enforcement, payment and payment technology, etc., to ensure that only legitimate users use the content and pay the appropriate fees.

As an example of applying the DRM technology, there is a time-bound license, which provides digital contents with a limited usage period to content users. For example, the downloaded digital content can be used for 20 days, after which the DRM technology can be applied to continue using the content at an additional fee. In order to limit the usage period of the digital content, a program for calculating the usage time is mounted in the content, and such a program uses time information provided by the RTC.

However, as described above, the conventional RTC allows the user to arbitrarily adjust the visual information. Therefore, by changing the visual information used by the usage restriction program mounted on the digital content, the content usage time can be extended or the content usage restriction can be removed. I have a serious problem.

In order to solve this problem, the present invention includes an oscillator, divider, FOUT controller, interrupt controller, IIC bus interface circuit, time / date calculator, timer register, alarm register, and system controller. By providing a secure clock time / date calculation unit to a real time generating device that provides a real time generating device for generating a secure clock that can be provided to an external computer by generating a secure clock that can not be changed by unauthorized users It aims to do it.

According to an object of the present invention, an RTC for generating a secure clock that cannot arbitrarily modulate time / date information, comprising: an oscillator for generating a reference clock signal of a specific frequency; A divider for dividing the reference clock signal generated by the oscillator; A FOUT controller for controlling the output signal to the FOUT pin; An interrupt controller for controlling to output the interrupt event signal through the / INT pin when an interrupt event signal is generated; An IIC bus interface circuit for transmitting and receiving data between the RTC and an external chip; Clock information received from the divider is counted, and time information including Hour, Minute, and Second information, and Day, Week, Month, and Year. A clock and date calculator for generating date information including information; A timer register for storing timer setting information for providing a timer function; An alarm register for storing alarm setting information for providing an alarm function; In addition to the time / date information provided by the time / date calculation unit, a clock signal received from the divider is counted, and secure time information including hour, minute, and second information, and secure information including day, week, month, and year information. A secure clock and calendar for generating date information; And controlling to perform a time / date calculation function, an alarm function, and a timer function in the RTC, and receiving a change request signal for a secure clock setting including a secure time / date change and a stop / reset. Authenticating whether the change request signal is a request by a secure clock change program authorized to change the secure clock setting, and controlling the secure time / date calculation unit to change the secure clock setting according to the authenticated change request signal. It provides an RTC for generating a secure clock, characterized in that it comprises a system controller (System Controller).

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related known configuration or function may obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a view showing the internal configuration of a conventional RTC.

As shown in FIG. 1, a conventional RTC includes an oscillator 100, a divider 110, a FOUT controller 120, an interrupt controller 130, and an IIC bus interface. Inter IC BUS Interface Circuit 140, Clock and Calendar 150, Timer Register 160, Alarm Register 170 and System Controller Controller 180, etc. may be configured.

The oscillator 100 generates a reference clock signal of a specific frequency and provides it to the RTC. The oscillator 100 may use a crystal oscillator that is effective for oscillating a fixed frequency and generally generates a reference clock signal of 32.768 kHz. The divider 110 divides the clock signal generated by the oscillator 100. Components of the RTC may require clock signals of various frequencies according to operating frequency settings, and the divider 110 divides the clock signals of the oscillators 100 to provide clock signals of frequencies used by the RTC.

The FOUT controller 120 controls the output signal to the FOUT pin. The FOUT controller 120 controls to output a signal of 32.768 kHz, which is a frequency generated by the oscillator 100, through the FOUT pin when the input signal level of the FOE pin is high, and through the FOUT pin when the input signal level of the FOE pin is low. Control to stop signal output.

The interrupt controller 130 controls to output the corresponding event signal through the / INT pin when an interrupt event occurs. For example, when the time when the alarm or timer function is set or when the time / date of the RTC is requested to be changed, an interrupt event occurs. The interrupt controller 130 sets an alarm signal, a timer signal, or a time update signal to the / INT pin. It will control the output to the outside.

