Master keyboard terminal with auxiliary keyboard terminal capability
AssigneeBunker Ramo Corporation
InventorWilliam D. Baxter
Life of this patent
Estimating the term…
Abstract
A master keyboard terminal is provided to communicate with a programmable control unit. Auxiliary keyboard terminals are connected to the master terminal, and utilize a substantial portion of the logic circuitry located in the master terminal. Auxiliary terminals may be scanned by the master terminal and data entered on the auxiliary terminals are communicated, through the master terminal, to the programmable control unit.
Claims9
A system having a master keyboard terminal and an auxiliary keyboard terminal, the auxiliary terminal comprising:
- a. keyboard switch means for entering data thereon;
- b. multiplexing means having the switch means connected to a first input thereof;
- c. a second input of the multiplexing means enabled by a selection switch in the master keyboard terminal;
- d. a third input of the muliplexing means connected to the master keyboard terminal for carrying a variable count, generated by the master keyboard terminal;
- and
- e. an output of the multiplexing means for carrying a control signal upon coincidence between the data entered on the keyboard switch means and a particular count of the variable count, simultaneous with a signal appearing at the second input;
- f. the control signal transmitted to the master keyboard terminal for dumping the particular count from the master keyboard terminal to an external data processing device, corresponding to the entered data.
In a system having a master keyboard terminal and at least one auxiliary keyboard terminal, dependent upon the master terminal, the master terminal comprising:
- a. means for sequentially generating varying counts;
- b. first gating means connected at its input to outputs of the count generating means;
- c. means for manually entering data in the master keyboard terminal and means connected between the count generating means and the manual entering means for detecting coincidence between data manually entered at the master keyboard terminal and a corresponding generated count of the varying counts for producing a first control signal;
- and
- d. means for communicating the first control signal to the first gating means for dumping a particular count of the varying count from the first gating means to an external data processing device, the particular count corresponding to entered data;
- the auxiliary keyboard terminal comprising:
- e. keyboard switch means for entering data thereon;
- f. multiplexing means having the switch means connected to a first input thereof;
- g. a second input of the multiplexing means enabled by a selection switch in the master keyboard terminal;
- h. a third input of the multiplexing means connected to the count generating means for carrying the varying count;
- i. an output of the multiplexing means for carrying a second control signal upon coincidence between the data entered on the keyboard switch means and a particular count of the variable count, simultaneous with a signal appearing at the second input;
- and
- j. means for communicating the second control signal to the first gating means for dumping a particular count of the varying count from the first gating means to an external data processing device, the particular count corresponding to entered data.
Dependencies are inferred from the claim text.