JPS6237406B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to a keyboard applied to a device in which a processing unit CPU performs processing corresponding to the press of a key based on key information stored in a memory. Regarding control circuits.

(2) Background of the Technology Usually, keyboards are provided with continuous keys such as typer-machine keys, in which pressing the same key remains valid for the CPU as long as the key is pressed. Such continuous keys are often used when scrolling up and down the display.

(3) Prior Art and Problems FIG. 2 is a diagram showing a display device using a conventional keyboard control circuit.

Conventionally, in this type of device, when the key 8 on the keyboard is pressed, as shown in FIG.
When the counter 10 scans, the key matrix 11 outputs a press signal PS, which sets the flip-flop 4 and notifies the CPU 3 that the key has been pressed. The CPU 3 immediately returns the address ADS of the counter 10 stored in the register 6 at that time, that is, the address of the pressed key 8.
The ADS is read and the process corresponding to the press of the key with the corresponding address ADS is performed. but,
It is difficult to make the processing of the CPU 3 temporally correspond to the press of the key 8 because the information processing capacity of the CPU 3 and the processing time for each key press are not constant.
is temporarily stored in the memory 5 as key information KIF, and the CPU 3 performs corresponding processing based on the key information KIF in the memory 5. However, when consecutive keys are pressed, the CPU 3 detects when one consecutive key is pressed (which key on the keyboard is pressed is captured at regular intervals by the counter 10, so if a key is pressed continuously) Even in this state, the same address ADS is written to the memory 5 as key information KIF at regular intervals, assuming that the key is pressed at regular intervals.
It is stored in the memory 5 as key information KIF. If you keep pressing consecutive keys that involve complicated processing such as scrolling up and down, the processing of the CPU 3 will not be able to keep up with the speed at which the key information KIF in the memory 5 is taken in, and the key information of the consecutive keys will not be stored in the memory 5.
KIF keeps accumulating unprocessed. For example, when an operator instructs the CPU 3 to scroll up or down using consecutive keys, even if the screen on the display 2 is scrolled up or down to the appropriate position and the operator stops pressing the consecutive keys, the memory 5 for
This means that the key information KIF of the consecutive keys that has not been processed by the CPU 3 remains, and even after the key is no longer pressed, the CPU 3 continues to scroll up and down, and the key information KIF is not processed by the operator.
The processing of the CPU 3 and, therefore, the display on the display 2 no longer corresponds to each other, resulting in a display that is different from the operator's intention, resulting in poor operability.

(4) Purpose of the Invention In order to solve the above-mentioned drawbacks, the present invention notifies the CPU of the release of the pressed state of successive keys, and causes the CPU to perform processing corresponding to the successive keys pressed. It is an object of the present invention to provide a keyboard control circuit that can be immediately stopped upon release.

(5) Structure of the Invention That is, the present invention provides a key map that records at least the pressed states of consecutive keys, and changes in the pressed states of the keys recorded in the key map based on the contents of the key map and the pressed signals from the key matrix.
It is configured with a comparison circuit that notifies the CPU.

(6) Embodiments of the Invention The present invention will be specifically described below based on embodiments shown in the drawings.

FIG. 1 is a circuit diagram showing an example of a display device to which an embodiment of the keyboard control circuit according to the present invention is applied.

The display device 9, as shown in FIG.
The CPU 3 is connected to a memory 5, a display 2, a register 6 constituting the keyboard control circuit 1 according to the present invention, and a comparison circuit 7.
A counter 10 is connected to the register 6, and to the counter 10 are connected a key matrix 11 and a key map 12, which are provided opposite to the key 8 on the keyboard and detect when the key 8 is pressed. is the key map 12 and comparison circuit 7
is connected.

