| 摘要 |
An electronic keyboard is disclosed in which the keyboard matrix is scanned by an integrated circuit scanner which incorporates a programmable repeat rate and repeat delay rate counter. The repeat interval of a key is achieved by setting the repeat counter to a predetermined count value so that this repeat interval is obtained when a repeatable key has been depressed. The repeat delay rate interval is delayed by a count value that is set in the counter so that the repeat delay interval may be shortened when a repeatable key is held down for continued repeating of the code signal. In the keyboard an eight bit counter is utilized in which all eight bits can be used for the delay rate, but in all cases the four least significant bits are used for the repeat rate. Both the repeat rate and the delay rate are externally programmable during the same programming period, under the control of external processing equipment to which the keyboard is connected. External programming of the repeat rate and the repeat delay rate counter allows the keyboard to be produced at a reduced cost over microcomputer implemented keyboards.
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