The IIC bus interface circuit 140 serves as a data exchange passage between time / date data and various control signals between the RTC and external chips. The IIC bus is connected to the SCL and SDA pins. SCL is a pin that receives the clock frequency for IIC bus communication, and SDA is a pin that exchanges data with the outside using the clock frequency received from the SCL. When the IIC bus interface circuit 140 is operating in a high speed mode, the SCL pin can exchange data with a clock frequency of up to 400 kHz.

The time / date calculator 150 counts clock signals received from the divider 110 to calculate a current time, and includes time information and day information including hour, minute, and second information. ), Date, week, month, year are included. To this end, the time / date calculator 150 includes counters for calculating hours, minutes, seconds, days, weeks, months, and years.

The timer register 160 stores timer setting information for providing a timer function. The timer register 160 requests an interrupt event for generating a timer signal to the interrupt controller 130 when the time interval measured by the time / date calculator 150 reaches a time interval set in the timer register 160. The alarm register 170 stores alarm setting information for providing an alarm function. The alarm register 170 requests an interrupt event for generating an alarm signal to the interrupt controller 130 when the current time and date calculated by the time / date calculator 150 are set in the alarm register 170.

The system controller 180 controls the above-described components of the RTC to perform the time calculation function, the alarm function, the timer function, and the like, and receives an external control request signal to stop the operation of the RTC or to display the RTC time information and the like. Control to change the date information. To this end, the system controller 180 includes a control register, an extension register, a flag register, and the like, for transmitting a control signal.

2 is an exemplary diagram showing a register configuration of a conventional RTC.

As shown in FIG. 2, the conventional RTC has a plurality of registers to perform a real-time time generation function, and is configured to perform a specific operation for each register address.

Register addresses 0 to 6 are counters for calculating time information and date information, and RAM register 7 is a register allocated to input / output arbitrary data. Registers 8 to A are registers for setting the alarm time, and registers B and C are for setting the timer time. Extension register D contains the information to select the register to control for the operation of alarm function, time / date change function, etc. The flag register of E has the information to check whether or not it occurred by type of interrupt event. Is a register. The control register F is used to control the interrupt events for each type and to control the stop / reset of the counter for time / date calculation.

3 is a view showing the internal configuration of the RTC for generating a secure clock according to an embodiment of the present invention.

As shown in FIG. 3, the RTC according to a preferred embodiment of the present invention is a secure time / date calculator for providing the components of the conventional RTC shown in FIG. 1 and a Tamper Proof RTC function. Secure Clock and Calendar) 300 and the like. Here, detailed description of the same components as those of FIG. 1 will be omitted.

The secure time / date calculation unit 300 operates independently of the time / date calculation unit 150 to separate the clock signal received from the divider 110 from the time / date information provided by the time / date calculation unit 150. By counting, secure time information and secure date information are generated. To this end, the secure time / date calculation unit 300 includes separate counters for calculating hours, minutes, seconds, days, weeks, months, and years. That is, the secure time / date calculation unit 300 calculates time information using the Secure SEC register, the Secure MIN register, and the Secure Hour register, and uses the Secure DAY register, the Secure WEEK register, the Secure MONTH register, and the Secure YEAR register. Date information can be calculated.

Unlike the counter register of the time / date calculation unit 150, the above-described registers are configured to not change a setting value of a register when a time / date change or stop / reset request of an unauthorized user is received. That is, the existing control-related registers are set to manipulate the register values of the time / date calculator 150 and cannot access the registers of the secure time / date calculator 300.

Therefore, the system controller 180 of the present invention allocates a specific bit from the reserved bits except for the bits preset for control in the existing register for controlling the RTC as a control bit for controlling the secure time / date calculation unit 300. It may include a separate control register for controlling the secure time / date calculator 300.

When the system controller 180 receives a secure clock change request signal for changing a setting of the secure time / date calculation unit 180 such as a secure time / date change request or a stop / reset request from the outside, the system controller 180 receives a corresponding request signal. Authenticates whether it is a request signal from a secure clock change program authorized to change the secure clock setting.

To this end, the secure time / date calculation unit 300 and the secure clock change program have a built-in encryption code for authenticating the secure clock change authority. The system controller 180 receiving the setting change request signal for the secure clock compares the encryption code built into the secure time / date calculation unit 300 with the encryption code received from the secure clock change program, and if there is a match, it is authorized to change. Authentication is performed so that the time / date information of the secure time / date calculation unit 300 is changed according to the request signal.

