JPS6250942A - Information transmission system - Google Patents

Abstract

PURPOSE:To make the control of a battery unnecessary and to transmit the information correctly by providing a comparator to compare the electric power source voltage of a capacitor with a reference voltage and operating a CPU only when the electric power source voltage is larger than the reference voltage, at two memory devices. CONSTITUTION:The information is communicated from a memory device 1 through a memory device 2 through a signalline 101. At the device 1, the information is accumulated at a RAM 3 and outputted from an I/O circuit 4. On the other hand, to hold the contents of the RAM 3, the electric power source voltage accumulatd at a capacitor 5 of a large capacitor is used. At the device 2, the information sent through the signal line 101 is received by an I/O circuit 7 and sent by a CPU 8 to a RAM 9. A comparator 10 judges whether or not the sent information is normal. At the comparator 10, a reference voltage VD is generated by a constant voltage diode 12 and applied on one input terminal of a calculating amplifier 13. When an electric power source voltage VC of a terminal 17 is lowered than the voltage VD, the output of the amplifier 13 comes to be zero and thus, the CPU 8 does not communicate the information.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention provides a method for transmitting the output of an information generating device to the first
It relates to a method of temporarily storing the stored contents in a second storage device and transmitting the stored contents to a second storage device.

(Prior Art) Conventionally, RAM has been used as the first storage device. Devices with battery-backed memory have been used, but with this method, there were problems with battery management, resulting in people not noticing when the battery was depleted, or when it was lost and lost due to theft. If the first storage device is handed over to three parties, there is a possibility that the entire contents of the RAM will be read.

(Problems to be Solved by the Invention) The above-mentioned information transmission method has problems with the confidentiality and reliability of the information stored in the RAM, so it is not possible to carry the entire first storage device with confidence. The purpose of the present invention is to store the information transmitted from the information generating device in the first storage device, store the power supply voltage in a large capacity capacitor and maintain it, and use it to transmit the information. 1st
When connecting the first storage device and the second storage device, the power supply voltage of a large capacitor is compared with the reference voltage, and if the power supply voltage of the capacitor is lower than the reference voltage, all information will not be transmitted. An object of the present invention is to provide an information transmission method configured to eliminate the above-mentioned drawbacks and obtain highly confidential and reliable data. The system is configured to transmit information from an information generating device to a first storage device, and further to transmit information from the first storage device to a second storage device.

In the above, the first storage device includes a t-th first RAM that stores information transmitted from the information generation device, and a first RAM.
It is equipped with a t-th large-capacity capacitor that supplies the entire power supply voltage to maintain all the contents of the AM, and a first I/O circuit for performing input/output operations to the first RAM.

On the other hand, the second storage device includes a second I/O circuit for inputting and outputting information between the first storage device and the second storage device.
A second circuit for storing information input from the I/O circuit of
RAM, a second I/O circuit, and a CPU for processing information from the second RAM.

Further, the first or second storage device includes a comparator for comparing the power supply voltage of the capacitor with the total reference voltage and operating the CPU only when the power supply voltage is higher than the reference voltage.

(Embodiment) Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the information transmission system according to the present invention. In FIG. 1, l is a first storage device, 2 is a second storage device, 3 is a first 1'LAM,
4 is the first I/O circuit, 5 is a capacitor, 6 is a resistor,
7 is the second I/O circuit, 8 is the CPU, 9 is the second RAM
1/O is a comparator, 11 is a resistor, 12 is a Zener diode, and 13 is an operational amplifier.

In FIG. 1, information is transmitted from a first memory device 1 to a second memory device 2 via a signal line /O1 t-. In the first storage device 1, information is stored in the first ELAM 3 and multiple outputs from the first I/O circuit 4. On the other hand, in order to maintain the contents of the first (2) RAM 3, the power supply voltage stored in the large capacity capacitor 5 is used.

In the storage device f12 of WX2, the information sent via the signal line /O1 is received by the I/O circuit 7 of the digital assistant 2, and is sent to the CP
It is sent to the second RAM9 using U5'. On the other hand, whether the information sent from signal /O1 is normal or not,
This is determined by the comparator/O. That is, capacitor 5
The voltage across 0 is applied to the + side input terminal of the operational amplifier 13 via the resistor 6, the terminal 14, the signal line /O2, and the terminal 17t-. On the other hand, in the comparator IO, the resistor 11. and a constant voltage diode 12i to create a reference voltage vDt'', and an operational amplifier 1
3 is applied to one side input terminal.

