Method and apparatus for keyboard control with programmable debounce and jog

A method for providing debounce and jog control for a keyboard, said method comprising:

• loading a first electronic storage register with a value indicative of a debounce period for the keyboard;
• loading a second electronic storage register with a value indicative of a jog period for the keyboard;
• scanning the keyboard for a pressed key;
• debouncing a signal indicative of the pressed key;
• providing electronic signals for key status and jog and asserting an interrupt in accordance with the indicated debounce period and the indicated jog period while the debounced signal indicates the pressed key is down;
• preventing keys of the keyboard other than the pressed key from being scanned until the debounced signal indicates that the pressed key has come up;
• and
• clocking a code for the pressed key into a register and generating an interrupt if the pressed key is active at the end of the debounce period.

An apparatus for scanning a matrix keyboard, said apparatus comprising:

• a programmable register configured to store a value indicative of a debounce time for the keyboard;
• and
• a programmable register configured to store a value indicative of a jog time for a key of the keyboard;
• and
• said apparatus configured to:
• scan the keyboard for a pressed key;
• debounce a signal indicative of the pressed key;
• provide electronic signals for key status and jog and assert an interrupt in accordance with the indicated debounce period and the indicated jog period while the debounced signal indicate that the pressed key is down;
• and
• prevent keys of the keyboard other than the pressed key from being scanned until the debounced signal indicates that the pressed key has come up.

An apparatus for scanning a matrix keyboard, said apparatus comprising:

• a first programmable register configured to store a value indicative of a debounce time for the keyboard;
• and
• a second programmable register configured to store a value indicative of a jog time for a key of the keyboard;
• and
• said apparatus configured to:
• scan the keyboard for a pressed key;
• debounce a signal indicative of the pressed key;
• provide electronic signals for key status and jog and assert an interrupt in accordance with the indicated debounce period and the indicated jog period while the debounced signal indicate that the pressed key is down;
• prevent keys of the keyboard other than the pressed key from being scanned until the debounced signal indicates that the pressed key has come up;
• and
• clock a code for the pressed key into a register and to generate an interrupt if the pressed key is active at the end of the debounce period.

A data entry apparatus comprising:

• a matrix keyboard;
• a first programmable register configured to store a value indicative of a debounce time for the keyboard;
• and
• a second programmable register configured to store a value indicative of a jog time for a key of the keyboard;
• and
• said apparatus configured to:
• scan the keyboard for a pressed key;
• debounce a signal indicative of the pressed key;
• provide electronic signals for key status and jog and assert an interrupt in accordance with the indicated debounce period and the indicated jog period while the debounced signal indicate that the pressed key is down;
• and
• prevent keys of the keyboard other than the pressed key from being scanned until the debounced signal indicates that the pressed key has come up.