JPH01145713A - Keyboard device - Google Patents

Abstract

PURPOSE:To decrease the number of times of the processing for reading in a code by combining and outputting the code of a key corresponding to information and a code for showing the number of pieces of information which exists continuously in a buffer, when information of the same key exists continuously in the buffer and there is an output request of a host device of a system. CONSTITUTION:A keyboard control use microcomputer (KBC) 5 which is contained in a keyboard device 4 executes a scan of a key matrix 6, and checks depression and release of a key. When the depression of the key is confirmed, a code for showing the depressed key is stored temporarily in a buffer 7. Whenever a host device 1 of a system requests an output of depressed information of the key to the keyboard device by utilizing an output request signal line 3, the KBC 5 reads out successively the depressed information of the key and executes serial transfer to the host device 1 through a signal line 2. In such a way, the number of times of the processing for reading in the code can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a keyboard device controlled by a microcomputer.

BACKGROUND OF THE INVENTION In conventional keyboard devices, even when the same key information continuously exists in the buffer, each time the system's host device issues a code output request, one code stored in the buffer is Outputs the code corresponding to the key information.

Problems to be Solved by the Invention In such a conventional keyboard, when information for the same key exists continuously in the buffer, the system's host device reads such a code from the keyboard device. The same number of processing is required as the number of consecutive same keys in the buffer, so when the same code is consecutive in the buffer, such as during auto-repeat, the host device spends a lot of time processing the keyboard. and other processing will be delayed.

The present invention aims to solve these problems and reduce the number of processing times for reading code.

Means for Solving the Problems In order to solve the above problems, the present invention aims to solve the above problems.When information with the same key exists consecutively in the buffer and there is an output request from a higher-level device of the system, the key corresponding to the information is and a code representing the number of consecutive pieces of information in the buffer are combined and output.

Effects of the present invention By using the above-described means, when information of the same key exists continuously in the buffer, it is possible to reduce the number of processing times for the host device of the system to read the code of the keyboard device. You can allocate more time to processing.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a block diagram showing the overall configuration of an embodiment of the present invention. A keyboard control microcomputer (hereinafter referred to as WBC) built into the keyboard device 4
6 scans the key matrix 6 to check whether a key is pressed or released. When the press of a key is confirmed, a part of the code representing the pressed key is stored in the buffer 7. K every time the host device 1 of the system uses the output request signal line 3 to request the keyboard device to output key press information.
The BCs sequentially reads the key press information stored in the buffer 7 and serially transfers it to the host device 1 via the signal line 2. Figure 2.

FIG. 3 shows buffers 8 and 1o provided on the internal RAM of the KBC and read pointers 9 and 11 indicating addresses storing key press information to be read next. KBC is address 1000H on RAM
Key press information is stored in a buffer provided at 1ooFH. Suppose that at some point the state of the buffer is as in the second cause. At this time, when the host device of the system uses the output request signal line to request the keyboard device to output key press information, the KBC reads the contents of the address 1002H indicated by the read pointer 9 and stores the contents of the address 1002H in the buffer below. Check whether the same information as the content is consecutive. As shown in Figure 2, if it is confirmed that the same content as address 1002H continues up to address 1006H, the number of pieces of key information corresponding to this content and this information are consecutive (6 in this case).
This information is combined and output to the system's higher-level device. Then set the read pointer to 100 as shown in 11 in Figure 3.
It will be 7H. FIG. 4 shows the format of the code output to the upper level device of the system. In this embodiment, a 2-byte code is used. The first byte stores a code corresponding to the pressed key, and the second byte stores a code corresponding to the number of consecutive keys from bit 0 to pit 3. FIG. 5 shows a flowchart of an algorithm for generating code in the form of an output from information stored in a buffer. When the output request signal from the host device of the system is enabled, the KBC reads the contents of the address indicated by the read pointer. Then, the content of the read pointer is incremented and 1 is set in a counter for counting the number of output data. Next, the contents of the address indicated by the read pointer are read. If the information read last time and the information read this time are the same, the counter for the number of output data is incremented. By repeating this process until the information read previously and the information read this time are different, the number of consecutive pieces of information with the same key can be obtained. A code in the output format shown in FIG. 4 is generated based on the read information and the counted number.

Effects of the Invention As described above, according to the present invention, when information with the same key continuously exists in the buffer and there is an output request from a higher-level device of the system, the code of the key corresponding to the information is By outputting the code in combination with the code representing the number of pieces of the above information continuously present in the buffer, the keyboard processing time of the host device can be reduced and more time can be allocated to other processing. , which is extremely useful in practice.

[Brief Description of the Drawings] Figure 1 is a block diagram showing the overall configuration of a keyboard device according to an embodiment of the present invention, and Figures 2 and 3 are KBC.
Block diagram showing buffers and read pointers in the fourth
The figure is an explanatory diagram showing the format of the output code, and FIG. 6 is a flowchart of the algorithm for obtaining the code in the output format. 1... System host device, 2... Signal line, 3... Output request line, 4... Keyboard device, 6... Keyboard control microcomputer, 6... River key matrix, 7...
...Buffer, 8...Buffer, 9...
...Read pointer, 10...Buffer 1゜11
······buffer. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 4 (@1 Piece (2nd Piece) B, 7 Piece Food
Hift's engraving of drawings Part 5 (Kuno l) Engraving of drawings

Claims (1)

[Claims] It has a keyboard consisting of a key matrix and key switches arranged on the key matrix, a microcomputer that controls this keyboard, and a buffer that stores information on keys to be output to the system's host device. When outputting key information to a higher-level device of the system, the key information corresponding to the information stored in the buffer corresponds to the number of pieces of information with the same key continuously existing in the buffer. A keyboard device characterized by outputting information in combination.