JPH02190984A - Microcomputer device - Google Patents

Abstract

PURPOSE:To effectively utilize the number of input ports of a microcomputer by inputting a frequency signal corresponding to the state of an input switch to one input port of the microcomputer under the existing state of many input switches. CONSTITUTION:When the input switch 12 is constituted of a three-contact switching type switch e.g., a DC signal is generated from an oscillation means 13 when two contacts (a), (b) of the switch 12 are selected, and the selection of the contacts (a), (b) is inputted to the microcomputer 11 by setting up signals with 'H' and 'L' output levels. When the residual contact (c) is selected, a signal with the specific frequency is oscillated from the oscillation means 13 and the oscillated signal is inputted to an input port 111. Since signals from the switch circuit 12 with plural contacts (a), (b), (c) can be inputted to one input port 111, the number of input ports set up in the microcomputer 11 can be effectively utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a microcomputer device with an improved switch input means for inputting a plurality of mode selections using a switch to a limited number of input ports.

(2) In the above oscillation means, the switch input to the microcomputer generates a bell and low level DC state signal.
Conventionally, this is basically carried out as shown in FIG. That is, the switch SW is connected between the power supply Vdd and the ground point, and when the switch SW is in the OFF or ON state, a high label (H) or low level (L) is output to one input port of the microcomputer CPU. voltage signal is input. i.e. one 2
One input port is required in the microcomputer CPU for each switch that selects a state, and it is necessary to set a number of input ports in the microcomputer CPU corresponding to the number of input switches. For example, if there are two input switches SWI and SW2 as shown in FIG. 11, two input switches are set in the CPU of the microcomputer main body.

Also, if a three-contact switch is set, there will be three input states, so it is not possible to simply import inputs that identify the three states from one input port as described above. Have difficulty.

As a countermeasure for such a case, for example, Japanese Patent Application Laid-open No. 63
For example, as disclosed in Japanese Patent No. 115416, analog input data from a multi-contact switch can be
Measures are being considered to reduce the number of input ports of a multi-input switch by converting the signal into a digital signal and inputting the signal to an input port specified as a digital switch. However, converting each contact point of the switch section into unique digital data unnecessarily complicates the input circuit section.

[Problems to be Solved by the Invention] This invention has been made in view of the above points, and is intended to make it possible to effectively utilize the number of input ports set in a microcomputer. The present invention aims to provide a microcomputer device that can input a signal from a switch that makes a plurality of selection contacts high to a boat.

[Means for solving the problem] In the microcomputer device according to the present invention,
For example, set the oscillation means constituting an OP amplifier so that it is connected to the input port of the microcomputer,
The oscillation frequency of the oscillation means is variably set in accordance with the selection setting means of the input switch.

[Function] In the microcomputer device configured as described above, when the input switch is configured, for example, by a three-contact changeover type switch, when two contacts of this switch are selected, the oscillation means By generating a DC signal and setting its output level to H and L level signals as in the conventional case, the selection of this contact can be input to the microcomputer. Then, when the remaining one contact is selected, the oscillation means oscillates a signal of the specified frequency, and this oscillation signal is input to the input port. in this case,
The oscillation frequency can be set in accordance with the selected contact, so that signals from a plurality of contact circuits can be input to one input port.

[Embodiments of the invention] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows its configuration, which has an input switch 12 having three selection contacts a, b, and c for one input port 111 of a microcomputer 11. In this case, the above a-c are “L” and “OFF” respectively.
Each corresponds to "L".

The output terminal section from this input switch 12 is an oscillation circuit 1 including an OP amplifier I3 and resistors R1 to R4.
Further, a capacitor C is connected to the output terminal of the switch 12.

In this microcomputer device, the output state of the oscillation circuit 13 is changed corresponding to the three states of H'"OFF" and "L" of the input switch 12, and the output signal from the oscillation circuit 13 is It is co-supplied to one input port Ill of computer 11.

