JPH0310312A - General interface circuit between key scan input system adopting device and digital output device - Google Patents

Abstract

PURPOSE:To couple a key scan input system adopting device, where digital input is not taken into consideration, and a digital output device without remodeling an input device by connecting electronic analog switches to key scan switches respectively in parallel. CONSTITUTION:An analog switch ASWij 2 is connected in parallel to a switch SWij 1 connected to the key scan signal line in the j-th column and the i-th row. A control line of this analog switch 2 is connected to the K-th signal line of a digital data N-bit decoder 3. Consequently, when the digital output has the binary value K and make of the analog switch ASWij 2 has another value, remake is possible. Thus, a general interface circuit is obtained which couples the key scan input system adopting device where digital input is not taken into consideration and the digital output device without remodeling the input device.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a general-purpose interface circuit for enabling a digital output device such as a computer to control a device that employs a key scan input method. .

One application field is the automatic control of devices that use the key scan input method, such as VTR remote controls and calculators, which were created on the premise that humans would control them by directly pressing a switch button, using a personal computer. There are cases where this is the case.

The characteristics of these devices are that the data speed is relatively slow, but they have many selectors to input, ie, many input switches. For such inputs, there are great advantages in adopting the key scan input method, and many products use this key scan input method. In general, there are N columns and M rows of human power lines for key scanning.
Maximum NM switch inputs are possible.

On the other hand, digital devices such as computers use digital data that is easy for machines to send and receive data. In this case, with N data signal lines, a maximum of 2 N
Multiplication data can be exchanged at one time. The present invention absorbs these differences in data exchange and realizes a circuit that performs key scan type data input using a digital output.

[Prior art] Even if the device uses the key scan input method,
In many cases, a digital signal is used inside the device, and in such cases, there is a method of achieving the purpose by directly connecting a digital output signal for control to a digital signal path inside the input device. However, in order to make this kind of connection possible, it is necessary to modify the device itself that uses the key scan input method, or to create an input terminal for digital manual input on the input device from the beginning. .

Although this is necessary, there is a feature that causes arbitrariness in the correspondence between the key scan row/column address and the digital data value.

In the second claim, by adding a storage device to the analog switch circuit of the first claim, a circuit that simultaneously makes and remakes a plurality of key scan switches is realized using an analog switch. . As a result, for example, on a VTR remote control, control corresponding to two switch operations at the same time, such as pressing the Pl button while pressing the rREC button and J pressing the AV button, becomes possible.

Generally, this circuit makes it possible to control the operation of any key scan switch using digital signals.

In claim 3, electronic analog switches are arranged independently in the column and row address of the key scan input, and these analog switches are selected by digital output data to achieve the object. In this case, it is possible to control the operation of one arbitrary key scan switch using a digital signal. [Problems to be solved by the invention] The object of the present invention is to provide a device using a key scan input method that does not take into account digital human power. and a digital output device without modifying the input device.

[Means for Solving the Problems] In order to achieve the two-legged objective, the circuit of the present invention arranges electronic analog switches in parallel with the key scan input switch, and uses digital signals to switch these electronic analog switches. Purposes are achieved by making and remaking. As a result, even when this circuit is added to a key scan input device, the original J switch button for key scan is effective, and the input using this button is not restricted in any way.

In claim 1, the object is achieved by connecting an electronic analog switch to each key scanning switch in parallel. In this case, the number of electronic analog switches is the same as the number of key scanning switches. Further, two sets of N-to-1 type changeover switches for column/row selection and selection are sufficient as analog switches.

In claim 4, by adding a memory circuit to the circuit in claim 3 and connecting a plurality of them (L groups) in parallel, the operation of any plurality of switches (maximum number) can be controlled by digital signals. It becomes possible to control. For example, VTR
On the remote control, while pressing the rREC button, press PLA.
The control that corresponds to two switch operations at the same time, such as "Press the Y button," is defined in claim 4 as having a degree of parallelism of 2.
This is possible by setting ``-''.

[Example 1] FIG. 1 shows the configuration of an apparatus implementing claim 1 of the present invention. key scan signal line column,
Switch 5Wij connected to jth, row 1st
Connect the analog switch ASWij in parallel with . The control line of this analog switch is connected to the first signal bus line of the digital data N-bit decoder. This ensures that when the digital output is a binary value, the analog switch ASWi
If the make of j is another value, the remake can be realized.

Furthermore, there is a degree of freedom in associating digital data values with key scan row/column addresses (i, j), making it possible to create a correspondence that is convenient for both the digital signal output device and the key scan input device. can.

FIG. 2 shows the configuration of an apparatus implementing claim 2 of the present invention. In this figure, the analog switch ASWij of FIG. 1 is connected between the output AK of the N-bit decoder via a storage circuit. This ensures that when the digital output is a binary value, the analog switch ASWi
, i can be remade when the value K is specified again after going through other values. This makes it possible to control the make/remake of another analog switch while making the analog switch ASWij.

Note that the correspondence between the digital data value and the key scan row/column address (i, j) is freely connected. By setting the value k in the digital recording control data, it becomes possible to perform make/remake control of an analog switch equivalent to the circuit shown in FIG. Therefore, it is possible to control the make/remake of another analog switch "k" while keeping the analog switch "k" made.The analog switches shown in FIG. 3 of the L circuit are mounted in parallel. In this case, maximum number of simultaneous make-ups can be realized.

[Effects of the Invention] As detailed above, according to the method of the present invention, a device that adopts a key scan input method that does not take digital input into account and a digital output device can be combined without modifying the human-powered device. It becomes possible to obtain a general-purpose interface circuit.

[Brief explanation of the drawing]

FIG. 1 is the same as the first claim of the present invention, FIG. 2 is the second claim of the present invention, and FIG. 3 is the same as the first claim of the present invention. FIG. 3 shows the configuration of an apparatus implementing claim 3 of the present invention. In this figure, the key scan column signal line is connected to an electronic analog changeover switch for column selection, and the digital column selection data KJ
This shows that the signal line in the column is selected. Similarly, it is assumed that the i-th row signal line of the key scan is selected by the digital row selection data Ki. This creates the same state as the make of the switch 5WiJ connected to the 5th column and i-th row of the key scan signal line in the entire circuit diagram. By changing the digital data, it is possible to remake SW]j. All keys can be remade by setting values that do not correspond to the signal lines in either rows or columns. FIG. 4 shows the configuration of an apparatus implementing claim 4 of the present invention. In this figure, a plurality of circuits in which a memory circuit is added to the circuit in FIG. 1 in Figures 1 and 2 is column 5 of the key scan signal line.
2 is the analog switch ASWi connected in parallel to the switch 5Wjj connected to the i-th row and the switch 5Wjj.
j, 3 represents a digital data N-] decoder, and 4 represents a storage circuit. In FIG. 4, 1 represents an electronic analog changeover switch, and 2 represents a memory circuit. digital storage control data

Claims (1)

[Claims] 1. A circuit that selects a column and row address of a key scan input using digital output data, and performs make/remake of switches in conjunction with the selected column and row address using an analog switch. 2. A circuit that simultaneously makes and remakes a plurality of key scan switches by adding a storage device to the analog switch circuit according to claim 1. 3. A circuit that independently selects the column and row address of the key scan input using digital output data, and performs make/remake of the switch in conjunction with the selection using a multilayer analog switch. 4. A circuit in which a plurality of the circuits according to claim 3 with a memory circuit added are prepared in parallel, and a multilayer analog switch is used to simultaneously make and remake a plurality of key scan switches.