JPH02245814A - Data setting circuit - Google Patents

Abstract

PURPOSE:To reduce a current consumption by using toggle switches as the switch for setting data. CONSTITUTION:Plural toggle switches SW1-SWn in a setting switch part S are connected between a power source Vdd and a ground. Movable contact points a1-an in respective toggle switches are connected to a setting state monitoring part MPU. First fixed contact points b1-bn are connected to the power source Vdd, and second fixed contact points c1-cn are grounded. When respective toggle switches are set in a first or a second state by a manual operation, digital information can be set. The information is detected in the setting state monitoring part MPU. A direct current is prevented from flowing from the power source Vdd to the ground even when the toggle switches are in the first or the second state. Thus, a data setting circuit with the less current consumption can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data setting circuit, and more particularly to a data setting circuit including a setting switch section for setting data such as a self-address.

[Prior Art and Problems Therein] There are various cases in which signal processing is performed based on data set according to the open/closed state of a switch section.

For example, in disaster prevention equipment such as a fire alarm system in which a fire receiver is connected to multiple fire detectors or terminal devices such as repeaters, each fire detector or repeater is on the side, in digital form depending on the open/closed state of the switch corresponding to "0" or "1".
For example, data such as an address is set. Each of the digital data r□, , set in the switch section
rl is detected by monitoring the current or voltage that flows depending on whether the switch is open or closed.

Examples of conventional data setting circuits of this type are shown in FIGS. 2(a) and 2(b). In the case of FIG. 2(a), each Switches sw and '˜SWn' connected in series with the resistor R are provided. The potentials at the connection points between the switches sw, ' to SWn' and the corresponding resistors R vary depending on the open/closed state of each switch, and the microprocessor MPU monitors these potentials to know the setting data.

In the circuit configuration of FIG. 2(a), the switch SW
Considering the state in which 1°~SWn' are all closed,
The current I represented by the formula % formula % flows steadily, making it difficult to reduce current consumption.

On the other hand, in the case of FIG. 2(b), the switches sw, "~SW
A transistor Q is provided between each series connection body of the resistor R and the series connection body and the power supply Vdd, and the transistor Q is turned on only when monitoring the open/closed state of the switch to apply the power supply Vcld to the series connection body. Therefore, the current consumption is calculated using the formula (%) (%) Here, t is the time during which the power is applied to monitor the open/closed state of the switch, and compared to the case of Fig. 2(a), the current consumption is Although it is possible to reduce the current consumption to a certain degree, it is possible to reduce the current consumption to a certain extent, but
Not only were hard components needed to turn it off (in this case, the microprocessor MPU board, resistor, transistor), but a program was needed to control it.

[Means for Solving the Problem] Therefore, an object of the present invention is to provide a simple circuit with low current consumption, which is suitable for disaster prevention equipment such as fire alarm equipment that requires monitoring using a built-in power supply during a power outage. This is an attempt to realize a data setting circuit of the configuration.

Therefore, according to the present invention, there is provided a setting switch section including a plurality of switches connected between a power source and ground and settable to the first or second state, and monitoring the setting state of each switch in the setting switch section. a setting state monitoring section that detects setting data by and a toggle switch connected to ground.

[Operation] A toggle switch is used as each switch in the setting switch section, a movable contact of the toggle switch is connected to a setting state monitoring section, and a first and second fixed contact of the toggle switch are connected to a power source and ground, respectively. I did it like this,
There is no direct current flow from the power supply to the ground, and a data setting circuit with low current consumption can be realized with a simple circuit configuration.

[Example] An example of the present invention will be described below with reference to FIG. In the data setting circuit of FIG. 1, a plurality of toggle switches SW1 of the setting switch section S are connected between the power supply Vdd and the ground.
~ SWn are connected, and the movable contacts a1 to al of each toggle switch are connected to a setting status monitoring unit (in this embodiment, it is a microprocessor MPU).
The fixed contacts S, ~bn are connected to the power supply Vdd,
The second fixed contacts c1 to ell are grounded.

With the above configuration, each of the n toggle switches assumes the first state when the movable contact is turned over to the first fixed contact, applies the power supply voltage to the setting state monitoring section, and also switches the movable contact to the first fixed contact. When the second fixed contact is brought down, the second state is assumed and the ground potential is applied to the setting state monitoring section. Therefore, by manually setting each toggle switch to the first or second state, the first state can be changed to, for example, the digital "1" state.
", the second state is represented by a digital "O", digital information such as an address can be set, and the information can be detected by the setting state monitoring unit, ie, the microprocessor MPU. In this case, no current flows directly from the power supply Vdd to the ground in either the first or second state of the toggle switch.

Here, the data setting circuits of FIGS. 2(a) and 2(b) and that of FIG. 1 will be compared in terms of current consumption.

Vdd = 5 (V) R = 5 (KΩ) t = 1 (seconds) t: Time to monitor the open/close states of the switches SW, assuming that the number of switches SW is 8 and all switches SW are in the closed state Then, in the case of Figure 2 (a), I+ = 5V15 and Ω x 8 = 8mA
(Always) In the case of Figure 2(b), if Tr is the transistor base current, I2 = (5V15Ω)X8+Trζ IImA×
8 - 8 mA (but only for 1 millisecond) In the case of Figure 1, only the leakage current flows, so I s '' = (0 + * A) x 8 ζ0, and the current consumption in Figure 1 is It can be seen that it is even better in terms of reducing the amount of water.

[Effects of the Invention] As described above, according to the present invention, since a toggle switch is used as a switch for setting data, there is no connection from the power supply to the ground in either the first state or the second state of the toggle switch. There is no direct current flow, and therefore a data setting circuit with low current consumption can be realized with a simple circuit configuration.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing a data setting circuit according to an embodiment of the present invention, and FIGS. 2(a) and 2(b) are circuit diagrams showing conventional data setting circuits. Processor (setting state monitoring unit), S is a setting switch unit, SWl to SWn are toggle switches, a, to &n are movable contacts, b, to bn are first fixed contacts, c1 to cn are second fixed contacts, Vdd is a power supply. +Vdd Figure 1 Figure 2 (b)

Claims (1)

[Claims] A setting switch section including a plurality of switches connected between a power supply and ground and settable to a first or second state, and monitoring the setting state of each switch in the setting switch section. and a setting state monitoring section that detects setting data, wherein each of the switches has a movable contact connected to the setting state monitoring section, and a first and second fixed contact connected to a power supply and a ground, respectively. A data setting circuit characterized in that it is a connected toggle switch.