In this device, the potential at point A is set in accordance with the setting state of the input switch 12, and when the switch 12 is in the "H" state connected to the C contact, the above point A is connected to the power supply. When the voltage is set to Vdd and the switch 12 is connected to the C contact in the "L" state, the point A is set to the ground potential.The point A is connected to the (-) terminal of the OP amplifier, and this point A is grounded via a capacitor C, and is connected to the output side of the OP amplifier via a resistor R4.

In addition, the (+) side terminal of this OP amplifier is connected to the power supply Vdd.
The potential at point B, which is divided by resistors R1 and R2, is 0 (supplied).

To explain the operating principle of such an oscillation circuit 13, the input at the above point B is equal to the voltage set by the resistors R1 and R2.
The voltages VL and ■H are set by the hysteresis characteristic with feedback by the resistor R3,
The potential at point A oscillates by repeatedly charging and discharging capacitor C via resistor R4. Switch 12 at this time
The states of the potentials at the points A and B corresponding to the "L", "OFF" and "Ho" states are as shown in FIG. 2, and the corresponding states of the input port lft of the microcomputer 11 are also as shown in FIG. , are shown simultaneously in this figure.

FIG. 3 explains a mode in which each of the above states is determined at the input port 111. When the input from the switch 12 is in the "L" and "H" states, the input port Il
The potential of l is set to "H" and L, respectively. Then, when the output of switch 12 is in the "OFF" state, an oscillation signal with period TI is supplied to input port I. This oscillation period Tl is set corresponding to the boat sampling period.

FIG. 4 shows the relationship between the oscillation signal and boat sampling, in which the boat sampling cycle TS is set to be "Ts<Tl" with respect to the oscillation signal cycle T1, and the cycle Ts I try to check the boats at For example, in this figure, "Tl'14Ts"
Ts is set in the relationship, and input port 111
is checked four times, and if all of them are "H", it is determined that the input from switch 12 is "H", and conversely, if all of them are "H", switch 12 is set to "L". If the input port 111 is in a state other than the above, it is determined that the input of the boat ill is "oscillation" and the setting state of the switch I2 is "OFF".
The microcomputer IT can now execute processing according to the input state of the switch 12.

The above-mentioned determination of the three states of the input at the input port lll is executed by the processing shown in FIGS. 5 to 7. First, as shown in FIG. 5, in the main process, initial settings are performed in step lot.

In step 101 of this initial setting, as shown in FIG.
UNTL is set to "0", and furthermore, in step 202, a counter C0UNTH that counts the "H" state of the input port 111 in accordance with the sampling period is set to "0". Further, in step 203, the sampling number N of the input port 111 is set to "0", and in step 204, the input port 111 that stores the determination results of a certain period (four times) is set to "0".
The state register RP of No. 1 is set to "O", and the processing of that pond is set to the initial state at step 205.

Once the initial settings have been made in this way, the process proceeds to the next step 102, where the timer is observed to determine whether or not it is the timing of the cycle Ts, and when it is determined that the timing is TS, the process proceeds to step 103. , reads the input port 111, and determines the state of the input port 111 in step 104. Then, the "L", "OFF", and "H" states of the switch 12 are determined in accordance with the determination result, and in any of steps 105 to 107, one of the processes 1 to 3 is executed by the microcomputer 12. will now be executed.

FIG. 7 explains the processing in the step of determining the boat status. First, in step 301, the boat is read, and in step 302, it is determined whether the status of the input port 11 is at H level or L level. Determine. Then, when it is determined that the H level is high, the process proceeds to step 303, where COUNT H is counted by "+1°", and when it is determined that the L level is low, the count + is "counted" at step 304.
+1" is counted. Thereafter, the process proceeds to step 305, where the sampling number N of the input boat 1ll is incremented by "+1", and in the next step 306, it is determined whether the value of N has become "4°. If the value of N has not reached "4" yet, this process ends and the sampling count number reaches "4".
”, proceed to step 307 and change the above N to “
Set it to 0''.

