| 摘要 |
A keypad device including a parallel/serial conversion device, a keypad module, and a controller coupled to the parallel/serial conversion device and the keypad module. The keys in the keypad module are arranged in parallel. After the key is triggered, an interrupt signal will be fed to the controller. On receiving the interrupt signal, the controller will feed a drive voltage to the keypad module generating a parallel signal therein. After causing the parallel/serial conversion device to read and store the parallel signal, the controller will be able to read the parallel signal serially by using the clock signals. The status of the keypad module can thereby be obtained.
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