Therefore, when the power supply voltage Vo at the terminal 17 generated based on the power supply voltage t appearing across the capacitor 5 is lower than the reference voltage VD, the output of the operational amplifier 13 becomes O level υ, which is 0PUs. There is pressure and control to ensure that information is not transmitted in exchange for money.

FIG. 2 shows a diagram 11 in which the first storage device shown in FIG. 1 receives information from the information generating device 20.
Fig. 72. The output of the information generating device 1zo is connected to the signal line/
O1 is stored in the first RAM 3 via the first I/O circuit 4. At this time, the voltage Vot is inputted from the terminal 14, and the capacitor 5 is also charged via the resistor 6.

FIG. 3 is a block diagram showing a second embodiment of the information transmission system according to the present invention. In Figure 3, the first
Like symbols and like numbers in the figures represent like elements as in FIG.

3 differs from FIG. 1 in that the comparator /O for comparing the voltage of the capacitor 5 with the reference voltage VD is provided in the first storage device 1. In this case, the comparator/
The power supply that operates O is connected to the signal line /O from the second memory device R2.
3. It is necessary to send the data through all three channels. The comparison result is input to 0PU8 via signal line /O4'ii, and it is determined whether the information sent via signal line /O1 is normal or not, as in the case of FIG. 1.

Next, the first example and the second example will be compared.

In the first embodiment, when only the first storage device 1 is disconnected, the capacitor 5 backs up only the RAM 3, but in the second embodiment, the current flows through the resistor 6 to the operational amplifier 13. If it is necessary to disconnect the two for a long time, it is necessary to use a capacitor 5 with a large capacity.

However, if there are a large number of secondary storage devices in which the system ultimately stores information, and the number of primary storage devices used for communication is small, then the comparator/O is not included in the secondary storage devices. Therefore, the configuration shown in FIG. 3 is economically advantageous.

In the first and second embodiments of the present invention described above, information is reliably transmitted without using batteries as a power source, and even if the first storage device is left alone for a long time due to loss etc. Sometimes, the contents of the first nine M used in the first storage device are automatically erased, so the contents of the third
Even if the information is passed on to someone else, there is only a small chance that the contents will be known.

(Effects of the Invention) As explained above, in the present invention, the power supply voltage stored in the large capacity capacitor is used while being compared with the reference value.
By maintaining the contents in the storage device 1, battery management is not necessary, and information can be accurately transmitted as long as the power supply voltage is normal.

Furthermore, in the case of loss or theft, the voltage of the large capacity capacitor will discharge over time, so the stored contents will be erased, which has the effect of reducing the possibility that the device will be known to a third party.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of an information transmission system according to the present invention. FIG. 2 is a block diagram showing a system for transmitting information from the information generating device to the storage device shown in FIG. FIG. 3 is a block diagram showing a second embodiment of the information transmission system according to the present invention. 1.2-...Storage device 3,9...RAM4.7-
...I/O circuit 8...CPU/O...comparator
20... Information generating device 5... Capacitor
6.11...Resistor 12...Zena diode
13...Operation amplifier 14'-19...Terminal /
O1~/O4...Signal line piece 1 figure 2 figure ■

Claims (1)

[Claims] An information transmission system configured to transmit information from an information generating device to a first storage device, and further to transmit information from the first storage device to a second storage device, the first storage device a first RAM for storing information transmitted from the information generating device; a large-capacity capacitor for supplying a power supply voltage to maintain the contents of the first RAM; a first I/O circuit for performing an input/output operation, and the second storage device includes a second I/O circuit for performing an input/output operation of the information with the first storage device. an I/O circuit, and a second RAM for storing the information input from the second I/O circuit;
and a CPU for processing the information from the second I/O circuit and the second RAM, and the first or second storage device has a power supply voltage of the capacitor as a reference voltage. An information transmission system comprising: a comparator for comparing the power supply voltage and operating the CPU only when the power supply voltage is higher than the reference voltage.