| 摘要 |
A keyboard, having a plurality of actuatable key switches and an encoder responsive to actuation of each of the key switches for generating a character associated with each actuated key switch, includes a cycle time controller for making all of the characters potentially cycleable. The keyboard encoder, in addition to generating a character, will also generate a KEY SWITCH ACTUATED signal upon actuation of any one of the key switches and until the key switch is deactuated. The cycle timer controller responds to the generation of the KEY SWITCH ACTUATED signal and generates, after the lapse of a predetermined period of time from when the key switch was initially actuated and while the KEY SWITCH ACTUATED signal is still being generated, a CYCLE CHARACTER signal which may be used by a programmable terminal to cause cycling of the character generated by the decoder upon actuation of the key switch. If actuation of a first key switch is followed by actuation of a second key switch, then upon occurrence of the latter the cycle timer controller will be reinitialized and generate the CYCLE CHARACTER signal after the lapse of the predetermined time period from when the second key switch was actuated and while it remains actuated.
|