Since the present invention has the above-described configuration, when a consecutive key among the keys 8 on the keyboard is pressed, the contacts corresponding to the pressed consecutive keys on the key matrix 11 become conductive. On the other hand, the counter 10 updates the address ADS and sequentially updates the matrix 11.
and the address being scanned.
Output ADS to register 6 and key map 12. The key map 12 has a bit corresponding to each consecutive key on the keyboard, and each bit indicates the pressed state of each consecutive key, that is, "1" when the key is pressed, and "1" when the key is not pressed. 0" is written. Therefore, when the address ADS of a consecutive key is output from the counter 10 to the map 12, the bit contents corresponding to the address ADS are read out to the comparator circuit 7. On the other hand, the pressed state of a continuous key is determined from the matrix 11 to the map 12 as a pressed signal PS (the signal PS is "1" when the key is pressed, and "0" when it is not pressed) when the matrix 11 is scanned based on the address ADS. and comparison circuit 7
After reading the bit contents from the address ADS from the counter 10 to the comparison circuit 7, the map 12 calculates the pressed state of the consecutive keys at the address ADS based on the press signal PS and the corresponding key. Rewrite by updating the bit contents. The comparison circuit 7 compares the bit contents read from the map 12, that is, the previous counter 10.
Based on the pressed state of the continuous key during the scan and the contents of the pressed signal PS during the current scan, check whether the continuous key is also pressed during the current scan.
It detects whether the pressed state has already been released or whether the pressed state has newly entered, and notifies the CPU 3 as a signal IS. This signal IS is a signal that can contain state information of the detection result, and the processing device may receive the state information at the same time as this signal, or read the state information based on this signal IS. You may also receive That is, when the bit content of map 12 is "0" and the signal PS is "1", it means that the key has been pressed since the current scan, and the CPU 3 is notified of this by the signal IS, and the CPU 3 writes the memory 5. , the contents of register 6, that is, the address of the newly pressed consecutive key.
Store ADS as key information KIF. Furthermore, if the bit content is "1" and the signal PS is also "1", the key continues to be pressed during the previous and current scans, and the signal IS notifies the CPU 3 of this fact, and the CPU 3 stores the memory 5. , store the same address ADS as last time. Further, if the bit content is "1" and the signal PS is "0", the pressed state of the key is released from the current scan, and the CPU 3 is notified of this by the signal IS. In this case, if unprocessed key information KIF regarding the relevant consecutive key is stored in the memory 5, the CPU 3 discards such information KIF and cancels the previously pressed state. Immediately interrupts processing corresponding to consecutive keys. In addition, if the bit content and signal PS are both "0",
Since the continuous key was not pressed during both the previous and current scans, the comparison circuit 7 does not send any notification to the CPU 3.

In addition, although the above-mentioned embodiment described the case where the key map 12 that records the pressed state of the key 8 is continued only for consecutive keys, the key map 12 may also be provided for other ordinary keys as long as it is provided for at least the consecutive keys. is free, and it is naturally possible to detect the pressed states of all keys 8 on the keyboard using the map 12 or the like.

(7) Effects of the Invention As explained above, according to the present invention, there is a key map 12 that records at least the press state of successive keys, and the press of successive keys is determined based on the contents of the key map 12 and the press signal PS from the key matrix 11. Since the comparison circuit 7 is provided to notify the CPU 3 of changes in the state, it is possible to notify the CPU 3 of changes in the pressed state of consecutive keys, especially the release of the pressed state. If the operator stops pressing the key when instructed, the key information KIF corresponding to the scroll up/down that has not been processed by the CPU 3 in the memory 5 will be immediately discarded and subsequent processing will be aborted. Key operations and the display on the display 2 appear to correspond, and operability can be greatly improved.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an example of a display device to which an embodiment of the keyboard control circuit according to the present invention is applied, and FIG. 2 is a diagram showing a display device using a conventional keyboard control circuit. 1...Keyboard control circuit, 3...CPU, 5
...Memory, 7...Comparison circuit, 8...Key, 9...
...Display device, 11...Key matrix, 12...
Key map, PS...press signal, KIF...key information, ADS...address.

Claims (1)

[Claims] 1. A processing device, a memory connected to the processing device, a continuous key, and a key matrix, which detects a pressed key via the key matrix, and stores the address of the key in the memory. The processing device sequentially reads out the key information in the memory and performs processing corresponding to the pressed key, at least a key map that records the pressed state of consecutive keys, and a key address that is updated sequentially. By comparing the content of the key map corresponding to the key address with the signal content from the key matrix corresponding to the same key address, it can be determined that the key has been newly pressed, that the key continues to be pressed, and that the key has been released. and a comparison circuit that detects that the key has been released and notifies the processing device accordingly, and the processing device stores the unused data in the memory when the comparison circuit notifies that the key has been released. A keyboard control method characterized by not performing processing corresponding to key information stored in a processing state.