In step 308, the state of C0UNT L is determined, and if it is confirmed that this C0UNT L is counting "4", the process proceeds to step 309 and the input port lit
The status register RP of is set to "2". That is, in FIG. 5, step 107 is selected by step 104.

Further, if it is determined in step 308 that C0UNT L is not "4", the process advances to step 310, and C0U
This is to judge whether or not NT H is 4゛, and if it is judged that the count value is "4", step 31
1, and set the status register RP of the input boat 111 to “
0". This corresponds to step 105 in FIG. and step 312
Then, the status register RP is set to "1". This is the fifth
This corresponds to proceeding to step 10G in the figure.

That is, the three states of the input switch 12 are determined at the input port 111 of the microcomputer 11. For example, when the input switch 12 is used to change the display of a vehicle totalizer, one changeover switch can change the display of TripA, TripB, and odometer.

In the device configured as described above, if the hysteresis potential is varied with respect to point B using a plurality of resistors and switches, the oscillation frequency of the oscillation circuit 13 can be changed at the same time, and the oscillation frequency of the oscillation circuit 13 can be changed at the same time. A sampling frequency that allows the oscillation frequency to be measured allows the boat to be checked, thereby allowing more switch inputs to be input from one input port.

FIG. 8 shows another embodiment, in which a plurality of switching type switches 121 to 12 are connected to point B.
4 is connected, and the power supply Vdd or ground point is selectively connected, and the potential corresponding to the setting state of each switch 121 to 124 is set to B by the resistor circuit.
It is set to a point.

In the above embodiment, the inputs from the plurality of changeover switches are
Although the state in which the power is supplied to one input port 111 of the microcomputer 11 is shown, if a plurality of on/off switches are used, the configuration may be as shown in FIG. 9.

That is, a plurality of switches 125 to 1 each having one end grounded
27 are connected to point B via resistors R5 to R7, each having a different value. Therefore, if one of switches 125-127 is connected,
The potential corresponding to the switch is set at point B, and the oscillation circuit 13 oscillates a signal with a frequency corresponding to the potential at point B, which is then supplied to the input port of the microcomputer 11. . Then, the microcomputer 11 determines the switch input state based on the input frequency.

[Effects of the Invention] As described above, in the microcomputer device according to the present invention, in a state where a large number of input switches exist, for one input port of the microcomputer, the state corresponding to the state of the input switch is adjusted. Frequency signals can now be taken in, effectively resolving the shortage of input ports in microcomputers. Therefore, the number of input switches for controlling the microcomputer can be easily increased, and the manner in which the microcomputer is used can be further expanded, and its range of applications can be easily expanded.

[Brief explanation of the drawing]

FIG. 1 is a circuit configuration diagram illustrating a microcomputer device according to an embodiment of the present invention, FIG. 2 is a diagram illustrating the input state to the input port of the microcomputer in the device, and FIGS. 3 and 4 are 5 to 7 are flowcharts illustrating the input processing mode of the above device, and FIGS. FIGS. 10 and 11 are circuit configuration diagrams showing other embodiments of the invention, respectively, which are configuration diagrams illustrating conventional microcomputer devices. 11... Microcomputer, 12... Input switch, 13... Oscillation circuit. Applicant's Representative Patent Attorney Takehiko Suzue Figure 3 Figure 4 @6 Figure 2 Figure 5 Figure 8 Figure

Claims (3)

[Claims] (1) An input switch means for selecting and setting at least three switching modes, and an oscillation means for setting an oscillation frequency corresponding to one mode selected by the switch means. The signal generated by the oscillation means is supplied to one input port of the microcomputer main body, and the microcomputer main body determines the mode set by the switch means in accordance with the input signal frequency. A microcomputer device featuring: (2) The microcomputer device according to claim 1, wherein said oscillation means generates high-level and low-level DC state signals corresponding to at least two setting modes of said switch means. (3) The switch means includes a resistance circuit whose resistance value is changed and set in accordance with the selected setting state of the switching mode, and the oscillation frequency of the oscillation means corresponds to the resistance value of the resistance circuit. Claim 1 set out
microcomputer equipment.