Keyboard and keyboard checking method

Abstract

The invention relates to a keyboard and a keyboard checking method. The keyboard comprises a key-press matrix and is characterized by also comprising a column divider resistance chain, a row divider resistance chain and a voltage checking circuit, wherein the column divider resistance chain is connected in series between column interfaces of the key-press matrix, the row divider resistance chain is connected in series between row interfaces of the key-press matrix, and the voltage checking circuit is used for checking partial pressure potential. After a key is triggered, the voltage checking circuit compares the checked row partial pressure potential and the checked row reference potential of the triggered key to define a column value of the triggered key and compares the checked column partial pressure potential and the checked column reference potential of the triggered key to define a row value of the triggered key. The method comprises the steps: checking the row partial pressure potential and the column partial pressure potential of the triggered key; and respectively comparing the row and column partial pressure potential and the row and column reference potential of the triggered key to define the column value and the row value of the triggered key. The keyboard and the keyboard checking method are implemented, and the keyboard is only provided with four pins.

Description

technical field [0001] The invention relates to a signal input device, more specifically, to a keyboard and a keyboard detection method. Background technique [0002] The traditional button matrix has the basic structure of a quadrangular matrix, and its circuit diagram is as follows: Figure 1 As shown, this is a 4×7 button matrix circuit, which has 7 column pins of R1-R7 and 4 row pins of C1-C4, a total of 11 pins. In the normal state, scan for the column first, first set the column interface to a high potential with high impedance, and set the row interface to a low potential with low impedance. If any button on R1-R7 is pressed, the The low potential will be detected, and then the system will read the data into and save it, then scan the row, set the column interface to a low potential with low impedance, and then set the row interface to a high potential with high impedance. If any button on C1-C4 is pressed, the low potential will be detected on the line interface, an...

AI Technical Summary

Problems solved by technology

Moreover, in order to support more buttons in the future, more pins need to be reserved on the control circuit board, which greatly reduces the versatility and processing performance.

Furthermore, because this circuit does not have the ability to detect pressing, it needs a special logic circuit to realize pressing detection, so the system must scan continuously, resulting in unnecessary power consumption.

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