On the other hand, if the encryption code received from the program that sent the change request signal does not match the password code embedded in the secure time / date calculation unit 300, the system controller 180 determines that the change request signal from an unauthorized user The unchangeable signal is output to the outside.

The time / date information generated by the secure time / date calculation unit 300 described above may be applied to calculate the use time of the digital content having a limited use period, and the secure clock change program may be shared only by the digital content provider. Do not allow the end user to change the secure clock.

The above description is merely illustrative of the present invention, and those skilled in the art to which the present invention pertains will be capable of various modifications without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present specification are not intended to limit the present invention but to describe the present invention, and the spirit and scope of the present invention are not limited thereto. The scope of the present invention should be construed by the claims below, and all the technologies within the equivalent scope should be construed as being included in the scope of the present invention.

As described above, according to the present invention, a digital content with a limited usage period is added to an existing RTC function that provides a clock function to a computer to generate a secure clock that an unauthorized user cannot change the time / date arbitrarily. There is an effect available to calculate the usage time of.

Therefore, the digital content can be protected by blocking the possibility of user's time manipulation of the digital content to which the Time-Bound license is applied.

1 is a view showing the internal configuration of a conventional RTC,

2 is an exemplary diagram showing a register configuration of a conventional RTC;

3 is a view showing the internal configuration of the RTC for generating a secure clock according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: oscillator 110: divider

120: FOUT controller 130: interrupt controller

140: IIC bus interface circuit 150: time / date calculation unit

160: timer register 170: alarm register

180: system controller 300: secure time / date calculation unit

Claims (5)

In a real time clock generating device (RTC: Real Time Clock, hereinafter referred to as 'RTC') for generating a secure clock that cannot arbitrarily modulate time / date information, An oscillator for generating a reference clock signal of a specific frequency; A divider for dividing the reference clock signal generated by the oscillator; A FOUT controller for controlling the output signal to the FOUT pin; An interrupt controller for controlling to output the interrupt event signal through the / INT pin when an interrupt event signal is generated; An IIC bus interface circuit for transmitting and receiving data between the RTC and an external chip; Clock information received from the divider is counted, and time information including Hour, Minute, and Second information, and Day, Week, Month, and Year. A clock and date calculator for generating date information including information; A timer register for storing timer setting information for providing a timer function; An alarm register for storing alarm setting information for providing an alarm function; In addition to the time / date information provided by the time / date calculation unit, a clock signal received from the divider is counted, and secure time information including hour, minute, and second information, and secure information including day, week, month, and year information. A secure clock and calendar for generating date information; And When the RTC is controlled to perform a time / date calculation function, an alarm function, and a timer function, and receives a change request signal for a secure clock setting including a secure time / date change and a stop / reset, Authenticating whether or not a change request signal is a request by a secure clock change program authorized to change the secure clock setting, and controlling the secure time / date calculation unit to change the secure clock setting according to the authorized change request signal. System Controller RTC generating a secure clock comprising a. The method of claim 1, The secure time / date calculation unit and the secure clock change program include an encryption code for authentication, and the system controller includes an encryption code embedded in the secure time / date calculation unit and an encryption code received from the secure clock change program. RTC for generating a secure clock, characterized in that to authenticate the change request signal. The method of claim 2, The system controller allocates a specific bit from the reserved bits except the bit set for control in the register for controlling the RTC as a control bit for controlling the secure time / date calculation unit or controls the secure time / date calculation unit. RTC for generating a secure clock, characterized in that it comprises a separate control register. The method of claim 3, wherein The secure time / date calculation unit includes a Secure SEC register, a Secure MIN register, and a Secure Hour register to calculate the secure time information, and includes a Secure DAY register, a Secure WEEK register, a Secure MONTH register, and a Secure YEAR register. RTC to generate a secure clock, characterized in that to calculate the information. The method of claim 4, wherein The system controller outputs an unchangeable signal by judging it as an unauthorized request signal if the encryption code embedded in the secure time / date calculation unit and the encryption code received from the program that sent the change request signal do not match. RTC to generate a secure clock.