发明名称 Shared use of keyboard and memory lines
摘要 The present invention describes a method and apparatus for interconnecting keyboard lines and memory lines to the same pins of a microprocessor or calculator chip. Resistors are placed in series with each keyboard line before interconnection to the memory lines and microprocessor pins to prevent disruption or degradation of the memory signal in the event a key on keyboard is depressed during a memory operation cycle. Means are provided to prevent memory operations during keyboard scan routines and means are provided to prevent keyboard scan routines from operating during memory operation cycles.
申请公布号 US5065356(A) 申请公布日期 1991.11.12
申请号 US19880285991 申请日期 1988.12.19
申请人 HEWLETT-PACKARD COMPANY 发明人 PUCKETTE, ROBERT B. E.
分类号 G06F13/42 主分类号 G06F13/42
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